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Front Cover | |
Title Page | |
Table of Contents | |
Credits | |
Report of the director | |
Report of the administrative... | |
Agricultural economics | |
Agricultural engineering | |
Agronomy | |
Animal science | |
Botany | |
Dairy science | |
Editorial | |
Entomology | |
Food technology and nutrition | |
Forestry | |
Fruit crops | |
Library | |
Ornamental horticulture | |
Plant pathology | |
Plant science station | |
Poultry science | |
Soils | |
Statistical section | |
Vegetable crops | |
Veterinary science department | |
Central Florida station | |
Citrus station | |
Everglades station | |
Indian River field laboratory | |
Plantation field laboratory | |
Gulf Coast station | |
North Florida station | |
Range cattle station | |
Sub-tropical experiment statio... | |
Suwannee Valley station | |
West central Florida station | |
West Florida station | |
Federal-state frost warning... | |
Potato investigations laborato... | |
Strawberry investigations... | |
Watermelon and grape investigations... | |
Index |
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Front Cover
Front Cover Title Page Page 1 Table of Contents Page 2 Credits Page 3 Page 4 Page 5 Page 6 Page 7 Page 8 Page 9 Page 10 Page 11 Page 12 Report of the director Page 13 Page 14 Page 15 Page 16 Page 17 Page 18 Page 19 Page 20 Report of the administrative manager Page 21 Page 22 Agricultural economics Page 23 Page 24 Page 25 Page 26 Page 27 Page 28 Page 29 Page 30 Page 31 Page 32 Page 33 Page 34 Page 35 Page 36 Page 37 Page 38 Page 39 Page 40 Page 41 Agricultural engineering Page 42 Page 43 Page 44 Page 45 Page 46 Page 47 Page 48 Page 49 Agronomy Page 50 Page 51 Page 52 Page 53 Page 54 Page 55 Page 56 Page 57 Page 58 Page 59 Page 60 Page 61 Page 62 Page 63 Page 64 Page 65 Page 66 Page 67 Animal science Page 68 Page 69 Page 70 Page 71 Page 72 Page 73 Page 74 Page 75 Page 76 Page 77 Page 78 Page 79 Page 80 Page 81 Page 82 Page 83 Page 84 Page 85 Page 86 Botany Page 87 Page 88 Page 89 Dairy science Page 90 Page 91 Page 92 Page 93 Page 94 Page 95 Page 96 Page 97 Page 98 Page 99 Editorial Page 100 Page 101 Page 102 Page 103 Page 104 Page 105 Page 106 Page 107 Page 108 Page 109 Page 110 Page 111 Page 112 Page 113 Entomology Page 114 Page 115 Page 116 Page 117 Page 118 Page 119 Page 120 Food technology and nutrition Page 121 Page 122 Page 123 Page 124 Page 125 Page 126 Page 127 Page 128 Forestry Page 129 Page 130 Page 131 Page 132 Page 133 Page 134 Page 135 Page 136 Page 137 Fruit crops Page 138 Page 139 Page 140 Page 141 Page 142 Library Page 143 Page 144 Page 145 Ornamental horticulture Page 146 Page 147 Page 148 Page 149 Page 150 Page 151 Page 152 Page 153 Page 154 Page 155 Plant pathology Page 156 Page 157 Page 158 Page 159 Page 160 Page 161 Page 162 Page 163 Plant science station Page 164 Poultry science Page 165 Page 166 Page 167 Page 168 Page 169 Page 170 Soils Page 171 Page 172 Page 173 Page 174 Page 175 Page 176 Page 177 Page 178 Page 179 Page 180 Page 181 Page 182 Page 183 Page 184 Page 185 Page 186 Page 187 Page 188 Statistical section Page 189 Vegetable crops Page 190 Page 191 Page 192 Page 193 Page 194 Page 195 Page 196 Page 197 Page 198 Veterinary science department Page 199 Page 200 Page 201 Page 202 Page 203 Page 204 Central Florida station Page 205 Page 206 Page 207 Page 208 Page 209 Page 210 Page 211 Page 212 Page 213 Page 214 Page 215 Page 216 Page 217 Page 218 Page 219 Page 220 Page 221 Page 222 Citrus station Page 223 Page 224 Page 225 Page 226 Page 227 Page 228 Page 229 Page 230 Page 231 Page 232 Page 233 Page 234 Page 235 Page 236 Page 237 Page 238 Page 239 Page 240 Page 241 Page 242 Page 243 Page 244 Page 245 Page 246 Page 247 Page 248 Page 249 Page 250 Page 251 Page 252 Page 253 Page 254 Page 255 Everglades station Page 256 Page 257 Page 258 Page 259 Page 260 Page 261 Page 262 Page 263 Page 264 Page 265 Page 266 Page 267 Page 268 Page 269 Page 270 Page 271 Page 272 Page 273 Page 274 Page 275 Page 276 Page 277 Page 278 Page 279 Page 280 Page 281 Page 282 Indian River field laboratory Page 283 Page 284 Page 285 Page 286 Page 287 Page 288 Page 289 Page 290 Plantation field laboratory Page 291 Page 292 Page 293 Page 294 Page 295 Page 296 Page 297 Page 298 Page 299 Gulf Coast station Page 300 Page 301 Page 302 Page 303 Page 304 Page 305 Page 306 Page 307 Page 308 Page 309 Page 310 Page 311 Page 312 Page 313 Page 314 Page 315 Page 316 Page 317 Page 318 Page 319 Page 320 North Florida station Page 321 Page 322 Page 323 Page 324 Page 325 Page 326 Page 327 Page 328 Page 329 Page 330 Page 331 Page 332 Page 333 Page 334 Range cattle station Page 335 Page 336 Page 337 Page 338 Page 339 Page 340 Page 341 Page 342 Page 343 Page 344 Page 345 Page 346 Sub-tropical experiment station Page 347 Page 348 Page 349 Page 350 Page 351 Page 352 Page 353 Page 354 Page 355 Page 356 Page 357 Page 358 Page 359 Suwannee Valley station Page 360 Page 361 Page 362 Page 363 West central Florida station Page 364 West Florida station Page 365 Page 366 Page 367 Page 368 Page 369 Page 370 Federal-state frost warning service Page 371 Page 372 Page 373 Potato investigations laboratory Page 374 Page 375 Page 376 Page 377 Page 378 Strawberry investigations laboratory Page 379 Page 380 Watermelon and grape investigations laboratory Page 381 Page 382 Page 383 Page 384 Page 385 Page 386 Index Page 387 Page 388 Page 389 Page 390 Page 391 Page 392 Page 393 Page 394 Page 395 Page 396 Page 397 Page 398 Page 399 |
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UNIVERSITY OF FLORIDA GAINESVILLE, FLORIDA AGRICULTURAL EXPERIMENT STATIONS ANNUAL REPORT FOR THE FISCAL YEAR ENDING JUNE 30, 1961 CONTENTS Page Report of the Director ..................... .....-..... --... .................-...... 13 Report of the Administrative Manager ...--...--- ...----- ---... 21 MAIN STATION: Agricultural Economics .-... .........----....- ..... ..---- 23 Agricultural Engineering ..-...... .. ................................. -42 Agronomy ................-- --- .... ------ 50 Animal Science --....-- --.........-.........---- -- 68 Botany .-..--- .... ............ 87 Dairy Science ................ ......- ..........- ----- ... .......-- -- -. 90 Editorial ...........................-...-..-..-. --.... .. .. .. 100 Entom ology ............. -.......... ...... ....-.-- ...- ...- 114 Food Technology and Nutrition ...................... -..-----.. 121 Forestry ............... ................... .. .. ..... ... ..... .- 129 Fruit Crops ... ..............- ......-.... --.-. ......- -... .-. 138 Library ....................................... ..................... 143 Ornamental Horticulture ....... .. ...-- ..- .. ....-.. --.... -... 146 Plant Pathology ..................... ........... .....----.. 156 Plant Science Section .............. ......... .... -.-.. ....... 164 Poultry Science ....-.. ... ......-..~.-- ..---. ..... 165 Soils ..............-... ....... ..-..- ..... -. ...- ..... -- --- -- 171 Statistical Section ........... ... .. .... ... ..189 Vegetable Crops ..............-................ ............... 190 Veterinary Science ................ ... .--........- ..------ ..-.. .-- 199 BRANCH STATIONS: Central Florida Station ................ .--........-- ---- ...... .. 205 Citrus Station ............-.....--........-....-..- ..-. ---.-.-. --. 223 Everglades Station ...................-- ... -..--- ... -..-- ... .. 256 Indian River Field Laboratory ........................------.. ... ....-. 283 Plantation Field Laboratory .......-..-..... ..-.-....-------.----- 291 Gulf Coast Station ..................-...-..... --..--..-.---.--. 300 South Florida Field Laboratory ..........-...---- ---..--... ...... .. 317 North Florida Station .......-- ..... ---...........-.. --- 321 Marianna Field Laboratory .........-............------..-..-..----- 333 Range Cattle Station ..............-.....--..-.....-..--. ---.--.. 335 Sub-Tropical Station ........--...--......----....... ---..-..-. 347 Suwannee Valley Station ...........-..----.....-...---.------------ 360 West Central Florida Station .......................----.--- --------..-.-- 364 W est Florida Station .....-...-...-- ..- .........-- .--... .... ......... 365 FIELD LABORATORIES: Federal-State Frost Warning Service ...............---. Potato Investigations Laboratory ..................-........... Strawberry Investigations Laboratory ..............-......... Watermelon and Grape Investigations Laboratory . .... 371 --..... 374 ....--- 379 ........ 381 AGRICULTURAL EXPERIMENT STATION STAFF BOARD OF CONTROL J. J. Daniel, Chairman, Jacksonville James J. Love, Quincy Ralph L. Miller, Orlando Joe K. Hays, Winter Haven Frank H. Buchanan, Marianna S. Kendrick Guernsey, Jacksonville James D. Camp, Ft. Lauderdale J. Broward Culpepper, Executive Director, Tallahassee ADMINISTRATION J. W. Reitz, Ph.D., President W. M. Fifield, M.S., Provost for Agriculture J. R. Beckenbach, Ph.D., Director J. W. Sites, Ph.D., Associate Director H. H. Wilkowske, Ph.D., Assistant Director D. R. Bryant, Jr., A.B., Administrative Manager G. R. Freeman, M.S.A., Superintendent of Field Operations W. H. Jones, M.Agr., Assistant Superintendent of Field Operations ACADEMIC STAFF The following abbreviations after name and title of Experiment Sta- tion Staff indicate cooperation with other organizations: Coll. University of Florida College of Agriculture Ext. University of Florida Agricultural Extension Service USDA United States Department of Agriculture USWB United States Weather Bureau FCC Florida Citrus Commission SPB State Plant Board MAIN STATION, GAINESVILLE Agricultural Economics Department H. G. Hamilton, Ph.D., Agricultural Economist and Head; also Coll. and Ext. H. B. Clark, Ph.D., Agricultural Economist; also Coll. M. R. Godwin, Ph.D., Marketing Economist; also Coll. R. E. L. Greene, Ph.D., Agricultural Economist; also Coll. J. R. Greenman, B.S.A., L.L.B., Agricultural Economist; also Coll. F. T. Hady, B.A., Agricultural Economist, USDA W. K. McPherson, M.S., Agricultural Economist; also Coll. J. B. Owens, B.S., Agricultural Statistician, USDA, Orlando L. A. Reuss, M.S., Agricultural Economist, USDA Z. Savage, M.S.A., Agricultural Economist A. H. Spurlock, M.S.A., Agricultural Economist J. C. Townsend, B.S.A., Agricultural Statistician, Orlando, USDA D. E. Alleger, M.S., Associate Agricultural Economist D. L. Brooke, Ph.D., Associate Agricultural Economist G. L. Capel, Ph.D., Assoc. Agricultural Economist, USDA C. E. Murphree, D.P.A., Associate Agricultural Economist; also Coll. G. N. Rose, B.S., Associate Agricultural Economist, Orlando C. N. Smith, Ph.D., Associate Agricultural Economist; also Coll. W. T. Manley, Ph.D., Assistant Agricultural Economist, USDA W. B. Riggan, B.S., Assistant Agricultural Economist; also Coll. G. A. Rowe, B.S.A., Asst. Agricultural Statistician, USDA, Orlando R. G. Stout, Ph.D., Assistant Agricultural Economist, Orlando R. R. Hancock, M.S., Assistant Agricultural Statistician, USDA L. D. Marquis, Jr., B.S.A., Assistant Agricultural Statistician, USDA H. G. Witt, M.S.A., Assistant Agricultural Statistician, USDA F. W. Chapman, M.S., Assistant in Agricultural Economics, USDA G. G. Goshorn, B.S., Assistant in Agricultural Economics, Orlando Mrs. B. S. Lloyd, B.S., Assistant in Agricultural Economics E. G. Close, M.S.A., Int. Assistant in Agricultural Economics A. B. Krienke, M.S., Int. Assistant in Agricultural Economics Agricultural Engineering Department D. T. Kinard, Ph.D., Agricultural Engineer and Head; also Coll. and Ext. R. E. Choate, M.S.A., Agricultural Engineer; also Coll. J. M. Myers, M.S.A., Agricultural Engineer; also Coll. E. K. Bowman, B.S., Associate Industrial Engineer, USDA W. G. Grizzell, B.I.E., Assistant Agricultural Engineer, USDA E. S. Holmes, M.S., Assistant Agricultural Engineer; also Coll. J. B. Richardson, M.S., Assistant Agricultural Engineer; also Coll. I. J. Ross, Ph.D., Assistant Agricultural Engineer; also Coll. G. E. Yost, B.S., Assistant Agricultural Engineer, USDA Agronomy Department F. H. Hull, Ph.D., Agronomist and Head K. D. Butson, M.S., State Climatologist, USWB W. A. Carver, Ph.D., Agronomist H. C. Harris, Ph.D., Agronomist G. B. Killinger, Ph.D., Agronomist E. G. Rodgers, Ph.D., Agronomist; also Coll. F. Clark, M.S.A., Associate Agronomist E. S. Horner, Ph.D., Associate Agronomist; also Coll. J. R. Edwardson, Ph.D., Assistant Agronomist; also Coll. K. Hinson, Ph.D., Assistant Agronomist, USDA D. B. Linden, Ph.D., Assistant Agronomist; also Coll. A. J. Norden, Ph.D., Assistant Agronomist; also Coll. P. L. Pfahler, Ph.D., Assistant Agronomist G. M. Prine, Ph.D., Assistant Agronomist 0. C. Ruelke, Ph.D., Assistant Agronomist; also Coll. V. N. Schroder, Ph.D., Assistant Agronomist; also Coll. S. H. West, Ph.D., Assistant Agronomist, USDA M. Wilcox, M.S., Assistant Agronomist Animal Science Department T. J. Cunha, Ph.D., Animal Husbandman and Head; also Coll. and Ext. G. K. Davis, Ph.D., Animal Nutritionist; also Coll. and Director of Nu- clear Science M. Koger, Ph.D., Animal Husbandman; also Coll. R. L. Shirley, Ph.D., Biochemist; also Coll. L. R. Arrington, Ph.D., Associate Animal Nutritionist; also Coll. J. P. Feaster, Ph.D., Associate Biochemist J. F. Hentges, Jr., Ph.D., Associate Animal Husbandman; also Coll. A. Z. Palmer, Ph.D., Associate Animal Husbandman; also Coll. H. D. Wallace, Ph.D., Associate Animal Husbandman; also Coll. A. C. Warnick, Ph.D., Associate Physiologist; also Coll. C. B. Ammerman, Ph.D., Assistant Animal Nutritionist J. W. Carpenter, Ph.D., Assistant Animal Husbandman G. E. Combs, Ph.D., Assistant Animal Husbandman; also Coll. P. E. Loggins, M.S., Assistant Animal Husbandman; also Coll. D. L. Wakeman, M.S.A., Assistant Animal Husbandman; also Coll. Botany Department G. R. Noggle, Ph.D., Botanist and Head; also Coll. T. E. Humphreys, Ph.D., Associate Biochemist G. J. Fritz, Ph.D., Assistant Plant Physiologist Yoneo Sagawa, Ph.D., Assistant Botanist; also Coll. D. B. Ward, Ph.D., Assistant Botanist; also Coll. Dairy Science Department E. L. Fouts, Ph.D., Dairy Technologist and Head; also Coll. R. B. Becker, Ph.D., Dairy Husbandman; also Coll. S. P. Marshall, Ph.D., Dairy Husbandman; also Coll. L. E. Mull, Ph.D., Dairy Technologist; also Coll. W. A. Krienke, M.S., Associate Dairy Technologist; also Coll. J. M. Wing, Ph.D., Associate Dairy Husbandman; also Coll. K. L. Smith, Ph.D., Assistant Dairy Technologist; also Coll. C. J. Wilcox, Ph.D., Assistant Dairy Husbandman; also Coll. West Florida Dairy Unit, Chipley J. B. White, B.S.A., Associate Dairy Husbandman Editorial Department M. H. Sharpe, Ph.D., Associate Editor and Acting Head of Dept.; also Ext. W. G. Mitchell, M.S.A., Associate Editor; also Ext. W. J. Brown, B.S., Assistant Editor R. C. Orr, B.S., Assistant Editor Entomology Department A. N. Tissot, Ph.D., Entomologist and Head L. C. Kuitert, Ph.D., Entomologist V. G. Perry, Ph.D., Nematologist; also Coll. A. A. DiEdwardo, Ph.D., Assistant Nematologist S. H. Kerr, Ph.D., Assistant Entomologist F. A. Robinson, M.S., Assistant Apiculturist R. E. Waites, Ph.D., Assistant Entomologist R. C. Wilkinson, M.S., Assistant Entomologist Food Technology and Nutrition Department R. A. Dennison, Ph.D., Biochemist and Head; also Coll. R. B. French, Ph.D., Biochemist R. K. Showalter, M.S., Horticulturist; also Coll. C. B. Hall, Ph.D., Associate Horticulturist C. H. Van Middelem, Ph.D., Associate Biochemist F. W. Knapp, Ph.D., Assistant Biochemist; also Coll. G. D. Kuhn, M.S., Assistant Food Microbiologist; also Coll. H. P. Pan, Ph.D., Assistant Biochemist R. C. Robbins, Ph.D., Assistant Biochemist; also Coll. Ruth O. Townsend, R.N., Assistant in Nutrition Forestry Department C. M. Kaufman, Ph.D., Forester and Head; also Coll. C. G. Geltz, M.S., Forester; also Coll. J. W. Miller, M.S.F., Forester; also Coll. K. R. Swinford, Ph.D., Forester; also Coll. S. L. Beckwith, Ph.D., Associate Forester; also Coll. P. W. Frazer, M.F., Associate Forester; also Coll. J. B. Huffman, D.F., Associate Forester; also Coll. R. B. Smith, Ph.D., Associate Forester; also Coll. E. T. Sullivan, D.F., Associate Forester; also Coll. J. W. Willingham, Ph.D., Associate Forester; also Coll. R. E. Goddard, Ph.D., Assistant Geneticist; also Coll. D. M. Post, M.S.F., Assistant Forester; also Coll. R. K. Strickland, M.S., Int. Assistant in Forestry W. J. Peters, B.S., Int. Assistant in Forestry Fruit Crops Department A. H. Krezdorn, Ph.D., Horticulturist and Head; also Ext. J. S. Shoemaker, Ph.D., Horticulturist R. H. Sharpe, M.S., Horticulturist R. H. Biggs, Ph.D., Assistant Biochemist J. F. Gerber, Ph.D., Assistant Climatologist Library Ida K. Cresap, Librarian A. C. Strickland, Assistant in Library Janie L. Tyson, Assistant in Library Ornamental Horticulture Department E. W. McElwee, Ph.D., Horticulturist and Head; also Coll. and Ext. R. D. Dickey, M.S.A., Horticulturist G. C. Horn, Ph.D., Associate Turf Technologist; also Coll. J. N. Joiner, Ph.D., Assistant Ornamental Horticulturist; also Coll. S. E. McFadden, Jr., Ph.D., Assistant Horticulturist T. J. Sheehan, Ph.D., Assistant Horticulturist; also Coll. Plant Pathology Department P. Decker, Ph.D., Plant Pathologist and Head; also Coll. H. H. Luke, Ph.D., Plant Pathologist, USDA H. N. Miller, Ph.D., Plant Pathologist E. West, M.S., Botanist and Mycologist; also Coll. C. W. Anderson, Ph.D., Associate Virologist D. A. Roberts, Ph.D., Associate Plant Pathologist; also Coll. A. A. Cook, Ph.D., Assistant Plant Pathologist M. K. Corbett, Ph.D., Assistant Virologist T. E. Freeman, Ph.D., Assistant Plant Pathologist R. F. Stouffer, Ph.D., Assistant Virologist Plant Science Section A. T. Wallace, Ph.D., Geneticist in Charge Poultry Science Department N. R. Mehrhof, M.Agr., Poultry Husbandman and Head; also Coll. and Ext. R. H. Harms, Ph.D., Associate Poultry Husbandman; also Coll. R. E. Cook, Ph.D., Assistant Poultry Husbandman; also Coll. F. R. Tarver, Jr., M.S., Assistant Poultry Husbandman; also Coll. (on leave of absence) Soils Department F. B. Smith, Ph.D., Microbiologist and Head; also Coll. N. Gammon, Jr., Ph.D., Soils Chemist J. R. Neller, Ph.D., Soils Chemist W. L. Pritchett, Ph.D., Soils Technologist G. M. Volk, Ph.D., Soils Chemist W. G. Blue, Ph.D., Associate Biochemist R. E. Caldwell, Ph.D., Associate Chemist; also Coll. C. F. Eno, Ph.D., Associate Soils Microbiologist J. G. A. Fiskell, Ph.D., Associate Biochemist; also Coll. L. C. Hammond, Ph.D., Associate Soils Physicist; also Coll. R. G. Leighty, B.S., Associate Soils Surveyor W. K. Robertson, Ph.D., Associate Chemist H. L. Breland, Ph.D., Assistant Soils Chemist G. A. Brown, B.S.A., Assistant Soils Surveyor T. C. Mathews, B.S.A., Assistant Soils Surveyor H. L. Popenoe, Ph.D., Assistant Soils Chemist; also Coll. H. W. Winsor, B.S.A., Assistant Chemist T. L. Yuan, Ph.D., Assistant Chemist Statistical Section A. E. Brandt, Ph.D., Statistician and Head Vegetable Crops Department F. S. Jamison, Ph.D., Horticulturist and Head; also Coll. and Ext. A. P. Lorz, Ph.D., Horticulturist; also Coll. V. F. Nettles, Ph.D., Horticulturist; also Coll. B. D. Thompson, Ph.D., Associate Horticulturist; also Coll. D. D. Gull, Ph.D., Assistant Horticulturist L. H. Halsey, M.S.A., Assistant Horticulturist S. J. Locascio, Ph.D., Assistant Horticulturist; also Coll. Veterinary Science Department C. F. Simpson, D.V.M., Veterinarian and Acting Head; also Coll. D. A. Sanders, D.V.M., Veterinarian L. E. Swanson, D.V.M., Pathologist; also Coll. A. J. Kniazeff, D.V.M., Associate Virologist D. D. Cox, Ph.D., Assistant Parasitologist; also Coll. F. H. White, Ph.D., Assistant Bacteriologist W. M. Stone, Jr., M.S., Assistant in Parasitology Jane Beck Walker, M.S., Assistant in Bacteriology H. Kitchen, D.VM., Int. Research Associate BRANCH STATIONS CENTRAL FLORIDA STATION, Sanford J. W. Wilson, Sc.D., Entomologist in Charge P. J. Westgate, Ph.D., Horticulturist J. F. Darby, Ph.D., Associate Plant Pathologist W. T. Scudder, Ph.D., Associate Horticulturist R. B. Forbes, Ph.D., Assistant Soils Chemist H. L. Rhoades, Ph.D., Assistant Nematologist B. F. Whitner, Jr., B.S.A., Assistant Horticulturist CITRUS STATION, Lake Alfred H. J. Reitz, Ph.D., Horticulturist in Charge L. L. Sebring, M.S., Assistant in Library Harvesting and Packing Section E. F. Hopkins, Ph.D., Plant Physiologist, FCC G. E. Coppock, M.S., Associate Agricultural Engineer, FCC F. W. Hayward, Ph.D., Associate Biochemist S. V. Ting, Ph.D., Associate Biochemist A. A. McCornack, M.S., Assistant Horticulturist, FCC M. F. Oberbacher, Ph.D., Assistant Plant Physiologist, FCC Production Section D. W. Clancy, Ph.D., Entomologist, USDA E. P. DuCharme, Ph.D., Plant Pathologist A. W. Feldman, Ph.D., Plant Pathologist L. C. Knorr, Ph.D., Plant Pathologist (on leave of absence) M. H. Muma, Ph.D., Entomologist W. C. Price, Ph.D., Virologist W. A. Simanton, Ph.D., Entomologist R. F. Suit, Ph.D., Plant Pathologist A. C. Tarjan, Ph.D., Nematologist W. L. Thompson, B.S., Entomologist H. W. Ford, Ph.D., Associate Horticulturist R. B. Johnson, Ph.D., Associate Entomologist C. D. Leonard, Ph.D., Associate Horticulturist W. F. Spencer, Ph.D., Associate Soils Chemist I. Stewart, Ph.D., Associate Biochemist H. M. Vines, Ph.D., Associate Biochemist, FCC R. F. Brooks, Ph.D., Assistant Entomologist Francine E. Fisher, M.S., Assistant Plant Pathologist R. W. Hanks, Ph.D., Assistant Plant Pathologist C. I. Hannon, Ph.D., Assistant Nematologist C. H. Hendershott, M.S., Assistant Plant Physiologist, FCC R. C. Koo, Ph.D., Assistant Horticulturist D. W. Kretchman, M.S., Assistant Horticulturist A. P. Pieringer, Ph.D., Assistant Horticulturist H. 0. Sterling, M.S., Assistant Horticulturist L. B. Anderson, Jr., B.S.A., Assistant in Entomology-Pathology J. W. Davis, B.S.A., Assistant in Entomology-Pathology G. J. Edwards, B.A., Assistant in Chemistry T. B. Hallam, B.S., Assistant in Entomology-Pathology H. I. Holtsberg, B.S.A., Assistant in Entomology-Pathology M. D. Maraulja, B.S., Assistant in Chemistry, FCC K. G. Townsend, B.S.A., Assistant in Entomology-Pathology R. J. Collins, M.S., Int. Assistant Horticulturist K. C. Li, Ph.D., Int. Assistant Food Technologist Processing Section C. D. Atkins, B.S., Chemist, FCC J. W. Kesterson, M.S., Chemist E. L. Moore, Ph.D., Chemist, FCC R. W. Olsen, B.S., Biochemist R. Patrick, Ph.D., Bacteriologist A. H. Rouse, M.S., Pectin Chemist F. W. Wenzel, Jr., Ph.D., Chemist R. C. Bullock, Ph.D., Associate Entomologist R. Hendrickson, B.S., Associate Chemist W. F. Newhall, Ph.D., Associate Biochemist R. W. Wolford, M.A., Associate Chemist, FCC J. A. Attaway, Ph.D., Assistant Chemist, FCC M. H. Dougherty, B.S., Assistant Chemical Engineer, FCC E. C. Hill, B.S.A., Assistant Bacteriologist, FCC R. L. Huggart, B.S., Assistant Chemist, FCC S. K. Long, Ph.D., Assistant Industrial Bacteriologist G. E. Alberding, B.S., Assistant in Chemistry, FCC R. W. Barron, B.A., Assistant in Chemistry, FCC Indian River Field Laboratory, Box 1351, Fort Pierce M. Cohen, Ph.D., Associate Plant Pathologist R. R. Hunziker, Ph.D., Assistant Soils Chemist EVERGLADES STATION, Box 37, Belle Glade W. T. Forsee, Jr., Ph.D., Chemist in Charge Fiber and Engineering Section R. V. Allison, Ph.D., Fiber Technologist M. H. Byrom, M.S., Agricultural Engineer, USDA D. W. Fisher, M.S., Associate Agronomist, USDA C. C. Seale, D.I.C.T.A., Associate Agronomist T. E. Summers, Ph.D., Associate Plant Pathologist, USDA H. D. Whittemore, B.S.A.E., Associate Agricultural Engineer, USDA T. W. Casselman, M.S., Assistant Agricultural Engineer J. F. Joyner, Assistant Agronomist, USDA F. D. Wilson, Ph.D., Assistant Plant Geneticist, USDA J. R. Crockett, B.S., Int. Assistant in Animal Husbandry Soils and Chemistry Section H. W. Burdine, Ph.D., Assistant Soils Chemist C. C. Hortenstine, Ph.D., Assistant Soils Chemist F. H. Thomas, Ph.D., Assistant Chemist Horticulture Section V. L. Guzman, Ph.D., Associate Horticulturist E. A. Wolf, M.S., Associate Horticulturist J. R. Orsenigo, Ph.D., Assistant Horticulturist Agronomy Section V. E. Green, Jr., Ph.D., Associate Agronomist R. J. Allen, Jr., Ph.D., Assistant Agronomist F. leGrand, M.S., Assistant Agronomist Plant Pathology Section P. L. Thayer, Ph.D., Assistant Plant Pathologist C. Wehlburg, Ph.D., Assistant Plant Pathologist Entomology Section W. G. Genung, M.S., Associate Entomologist E. D. Harris, Jr., Ph.D., Assistant Entomologist Animal Husbandry Section R. W. Kidder, M.S., Animal Husbandman H. L. Chapman, Jr., Ph.D., Associate Animal Husbandman C. E. Haines, Ph.D., Assistant Animal Husbandman Indian River Field Laboratory, Box 1351, Fort Pierce N. C. Hayslip, B.S.A., Entomologist A. E. Kretschmer, Jr., Ph.D., Associate Agronomist R. E. Stall, Ph.D., Assistant Plant Pathologist Plantation Field Laboratory, 5305 S. W. 12th St., Fort Lauderdale F. T. Boyd, Ph.D., Agronomist J. C. Stephens, B.S., Drainage Engineer, USDA H. I. Borders, Ph.D., Associate Plant Pathologist R. R. Smalley, M.S., Research Associate E. H. Stewart, B.S., Associate Soils Physicist, USDA R. D. Blackburn, B.S., Assistant Agronomist, USDA H. Y. Ozaki, Ph.D., Assistant Horticulturist D. E. Seaman, Ph.D., Assistant Plant Pathologist, USDA L. W. Weldon, Ph.D., Assistant Agronomist, USDA GULF COAST STATION, Box 2125 Manatee Station, Bradenton E. L. Spencer, Ph.D., Soils Chemist in Charge E. G. Kelsheimer, Ph.D., Entomologist R. 0. Magie, Ph.D., Plant Pathologist J. M. Walter, Ph.D., Plant Pathologist C. M. Geraldson, Ph.D., Associate Soils Chemist D. G. A. Kelbert, Associate Horticulturist D. S. Burgis, M.S.A., Assistant Horticulturist C. R. Jackson, Ph.D., Assistant Plant Pathologist J. P. Jones, Ph.D., Assistant Plant Pathologist Amegda J. Overman, M.S., Assistant Soils Microbiologist W. E. Waters, Ph.D., Assistant Horticulturist S. S. Woltz, Ph.D., Assistant Horticulturist South Florida Field Laboratory, Box 973, Immokalee P. H. Everett, Ph.D., Assistant Soils Chemist NORTH FLORIDA STATION, Quincy W. H. Chapman, M.S., Agronomist in Charge R. R. Kincaid, Ph.D., Plant Pathologist W. C. Rhoades, M.S., Entomologist L. G. Thompson, Jr., Ph.D., Soils Chemist F. S. Baker, Jr., M.S.A., Associate Animal Husbandman R. W. Wallace, B.S., Associate Agronomist C. E. Dean, Ph.D., Assistant Agronomist D. T. Sechler, Ph.D., Assistant Agronomist W. B. Tappan, M.S.A., Assistant Entomologist W. D. Woodward, M.S., Assistant Soils Chemist H. W. Young, Ph.D., Assistant Horticulturist Marianna Field Laboratory R. W. Lipscomb, M.S., Associate Agronomist RANGE CATTLE STATION, Ona W. G. Kirk, Ph.D., Vice-Director in Charge E. M. Hodges, Ph.D., Agronomist C. L. Dantzman, Ph.D., Assistant Soils Chemist J. E. McCaleb, Ph.D., Assistant Agronomist F. M. Peacock, M.S., Assistant Animal Husbandman SUB-TROPICAL STATION, Route 1, Box 560, Homestead G. D. Ruehle, Ph.D., Vice-Director in Charge R. A. Conover, Ph.D., Plant Pathologist D. 0. Wolfenbarger, Ph.D., Entomologist T. W. Young, Ph.D., Horticulturist R. W. Harkness, Ph.D., Associate Chemist J. Popenoe, Ph.D., Associate Horticulturist R. M. Baranowski, Ph.D., Assistant Entomologist C. W. Campbell, Ph.D., Assistant Horticulturist L. A. McFadden, Ph.D., Assistant Plant Pathologist J. C. Noonan, M.S., Assistant Horticulturist P. G. Orth, Ph.D., Assistant Soils Chemist J. W. Strobel, Ph.D., Assistant Plant Pathologist SUWANNEE VALLEY STATION, Box 630, Live Oak H. W. Lundy, B.S.A., Associate Agronomist in Charge WEST CENTRAL FLORIDA STATION, Brooksville W. C. Burns, M.S., Assistant Animal Husbandman, Acting in Charge, USDA WEST FLORIDA STATION, Route 3, Jay C. E. Hutton, Ph.D., Vice-Director in Charge R. L. Smith, M.S., Associate Agronomist L. S. Dunavin, Jr., Ph.D., Assistant Agronomist M. C. Lutrick, Ph.D., Assistant Agronomist FIELD LABORATORIES Potato Investigations Laboratory, Box 728, Hastings A. H. Eddins, Ph.D., Plant Pathologist in Charge E. N. McCubbin, Ph.D., Horticulturist D. R. Hensel, Ph.D., Assistant Soils Chemist R. B. Workman, Ph.D., Assistant Entomologist Pecan Investigations Laboratory, Box A, Monticello J. R. Large, M.S., Associate Plant Pathologist A. M. Phillips, B.S., Associate Entomologist; also USDA Strawberry Investigations Laboratory, Plant City (Box 2386, Lakeland) A. N. Brooks, Ph.D., Plant Pathologist Watermelon and Grape Investigations Laboratory, Box 321, Leesburg J. M. Crall, Ph.D., Plant Pathologist in Charge C. H. Curran, D.Sc., Entomologist W. C. Adlerz, Ph.D., Assistant Entomologist J. A. Mortensen, Ph.D., Assistant Geneticist N. C. Schenck, Ph.D., Assistant Plant Pathologist L. H. Stover, Assistant in Horticulture Weather Forecasting Service, Box 1058, Lakeland W. 0. Johnson, B.S., Meteorologist in Charge, USWB A. W. Smith, Special Meteorologist Observer L. E. Hughes, M.S., Associate Meteorologist, USWB L. L. Benson, B.S., Assistant Meteorologist, USWB G. R. Davis, B.S., Assistant Meteorologist R. H. Dean, Assistant Meteorologist, USWB J. G. Georg, B.S., Assistant Meteorologist, USWB W. F. Mincey, Assistant Meteorologist, USWB B. H. Moore, B.A., Assistant Meteorologist, USWB O. N. Norman, B.S., Assistant Meteorologist, USWB R. T. Sherouse, Assistant Meteorologist, USWB W. R. Wallis, B.S., Assistant Meteorologist H. E. Yates, Assistant Meteorologist, USWB REPORT OF THE DIRECTOR Although interest in Science is mounting rapidly, interest in biological and agricultural sciences, excepting human health, is at low ebb. Agri- cultural surpluses are partly responsible, and have resulted in a bad pub- lic image for agriculture generally. It hasn't helped that national agricul- tural policies have been made political issues. Perhaps more important, however, is the glamour of the scientific competition. Food and clothing are rather prosaic as compared with moon rockets and satellites. National prestige is involved in these rocket and satellite programs. More than prestige is involved in our agriculture; our future as a nation and leader of nations is directly involved. Present surpluses are very transient things; if our expanding population is to be fed and clothed, our agricultural research at all levels should be expanded at once. The problems facing Agriculture are becoming increasingly complex and dif- ficult. The financial status of the Florida Station has retrogressed during the past year. Federal Grant appropriations about held their own; State ap- propriations for operating funds were reduced, and needed building facil- ities were ignored. In spite of this, the research operation continues to open doors which will be reflected in great advances for Florida's agriculture. Underfinanc- ing only means that fewer such doors can be opened than otherwise. We can be proud of the fact that many presently important crops would not be here without past research by the staff of the Experiment Stations. Every farm commodity has received major help; specific important re- search contributions can be cited with each one. Our citrus, beef cattle, sugar, dairy, poultry, vegetable and ornamental industries routinely use Station research findings; without these scientific contributions none of these income producers could exist as major industries. Forestry, as a continuing industry and income producer, is approach- ing a cross-roads in Florida. The state has been pretty well logged off. The future must be a farm forest operation, and much research is need- ed if it is to continue long as a major economic asset. We must urge continued and expanded investments in agricultural re- search. Agribusiness is Florida's biggest industry; only added public support for research can keep it in this position. CAPITAL IMPROVEMENTS As part of the Board of Control "Role and Scope" study during the past year, a re-evaluation of physical needs was made. The situation is something less than adequate since major capital improvements have been virtually at a standstill for several years. The study showed that almost one-fourth of our scientific staff are housed in inadequate quar- ters. Another study of miscellaneous small buildings showed 7 percent currently inadequate which would require slightly more than one-half million dollars to replace. Only significant appropriations for major build- ings, facilities and land will correct this shortage which is adversely af- fecting the progress of the over-all Station research program. Facilities completed during the year included an experimental pilot- model growth room which provided invaluable information to be used in the development of the much needed basic plant science research facil- ity; a toxicology laboratory for entomological research; and a few sheds,: Florida Agricultural Experiment Stations shelters, barns, silos, feed rooms and greenhouses. At the West Florida Station construction is now underway of a laborer's cottage, silos, barn and equipment shelter provided by a $30,000 special appropriation of the 1959 legislature. RESEARCH PROGRAM As Florida's agriculture continues to grow (at a rate 30 per cent fast- er than the national average) new problems constantly occur. A well or- ganized and flexible research program is underway to anticipate and solve these pressing problems through the use of specific planned re- search projects. Many of the projects are cooperative, being planned and conducted using the team approach by two or more researchers in more than one department, branch station or field laboratory. Such work is carefully coordinated and evaluated for most efficient use of research funds as well as most effective way to solve the problems. The current research program consists of 435 approved projects plus additional preliminary non-projected unnumberedd) research projects, most of which briefly are reported herein. During the year 74 projects were initiated and 62 terminated. Currently there are 12 regional re- search projects underway. Since the projects are reported by number, to obtain complete information on a given problem, commodity or process, which may have received attention by a number of scientists at several locations, the reader should consult the index under the various subjects of interest. During the year a number of staff research planning conferences were held in specific subject-matter areas. Field days, short courses and conferences also were held by various departments, branch stations and field laboratories at which time research underway and results were re- ported to the public. All in all, the Station system has provided outstand- ing service to growers, ranchers and related agricultural industries throughout Florida as evidenced by the research contributions described in the following report. STAFF CHANGES Appointments Dale Robert Hensel, Assistant Soils Chemist, Potato Investigations Lab., July 1, 1960 Gerald D. Kuhn, Assistant Food Microbiologist, Food Tech. and Nutr. Dept., July 1, 1960 Shurley Allen Poole, Jr., Int. Asst. in Ag. Economics, Ag. Econ. Dept., July 1, 1960 Dale Truman Sechler, Assistant Agronomist, North Fla. Station, July 1, 1960 Frederick W. Knapp, Asst. Biochemist, Food Tech. and Nutr. Dept., Aug. 1, 1960 Glenn Gilbert Goshorn, Asst. in Ag. Economics, Ag. Econ. Dept., Aug. 1, 1960 Joe Richard Crockett, Int. Asst. in Animal Husbandry, Everglades Sta- tion, Aug. 16, 1960 Anthony Alexander Di Edwardo, Asst. Nematologist, Ent. Dept., Aug. 16, 1960 Richard James Collins, Int. Asst. Horticulturist, Citrus Station, Sept. 1, 1960 Matthew Daniel Maraulja, Asst. in Chemistry, Citrus Station, Sept. 1, 1960 Annual Report, 1961 Kenneth L. Smith, Asst. Dairy Technologist, Dairy Sci. Dept., Sept. 1, 1960 Ray Kenneth Strickland, Int. Asst. in Forestry, Forestry Dept., Sept. 1, 1960 Robert Cleveland Wilkinson, Asst. Entomologist, Ent. Dept., Sept. 1, 1960 Herbert Max Vines, Associate Biochemist, Citrus Station, Sept. 1, 1960 William Fred Chapman, Jr., Asst. in Ag. Economics, Ag. Econ. Dept., Sept. 15, 1960, USDA George J. Fritz, Asst. Plant Physiologist, Botany Dept., Oct. 1, 1960 Gerald Rogers Davis, Asst. Meteorologist, Weather Forecasting Service, Oct. 1, 1960 John Alan Mortensen, Asst. Geneticist, Watermelon and Grape Lab., Oct. 1, 1960 T. W. Casselman, Asst. Ag. Engineer, Everglades Station, Nov. 1, 1960 Robert Franklin Brooks, Asst. Entomologist, Citrus Station, Nov. 1, 1960 Alan Beverly Irving, Int. Asst. in Ag. Econ., Ag. Econ. Dept., Nov. 8, 1960 Warren Reuben Wallis, Asst. Meteorologist, Weather Forecasting Service, Nov. 21, 1960 Robert D. Blackburn, Asst. Agronomist, Everglades Station, Dec. 1, 1960, USDA Lyle W. Weldon, Asst. Agronomist, Everglades Station, Dec. 1, 1960, USDA Richard Franklin Stouffer, Asst. Virologist, Plant Pathology Dept., Jan. 1, 1961 Charles Howard Curren, Entomologist, Watermelon and Grape Lab., Jan. 16, 1961 Robert Harold O'Bannon, Int. Asst. in Ani. Husbandry, An. Sci. Dept., Feb. 1, 1961 Ralph Ray Smalley, Research Associate, Everglades Station, Feb. 1, 1961 Roy Glendon Stout, Asst. Ag. Economist, Ag. Econ. Dept., Feb. 1, 1961 Gilbert Eugene Alberding, Assistant in Chemistry, Citrus Station, April 1, 1961 Robert Crossly Bullock, Associate Entomologist, Citrus Station, April 1, 1961 William P. Coulter, Asst. Editor, Editorial Dept., April 1, 1961 Raymond Robert Hancock, Ag. Statistician, Ag. Econ. Dept., April 1, 1961, USDA Leo Daniel Marquis, Jr., Asst. Ag. Statistician, Ag. Econ. Dept., April 1, 1961, USDA Harry Gene Witt, Asst. Ag. Statistician, Ag. Econ., April 1, 1961, USDA Albert Benjamin Krienke, Int. Asst. in Ag. Economics, Ag. Econ. Dept., May 1, 1961 Margarete Gertrude Goerigk, Asst. in Bacteriology, Veterinary Sci. Dept., May 15, 1961 Elmer George Close, Int. Asst. in Ag. Economics, Ag. Econ. Dept., June 1, 1961 Promotions George Lafayette Capel, Associate Agricultural Economist, Agr. Econ. Dept., July 1, 1960 William Grant Mitchell, Associate Editor, Editorial Dept., July 1, 1960 Julian Mostella Myers, Agricultural Engineer, Agr. Eng. Dept., July 1, 1960 William Freeman Newhall, Associate Biochemist, Citrus Station, July 1, 1960 Ralph H. Sharpe, Horticulturist, Fruit Crops, July 1, 1960 Kenneth Roberts Swinford, Forester, Forestry Dept., July 1, 1960 Florida Agricultural Experiment Stations Buford Dale Thompson, Associate Horticulturist, Vegetable Crops Dept., July 1, 1960 Sik Vung Ting, Associate Biochemist, Citrus Station, July 1, 1960 James Marvin Wing, Associate Dairy Husbandman, Dairy Science Dept., July 1, 1960 Philip John Westgate, Horticulturist, Central Florida Station, July 1, 1960 Billie S. Lloyd, Assistant in Agricultural Economics, Agr. Econ. Dept., Nov. 1, 1960 Transfers Lawrence Adkins Reuss, from Costa Rica Assignment to Ag. Economics Dept., July 1, 1960 A. E. Kretschmer, Jr., from Costa Rica Assignment to Everglades Ex- periment Station, Aug. 24, 1960 W. G. Blue, from Costa Rica Assignment to Soils Department, Sept. 16, 1960 Resignations Robert E. Hellwig, Asst. Engineer, Everglades Station, July 1, 1960, USDA Paul A. Mott, Asst. Meteorologist, Weather Forecasting Service, July 1, 1960 Clyas Lee Crenshaw, Asst. Economist, Ag. Econ. Dept., July 31, 1960 D. C. Russell, Associate Meteorologist, Weather Forecasting Service, Aug. 1, 1960 R. G. Orellana, Associate Plant Pathologist, Plant Pathology Dept., Aug. 16, 1960, USDA John Ralph King, Associate Entomologist, Citrus Station, Aug. 31, 1960 Chi-Wu Wang, Associate Forester, Forestry Dept., Aug. 31, 1960 Stanley A. Ostazeski, Asst. Plant Pathologist, Plant Path. Dept., Sept. 1, 1960, USDA Louis Vernon Dixon, Asst. Ag. Economist, Ag. Econ. Dept., Sept. 2, 1960, USDA Shurley Allen Poole, Int. Asst. in Ag. Economics, Ag. Econ. Dept., Sept. 15, 1960 Howard J. Teas, Associate Biochemist, Botany Dept., Sept. 16, 1960 Thomas Everett Pope, Asst. Horticulturist, Orn. Hort. Dept., Sept. 29, 1960 Ronald John Drago, Asst. in Agronomy, Agronomy Dept., Oct. 14, 1960 Levi Allen Powell Sr., Asst. Ag. Economist, Ag. Econ. Dept., Nov. 30, 1960 William Grierson, Associate Chemist, Citrus Station, Jan. 31, 1961 John T. McCall, Asst. Chemist, Animal Science Dept., Feb. 28, 1961 Edward John Deszyck, Associate Horticulturist, Citrus Station, Feb. 28, 1961 Pierre Jean Jutras, Asst. Ag. Engineer, Citrus Station, Feb. 28, 1961 William J. Brown, Asst. Editor, Editorial Dept., Feb. 28, 1961 Jane Beck Walker, Asst. Bacteriologist, Vet. Sci. Dept., Mar. 17, 1961 Donald Washburn Clancy, Entomologist, Citrus Station, Apr. 30, 1961 D. B. Linden, Asst. Agronomist, Agronomy Dept., May 31, 1961 Herbert Winthrop Warburton, Asst. in Ag. Economics, Ag. Econ. Dept., June 20, 1961 William Roy Pritchard, Veterinarian and Head, Vet. Sci. Dept., June 30, 1961 Frank Thomas Hady, Ag. Economist, Ag. Econ. Dept., June 30, 1961, USDA L. E. Hughes, Associate Meteorologist, Weather Forecasting Service, June 30, 1961 Annual Report, 1961 Retirements, 1960-61 J. Francis Cooper, Editor and Head, Editorial Dept., April 30, 1961 Mark W. Emmel, Veterinarian, Vet. Sci. Dept., June 30, 1961 Homer E. Bratley, Assistant Entomologist, Entomology Dept., June 30, 1961 Retirements Prior to 1960-61 (Emeritus) Arthur Liston Shealy, Animal Husbandman and Head, Ani. Sci. Dept., 1949 Gulie Hargrove Blackmon, Horticulturist, Orn. Hort. Dept., 1954 Levi Otto Gratz, Assistant Director, 1954 William Burleigh Tisdale, Plant Pathologist and Head, Plant Path. Dept., 1955 Arthur Forrest Camp, Vice-Director in Charge, Citrus Station, 1956 Oudia Davis Abbott, Home Economist, Food Tech. and Nutr. Dept., 1958 Lillian E. Arnold, Associate Botanist, Plant Path. Dept., 1958 Thomas Bregger, Plant Physiologist, Everglades Station, 1958 P. T. Dix Arnold, Associate Dairy Husbandman, Dairy Dept., 1959 Rudolf William Ruprecht, Chemist and Vic-Director, Central Fla. Station, 1959 Jesse Roy Christie, Nematologist, Entomology Dept., 1960 GRANTS AND GIFTS Commercial Grants and Gifts accepted as support for existing pro- grams during the year ending June 30, 1961. Financial assistance is here- by gratefully acknowledged. Abbott Laboratories, North Chicago, Illinois Poultry Science Department $2,000 American Agricultural Chemicals Company, New York 7, New York Soils Department $3,600 Citrus Experiment Station $900 American Cyanamid Company, New York 20, New York Animal Science Department $2,500 Food Technology Department $1,500 Citrus Experiment Station $900 Sub-Tropical Experiment Station $500 American Dehydrators Association, Kansas City 5, Missouri Animal Science Department $2,500 American Smelting and Refining Company, South Plainfield, New Jersey Everglades Experiment Station $500 Atlantic Creosoting Corporation, Portsmouth, Virginia Forestry Department $600 Brunswick Pulp and Paper Company, St. Simons Island, Georgia Forestry Department $2,000 Buckeye Cellulose Corporation, Foley, Florida Forestry Department $2,000 California Chemical Company, Orlando, Florida Plant Pathology $500 California Spray Chemical Corporation, Richmond, California Everglades Experiment Station $1,000 Citrus Processors Association, Winter Haven, Florida Animal Science Department $6,000 Commercial Solvents, New York 16, New York Animal Science Department $1,200 Florida Agricultural Experiment Stations Container Corporation of America, Fernandina Beach, Florida Forestry Department $2,000 Continental Can Company, Chicago 20, Illinois Citrus Experiment Station $3,500 Continental Can Company, Inc., Savannah, Georgia Forestry Department $2,000 Cornellis Seed Company, St. Louis 2, Missouri Vegetable Crops $250 Dixie Lily Milling Company, Williston, Florida Animal Science $20,400 The DOW Chemical Company, Winter Park, Florida Citrus Experiment Station $500 E. I. du Pont de Nemours and Company, Wilmington, Delaware Everglades Experiment Station $750 Everglades Experiment Station $500 Sub-Tropical Experiment Station $1,000 Eppinger and Russell Company, Jacksonville, Florida Forestry Department $600 Ferro Corporation, Cleveland 5, Ohio Soils Department $2,500 Ferry Morse Seed Company, Mountain View, California Vegetable Crops $250 Florida Agricultural Research Institute, Winter Haven, Florida Citrus Experiment Station $3,600 Florida Flower Association, Bradenton, Florida Sub-Tropical Experiment Station $1,000 Florida and Georgia Cigar Leaf Tobacco Association, Quincy, Florida North Florida Experiment Station $10,000 F. Julius Fohs, Houston 2, Texas Ornamental Horticulture Department $1,000 Food Machinery and Chemical Corporation, Lakeland, Florida Fruit Crops Department $2,500 Fort Dodge Laboratories, Fort Dodge, Iowa Veterinary Science Department $2,000 Geigy Agricultural Chemicals, Yonkers, New York Agronomy Department $500 Botany Department $2,000 Everglades Experiment Station $500 Sub-Tropical Experiment Station $500 General Chemical Division, Orlando, Florida Citrus Experiment Station $500 Sub-Tropical Experiment Station $200 General Chemical Division, Morristown, New Jersey Citrus Experiment Station $500 The Golf Course Superintendents of America, Scholarship and Research Fund, Jacksonville, Florida Ornamental Horticulture Department $500 W. R. Grace and Company, Clarksville, Maryland Everglades Experiment Station $2,000 Growers Administrative Committee, Lakeland, Florida Agricultural Economics Department $3,700 Highland Bentgrass Commission, Corvallis, Oregon Ornamental Horticulture Department $1,000 Hillsborough County Commissioners, Tampa 1, Florida Citrus Experiment Station $2,850 Annual Report, 1961 Hollingsworth and Whitney, Mobile, Alabama Forestry Department $2,000 International Minerals and Chemical Corporation, Skokie, Illinois Fruit Crops Department $5,000 International Paper Company, Mobile, Alabama Forestry Department $2,000 Jensen-Salsbery Laboratories, Inc., Skokie Illinois Veterinary Science Department $3,000 Lake Garfield Nurseries, Bartow, Florida Citrus Experiment Station $3,000 Eli Lilly Company, Indianapolis 6, Indiana Plant Pathology Department $500 Lilly Research Laboratories, Eli Lilly Company, Indianapolis 6, Indiana Gulf Coast Experiment Station $1,100 Martin County Flower Growers Association, Stuart, Florida Sub-Tropical Experiment Station $1,000 Olin Mathieson Chemical Corporation, Port Jefferson Station, New York Everglades Experiment Station $500 Sub-Tropical Experiment Station $800 Merck and Company, Rahway, New Jersey Animal Science Department $2,000 Moorman Manufacturing Company, Quincy, Illinois Animal Science Department $3,000 Everglades Experiment Station $2,500 Monsanto Chemical Company, St. Louis, Missouri Poultry Science Department $4,000 Everglades Experiment Station $1,000 National Association of Artificial Breeders, Columbia, Missouri Dairy Science Department $1,200 Niagara Chemicals, Jackson, Mississippi Citrus Experiment Station $500 Pabst Brewing Company, Milwaukee, Wisconsin Everglades Experiment Station $5,000 Chas. Pfizer and Company, Inc., Terre Haute, Indiana Animal Science $1,000 Poultry Science Department $1,000 Polk County Commissioners, Bartow, Florida Citrus Experiment Station $2,850 Rayonier, Inc., Fernandina Beach, Florida Forestry Department $2,000 Rohm and Haas, Philadelphia, Pennsylvania Citrus Experiment Station $3,000 Sub-Tropical Experiment Station $1,500 Scott Paper Company, Mobile, Alabama Forestry Department $2,000 Seaboard Air Line Railroad Company, Richmond, Virginia Forestry Department $600 Shell Chemical Company, New York 20, New York Food Technology Department $3,000 Shell Chemical Company, Atlanta, Georgia Central Florida Experiment Station $600 Shell Development Company, Modesta, California Plant Pathology $600 Central Florida Experiment Station $800 Everglades Experiment Station $500 Florida Agricultural Experiment Stations Smith-Douglass Company, Inc., Norfolk, Virginia Poultry Science Department $3,000 Soft Phosphate Research Institute, Ocala, Florida Animal Science Department $4,000 Southern Wood Preserving Company, Atlanta, Georgia Forestry Department $600 Squibb Institute, New Brunswick, New Jersey Animal Science Department $1,800 Stauffer Chemicals Company, Mountain View, California Citrus Experiment Station $1,500 St. Regis Paper Company, Jacksonville, Florida Forestry Department $2,000 Tennessee Coal and Iron, Fairfield, Alabama Citrus Experiment Station $1,200 Tennessee Corporation, Atlanta, Georgia Citrus Experiment Station $1,000 Tennessee Corporation, College Park, Georgia Central Florida Experiment Station $500 Central Florida Experiment Station $500 Union Bag-Camp Paper Corporation, Savannah, Georgia Forestry Department $2,000 United States Sugar Corporation, Clewiston, Florida Everglades Experiment Station $2,000 Grants for Basic Research were accepted from National Agencies as follows: The Atomic Energy Commission, Oak Ridge, Tennessee Agronomy Department $15,800 Agronomy Department $9,500 Botany Department $4,000 Botany Department $12,490 Soils Department $11,692 National Institutes of Health, Bethesda, Maryland Animal Science Department $10,005 Animal Science Department $17,250. Animal Science Department $30,475 Food Technology Department $12,982 Food Technology Department $21,077 Food Technology Department $6,825 Plant Pathology Department $14,892 Veterinary Science Department $17,928 Veterinary Science Department $19,931 Veterinary Science Department $12,896 The National Science Foundation, Washington, D.C. Agronomy and Plant Pathology $6,100 REPO SUMMA Salaries & W ages ..-............-.... ...-.... Travel ........ ......-... Transportation & Communication ..... Utilities ........ ... ... .....- ..... . Rentals .......... .... ........... Printing ..-..---......- ----. ----------- Repairs & Maintenance .................. Contractual Services .........-.....-... .... Supplies & Materials .......................... Equipment .....-........ ---. ... .. Land & Buildings ................. ...... Total Expenditures ................. . RT OF THE ADMINISTRATIVE MANAGER RY OF EXPENDITURES OF FEDERAL FUNDS 1960-61 SHatch Funds RRF AMA $310,631.83 5,630.88 453.07 2,510.11 48.90 17.45 4,754.56 2,586.83 41,214.63 26,582.59 28,639.69 $423,070.54 $ 38,823.15 4,802.54 334.98 143.91 13.71 535.35 311.44 8,972.56 6,391.61 643.93 $ 60,973.18 $ 11,000.00 $ 11,000.00 Grand Total Federal Funds $360,454.98 10,433.42 788.05 2,654.02 48.90 31.16 5,289.91 2,898.27 50,187.19 32,974.20 29,283.62 $495,043.72 SUMMARY OF EXPENDITURES OF STATE FUNDS 1960-61 Salaries & Wages ......... Travel ....--..... ............ ..... Transportation & Communication ............ Utilities ........ .......... Rentals ......................... ...- Printing ....................... Repairs & Maintenance.. Contractual Services .... Supplies & Materials ... Equipment ..................... Land & Buildings ........... Plant Funds ................... Transfers ................... Total .............. .. .... .... Fla. Agri. Experiment Sta. General Revenue Funds $3,619,536.90 129,776.76 48,038.56 72,353.07 24,356.84 45,648.83 49,507.50 31,305.97 348,949.77 119,965.76 36,099.38 20,980.84 $4,546,520.18 Special Citrus Crop Estimate Research Fund $ 41,134.25 19,979.08 561.90 82.50 1,883.94 311.95 8,670.15 $ 72,623.77 S Fou Pr I $6 1 special nation Seed ogram Fund ,960.00 ,100.65 231.11 16.38 17.98 664.76 Incidental Funds $ 61,272.81 4,534.74 3,749.92 9,099.60 16,615.72 7,759.56 17,867.77 19,879.03 313,582.68 41,551.01 40,775.04 1,850.00 $8,990.88 $538,537.88 Grants and Donations Funds $170,453.12 20,137.98 2,260.87 2,475.92 29.20 8,659.73 3,281.13 3,069.99 60,093.47 63,687.99 30,474.60 $364,624.00 Total State Funds $3,899,357.08 175,529.21 54,842.36 83,928.59 41,001.76 62,084.50 70,756.88 56,138.93 723,602.63 233,874.91 107,349.02 20,980.84 1,850.00 $5,531,296.71 Annual Report, 1961 AGRICULTURAL ECONOMICS During the year, work was completed on 7 projects, and work was be- gun on 5 new projects. At the close of the fiscal period, research was being conducted on 45 projects. During the year there were 6 resignations and 7 appointments. FARMERS' COOPERATIVE ASSOCIATIONS IN FLORIDA State Project 154 H. G. Hamilton, A. H. Spurlock and M. D. Love, Jr. From 1885 to 1959 there were issued 927 charters to farmer cooperative associations. In 1959 there were 159 cooperatives operating. These cooper- atives marketed 38 percent of the Florida citrus crop, 38 percent of the milk, 20 percent of the truck crops and 12 percent of the cattle. Members' equity in the cattle associations averaged $442 per member, $7,236 for the truck crop associations, $5,723 for citrus packing associations, $29,274 for citrus processing associations and $51,616 for dairy distributing asso- ciations. Financial ratios indicate that most Florida cooperatives operat- ing in 1959 were in sound financial condition. However, there was a great variation in the volume of business handled and the cost of opera- tions. The size of business of 27 citrus packing associations ranged from an index of 19 to 266 when the average of all associations is taken as 100. Cost of packing fresh citrus fruit ranged from an index of 77 to 133 when the average of all associations is taken as 100. Most of the failures of Florida cooperatives have been due to technological advancement and changes in market structure. However, many failures have been due to size of business, unequal treatment of members, extent that facilities were used at full capacity and investment in facilities per unit of ca- pacity. FACTORS AFFECTING COSTS AND RETURNS IN FLORIDA CITRUS PRODUCTION Hatch Project 186 Zach Savage There are many factors that influence yields of citrus fruit. Some of these factors cannot be controlled, some can be partially controlled and others can be largely controlled. Inherent factors of the variety and kind of citrus influence tendencies for high or low yields. Some varieties and kinds tend to bear more heavily on alternate seasons with intervening seasons of lower yields. Generally, yields following high yielding seasons tend to be lower. Health and vigor of the tree materially affect yield. Adequacy and proper ratio to each other of the necessary fertilizer el- ements present tend toward high yields. Insect and disease control, tem- perature and soil moisture are very important factors in maintaining high yields. Maintaining a large number of favorable production factors tends toward continuous high yields. However, it frequently happens that for various reasons not all of which can be accounted for adequately - yields are low during some seasons. At times, yields are extremely low. These variations make it hard to arrive at representative yield figures for the various kinds of citrus. Florida Agricultural Experiment Stations Average or usual yields are sometimes used in indicating what may be expected in yields over a period of time. However, such data do not indicate what may be expected in variations from the average yield of a particular grove or between yields of different groves. A publication was issued that includes an average or normal yield generally expected by age of tree for early, midseason and late oranges, seedy and seedless grapefruit, tangerines and temple oranges. Usual variations are indi- cated by a "high" and "low" figure for each age. These data include the 10 seasons of 1947-57. FACTORS AFFECTING BREEDING EFFICIENCY, ITS POSSIBLE INHERITANCE AND DEPRECIATION IN FLORIDA DAIRY HERDS State Project 345 A. H. Spurlock Records of replacements, causes of losses and disposal dates were continued on 5 dairy herds. Data were combined with results previously obtained to determine length of life, depreciation rates and reasons for replacements. The life span of 3,502 replaced cows averaged 6.5 years, or about 4.5 years in the milking herd. The disposal rate increased rapidly after the first year in the herd, and after 3 years less than two-thirds of the original animals remained. After 5 years, 61 percent were gone. Cows reaching age 6 had a life expectancy of 2.8 years and averaged 8.8 years of life; cows reaching age 10 had 1.7 years life expectancy and averaged 11.7 years of life. Live disposals from the herd were principally for low production (30.6 percent), mastitis or some form of udder trouble (24.2 percent) and reproductive trouble (18.0 percent). These 3 reasons or combinations of them were responsible for 76 percent of the live disposals. About 10 per- cent of the live disposals were for unstated reasons. Death from all causes accounted for 14.1 percent of all disposals. (See also Project 345, Dairy Science Department.) CROP AND LIVESTOCK ESTIMATING ON FLORIDA FARMS WITH EMPHASIS ON VEGETABLE CROPS State Project 451 G. N. Rose, G. G. Goshorn and R. R. Hancock1 This project is conducted in cooperation with and under the direction of Statistical Reporting Service, Field Operations Division (formerly Agri- cultural Estimates Division, Agricultural Marketing Service). An ex- panded program on celery statistics was added to the current estimates of acreage, yield, production and prices of Florida's vegetable crops. The work was tied in with the regular national monthly reports of acreage intentions, preliminary acreage, forecasts of production and fi- nal production and utilization. These estimates were made for 4 fall, 14 winter and 11 spring vegetable crops and included both fresh market and processing utilization. The tomato crop received special weekly treatment - a detailed report of which is covered under Project 822. The compre- hensive weekly summary, "Florida Weekly Weather and Crop Bulletin," was continued in addition to monthly production forecasts for Florida and competing states. An extensive post-season interview survey under way at the beginning of the fiscal year was completed. This survey furnished data for the dis- 1 Cooperative with Statistical Reporting Service, USDA. Annual Report, 1961 tribution of acreage and production by marketing areas and counties. Survey results formed the basis for the current data published in "Flor- ida Vegetable Crops, Annual Statistical Summary," Volume XVI, 1960 - 1,500 copies. MARKETING MEAT ANIMALS IN FLORIDA Hatch Project 602 W. K. McPherson (Regional SM-7) Tabulation of data to be used in comparing prices in several mar- kets was continued. The results of the entire study were summarized and the project terminated. Some of the work initiated under this project will be continued under a new project. PASTURE PROGRAMS AND BREEDING SYSTEMS FOR BEEF PRODUCTION ON FLATWOODS SOILS OF CENTRAL AND NORTH CENTRAL FLORIDA State Project 627 R. E. L. Greene This experiment is designed to evaluate pasture programs varying in intensities of fertilization and levels of management in terms of forage production, soil nutrient balance and rate of economy of beef production. The Agricultural Economics Department has the responsibility for com- paring costs and returns for each program to show how well it pays. To make the results applicable to commercial operations, the experimental data are supplemented with cost data from other sources. Summaries were made showing costs and returns for the 1958-59 and 1959-60 seasons. In each year, Program 2 had the lowest net cost per pound of beef and the highest net returns per acre. This was a clover- grass program receiving the lowest application of fertilizer per acre and no top dressing. Production of beef on this program averaged 235 pounds per acre in 1958-59 and 316 pounds in 1959-60. In the 1958-59 season, production of beef on the all-grass program was 37 pounds more than on Program 2; in the 1959-60 season it was 31 pounds less. In each season, the net cost per pound of beef on the grass program was about double that on Program 2. The difference was due mainly to the much higher fertilizer cost and also the necessity to feed more supplemental feeds. ECONOMY OF MARKETING AND METHODS OF HANDLING SWEET CORN FOR LONG DISTANCE SHIPMENTS Regional Project 630 A. H. Spurlock (Regional SM-8) The economic phase of this project has been inactive during the past year except for completion of a manuscript covering results of the study. The manuscript has been approved by the Publications Committee. (See also Project 630, Food Technology and Nutrition Department.) IMPROVING METHODS AND PRACTICES IN HARVESTING, HANDLING AND PACKING EARLY IRISH POTATOES State Project 638 R. E. L. Greene and G. L. Capel2 Work has been devoted to completing the analysis of the data col- lected on a study of potato packinghouses in Florida and Alabama. A 2 Marketing Economics Division, Economic Research Service, USDA. Florida Agricultural Experiment Stations mimeographed report was published on "Cost of Alternative Methods of Bagging and Loading Potatoes in the Southeast." Two methods of filling and weighing bags were studied. In the older method, bags were filled and set off to be weighed as a separate oper- ation. In the newer method, workers fill the bags and simultaneously weigh them on scales built into the filling stations. For both burlap and paper bags, the new method has lower costs at annual volume levels at which most packinghouses operate (above 25,000 hundredweights for firms packing in burlap and 24,000 hundredweights for firms packing 50-pound paper bags). Packed bags can be handled in at least 3 ways on 2-wheel hand trucks, conveyors and fork trucks. This analysis indicated that in most situations costs are lower for the hand truck method. An important ex- ception is for a house loading motor trucks only the conveyor method has lower costs at average to high annual volume levels. When both trucks and rail cars are to be loaded, the hand truck method has the lowest costs, except at the highest volume levels used in this study. Under the conditions that the packinghouses studied operated, the fork trucks had costs higher than either of the other 2 methods. This project will be closed with the preparation of a final manuscript during the coming year. LEGAL ASPECTS OF FARM TENANCY IN FLORIDA Hatch Project 656 J. R. Greenman and H. G. Hamilton Revision of a manuscript entitled "Inheritance Laws Affecting Florida Farms and Farm Families" has been continued. Additional preliminary work on a study of administrative arrangements and laws for the control and use of water in Florida has been done. Since the original objectives of this project had been accomplished, it was terminated as of June 30, 1961; and the work on inheritance laws and the control and use of water will be conducted under a new project entitled "Economic, Legal and Administrative Aspects of Water Use and Control for Agriculture of Flor- ida." It is believed that publications based upon this research should be useful to farmers and those working with farmers in providing a better understanding of the laws dealing with the vital problems of inheritance and the economic, legal and administrative problems connected with the control and use of water. EFFECT OF DIFFERENT FORMS OF NITROGENOUS FERTILIZERS ON THE YIELD AND QUALITY OF VEGETABLES State Project 660 D. L. Brooke An economic evaluation was made of the experimental results from field trials of the effect of 5 different sources of nitrogen in fertilizer materials on the yield of cucumbers and pole beans in the spring of 1960. Differential price maps indicate that at a farm price of $0.50 or more per bushel for cucumbers, farmers would profit by using calcium nitrate rather than sodium nitrate if the cost of the former was not more than $0.03 per pound of nitrogen higher than the cost of sodium nitrate. If the farm price was $3.00 or more per bushel, farmers would benefit by using the calcium nitrate source as long as its cost was not more than $0.18 per pound higher than sodium nitrate. Ammonium nitrate is also a profitable substitute for sodium nitrate at a very low farm price per bushel of cucumbers. Similar comparisons for pole beans indicate that ammonium sulfate and calcium nitrate produce the most profitable Annual Report, 1961 yields within the normal range of prices for the crop and differentials in cost over other sources of nitrogen. On a net return per acre per pound of nitrogen applied basis, the ammonium nitrate source of nitrogen was most profitable and the so- dium nitrate source least profitable for both cucumbers and pole beans. (See also Project 660, Gulf Coast Experiment Station.) MARKETING PRACTICES OF FLORIDA FLOWER AND ORNAMENTAL PLANT GROWERS State Project 679 C. N. Smith, D. L. Brooke and H. G. Hamilton The manuscript on marketing ferns was revised. Additional informa- tion on industry trends was obtained in a series of field interviews. Work was begun on a manuscript, prepared in cooperation with per- sonnel at the Gulf Coast Station, relating to the gladiolus industry. METHODS OF ESTIMATING FLORIDA CITRUS PRODUCTION State Project 685 J. C. Townsend, Jr.", P. E. Shuler' and R. G. Stout Frame and limb fruit counts for the preseason citrus estimates were completed in early September. Shortly after this completion Hurricane Donna did considerable damage to the crop; consequently, a resurvey was conducted which estimated the storm damage at about a 10 percent loss of crop. October estimates based on the fruit count, projected sizes and drop rates were 90.5 million boxes of oranges and 30 million boxes of grapefruit. Final estimates are going to be close 87.0 million boxes of oranges and 31.8 million boxes of grapefruit. A manuscript entitled "Size of Fruit and Droppage Rates Influence Total Citrus Production" was prepared for review for publication. New work was initiated in September 1960 to collect data on internal fruit quality. A new type frame count was devised to estimate the number of fruit on each tree. This procedure was tested during May and June on 115 Valencia trees. Tree height and diameter measurements were obtained, and an estimate of the bearing surface was determined. Fruit per frame was determined for several frame readings on each tree. These readings were expanded to a tree total by multiplying by the reciprocal of the ratio of the area of the frame to the bearing surface area. The estimate for the 115 trees was 69,269 fruit, and the actual number was 68,658, giving an error of 0.9 percent. It is planned to utilize this procedure during the coming year to estimate temple and tangerine production, since these trees are too thorny to make a limb count. EXPANDING THE MARKET FOR FLORIDA FLORICULTURAL AND ORNAMENTAL HORTICULTURAL CROPS Regional Research Project 700 C. N. Smith and D. L. Brooke (Regional SM-12) Further modifications were made on the pilot model of the display cart developed for displaying cut flowers in supermarkets. Constructed of plywood, the cart is 31 inches high and measures 18x30 inches at 3Cooperative with Statiscal Reporting Service, USDA. Florida Agricultural Experiment Stations the top. The sides and ends taper to a bottom measurement of 131x30 inches. A pan 8 inches deep, with cells to hold flower stems in place, is set in the top of the cart. Water is placed in the pan and can be drained through a rubber spout. The cart was tested in several stores and met with favorable ac- ceptance from grocery shoppers as well as store personnel. A manuscript on handling cut flowers in mass market stores was prepared. (See also Project 700, Ornamental Horticulture Department.) This project was closed June 30, 1961. ECONOMICS OF FLORIDA DAIRY FARMING State Project 701 R. E. L. Greene Work in cooperation with the Florida Milk Commission to collect data on the cost of producing milk in each of the 3 areas under its supervision was continued. Preliminary tabulation and analysis of data for 51 farms in the Tampa Bay milk marketing area for the 1959 calendar year were completed. A preliminary mimeographed report was issued. In the spring of 1961, the Milk Commission requested a resurvey of a part of the farms included in the central Florida study for 1958. Rec- ords have been obtained for 20 of the 34 farms in the original study. These data are now in the process of being summarized. On a 4 percent fat-corrected milk basis, the net cost per gallon of producing milk in 1959 on all farms in the Tampa Bay area was 60.17 cents. This compared to an average cost of 55.93 cents per gallon in northeast Florida and 60.50 cents in central Florida in 1958. It is felt that the level of cost was about the same in the 2 years. It is believed the data for the 2 years are comparable. In each area, the net cost per gallon was substantially lower on large farms as compared to small farms. The highest net returns per gallon were on large farms in cen- tral Florida. Even though producers in northeast Florida had a lower cost than those in the other 2 areas, their percent of production in other than class 1 milk was such that the net returns per gallon were about the same in the 3 areas. CENSUS OF CITRUS GROVES IN FLORIDA State Project 720 J. C. Townsend, Jr.,' R. G. Stout and J. W. Todd' After several years preliminary ground work, a joint undertaking on the part of the U.S. Department of Agriculture (Statistical Reporting Service) and the Florida Department of Agriculture (Division of Plant Industry) was started August 1, 1960, to determine changes that have taken place in the citrus industry since the 1957 census. The new cen- sus is set up on a 5-year plan. Twenty percent of all land sections con- taining old citrus as well as new and outlying areas are being checked for new plantings each year. For a rate of change in old groves, a sample of groves within this area is being completely re-enumerated. From this, changes that have taken place during the 5-year period since the last census will be determined. First year results are now being proc- essed, and results are expected to be released shortly. The Statistical Reporting Service is responsible for over-all supervi- sion of all statistical and tabulating work, and the Division of Plant Industry provides the five 2-man crews to do the grove inspection. Cooperative with Statistical Reporting Service, USD'A. Annual Report, 1961 AN ECONOMIC EVALUATION OF GRADE AND SIZE STANDARDS FOR FLORIDA TOMATOES State Project 787 M. R. Godwin and W. T. Manley' In the spring of 1960, marketing tests were conducted in 11 large supermarkets in the Dayton, Ohio, market area to examine the prefer- ence patterns of consumers for Florida mature green tomatoes. The ex- periments were designed to determine the importance which consumers attach to varying grade and size characteristics. The purpose of the research is to provide information which will aid in efficient price determination and effect economies in operational procedures in the dis- tribution process. Test situations were arranged so that the preference pattern could be examined for 3 grades and 11 sizes of tomatoes. From the tests it is possible to analyze the effect of grade upon the sales of tomatoes, the effect of size on sales and the combined effect of both grade and size upon consumer purchases. The results of a preliminary analysis of the data were published in the 1960 Proceedings of the Florida State Horticultural Society, October 1960. This article appears as Florida Agricultural Experiment Stations Journal Series No. 1178. Preliminary results of the marketing tests show that consumers do not discriminate between all current grades and sizes of tomatoes. They did not distinguish between tomatoes that were not greatly different with respect to size or grade, or some combination of size and grade. Grade U. S. No. 1 U. S. No. 2 U. S. No. 3 5x6 6x6 6x7 7x7 7x8 grade and size used as basis for comparison grade-size combinations regarded as equally acceptable grade-size combinations not regarded as equally acceptable Figure 1.-The ability of consumers to discriminate between Florida tomatoes, using the U. S. No. 3 size 5x6 as the basis for comparison. Cooperative with Marketing Economics Division, Economic Research Service, USDA. Florida Agricultural Experiment Stations For example, in a comparison of the sales of the U.S. No. 3 size 5 x 6 tomatoes with the other 10 grade-size combinations tested, consumers found the 5 x 6 U.S. No. 1 tomato superior. However, they regarded the 5 x 6 U.S. No. 3 tomato as equally as good as the 5 x 6 and 6 x 6 sizes of the U.S. No. 2 grade. (See Figure 1.) THE ECONOMIC EFFECT OF PINK TOMATO SHIPMENTS UPON THE FLORIDA TOMATO INDUSTRY State Project 788 M. R. Godwin and W. T. Manley0 During the past several marketing seasons, the practice of shipping vine ripened tomatoes into the terminal markets has gradually increased in importance. This development has created significant changes in the market structure for Florida tomatoes. Inherent in these changes have been certain problems in distribution and marketing. In some cases, new distribution channels have been utilized in the marketing of vine ripened tomatoes. Merchandising methods are in variance to those com- monly used for mature green tomatoes. Tomatoes shipped mature green and vine ripened compete directly with one another in the terminal markets. A survey of the distributive trade was initiated to determine handling practices for vine ripened tomatoes and to examine the adjustments in operational procedures that have been necessary in order for firms to handle and merchandise the product. The survey involved visitations to firms in about 30 terminal market areas. Types of firms visited were tomato repackers, wholesale receivers, commission merchants, and chain store organizations. Most of the field work has been completed. It is anticipated that an analysis of the data will be made and a report on the findings released during the coming year. AN ECONOMIC ANALYSIS OF THE FLORIDA HONEY INDUSTRY Hatch Project 791 H. G. Hamilton and F. J. Hoffer There is a close correlation between Florida citrus production and honey production. From 1939 to 1958 citrus production increased at the rate of 6.8 percent per year and honey increased at the rate of 8.5 per- cent. There are no official grades or container standards for Florida honey. As a result, a multiplicity of grades and containers are used in the industry. This has caused high costs of packing and selling Florida honey. If the industry would adopt standard grades and containers, costs of packing and selling could be greatly reduced, and an effective adver- tising and promotional program could be instituted. During the year a doctoral manuscript based on results of this work was completed by Hoffer. RESPONSE OF FARM INCOME TO CHANGES IN RESOURCE USE ENGENDERED BY ACREAGE CONTROL AND PRICE SUPPORT PROGRAMS State Project 796 L. A Powell, Sr., C. E. Murphree and C. D. Covey A manuscript for publication as a technical bulletin was completed and has been reviewed by the Publications Committee. An examination of the manuscript reviews is in progress. SCooperative with Marketing Economics Division, Economic Research Service, USDA. Annual Report, 1961 CONSUMER USES AND OPINIONS OF FLORIDA LIMES Hatch Project 814 W. T. Manley' and M. R. Godwin This study describes the market status of fresh limes and frozen limeade concentrate at the consumer level and from the standpoint of current distribution and merchandising practices at the retail level. A bulletin entitled "Retail Distribution and Merchandising of Fresh Limes and Frozen Limeade Concentrate" was released in September 1960. It reports the findings of a survey of 258 retail food stores in the Dayton and Cincinnati, Ohio, market areas. The information reveals several im- portant points that may be useful in the formulation of improved mar- keting practices and policies. A bulletin manuscript entitled "Characteristics and Potentialities of the Consumer Market for Florida Limes" received approval for publication in May 1960. It is based on the results of a consumer survey involving personal interviews with 2,172 families in the market area of Dayton, Ohio. An examination of the existing use patterns for fresh limes and froz- en limeade concentrate suggests that these products have a substantial market potential. The fact that a large proportion of consumers do not know about the products or do not use them with any degree of fre- quency suggests that the basic problem of the industry is one of gaining more widespread recognition for its products. The project is closed with this report. THE DEVELOPMENT OF A SYSTEM FOR ESTABLISHING THE SHORT-RUN PRODUCTION OUTLOOK FOR FLORIDA TOMATOES State Project 822 G. N. Rose, G. G. Goshorn and L. D. Marquis' Further expansion in the operational field was made on this project during 1960-61. The objective of the program was to develop the rela- tionship between weekly planting of tomatoes and ultimate weekly pro- duction. Growers and other allied interests were furnished a weekly planting record by areas of the state. This information was integrated with the weekly shipments together with pertinent crop development and conditions. For the first time, the project assumed national scope as the U.S. Department of Agriculture financed the operation of the pro- gram and included Texas in the program. Weekly reports were issued to a mailing list of about 1,000 growers, shippers and others. Publication began the week of September 8 and con- tinued through the spring crop in June. AN APPRAISAL OF THE ECONOMIC CHARACTERISTICS AND PROBLEMS OF LOW INCOME RURAL AREAS IN NORTH AND WEST FLORIDA Hatch Project 826 L. A. Reuss" and R. E. L. Greene Work has been devoted to establishing a basis for measuring the ex- tent of the low income problem and its association with personal limi- tations for employment and limitation on quantities of non-human re- 7 Cooperative with Marketing Economics Division, Economic Research Service, USDA. 8 Cooperative with Statistical Reporting Service, USDA. 9 Cooperative with Farm Economics Division, Economic Research Service, USDA. Florida Agricultural Experiment Stations sources. Previous work indicated that per capital income offered the best measure of the existence of low income problem situations. Advanced age, lack of education and physical disability were taken as criteria of personal limitations on employment and adjustment capabilities. House- hold net worth measured the quantity of capital resources available to the people. Households and individuals having similar capabilities and resources are being studied with relation to some of the possible indications of imperfections in the markets for labor and capital. Specifically, study is being made of differences associated with rurality of the area, mi- gration of youth and sex and color of the individual. Other indications of adjustment potentials being considered include extent of idle cropland on farms and the interest of individuals in enlarging their farms, obtain- ing additional employment and attending adult education classes. COSTS AND EFFICIENCY IN HANDLING FLORIDA CITRUS FRUITS Hatch Project 895 A. H. Spurlock, H. G. Hamilton (Regional SM-22) and G. L. Capel'1 Cost of harvesting fruit for 33 firms, 1959-60, averaged as follows per 1% bushel box: picking oranges, 34.2 cents; picking grapefruit, 25.2 cents; and picking tangerines, 83.6 cents. Hauling from grove to plant cost 11.2 cents a box. Citrus dealers also had an additional cost of 3.3 cents per box for procurement and sale of fruit. Costs of packing and selling Florida fresh cirtus fruit per 1% bushel wirebound box for 39 packinghouses, 1959-60, were $1.08 for oranges and $0.95 for grapefruit. In % bushel fiberboard boxes, costs per equivalent full box were $1.26 for oranges and $1.18 for grapefruit. Average costs for processing, warehousing and selling typical citrus products at 17 plants were as follows: single-strength orange juice in 12/46 cases, sweetened, $1.58; grapefruit sections in 24/303 cases, sweetened, $2.54; frozen orange concentrate in 48/16 cases, unsweetened, selling ex- cluded, $2.20. The work on the evaluation of pallet boxes as containers for handling citrus fruit was continued. A preliminary report was prepared dealing with the physical and economic considerations in using pallet boxes. Compared to handling costs using conventional field boxes, the pallet box method had a cost advantage of 4 to 7 cents per 1% bushel equiva- lent of fruit, depending upon the annual volume. Results of the year's work were distributed to citrus dealers, pack- ers and processors in 3 mimeographed releases for the 1959-60 season: (1) Costs of Picking and Hauling Florida Citrus Fruits, (2) Costs of Packing and Selling Florida Fresh Citrus Fruits and (3) Costs of Proc- essing, Warehousing and Selling Florida Citrus Products. THE IDENTIFICATION AND EVALUATION OF EXTERNAL QUALITY FACTORS IN FLORIDA AVOCADOS HAVING ECONOMIC SIGNIFICANCE TO THE CONSUMER State Project 899 D. L. Brooke, F. W. Williams and W. B. Riggan Analysis of data previously obtained from tests with avocados in 4 supermarkets in Philadelphia, Pennsylvania, has been completed. The tests sought to determine consumer response to price variation, prefer- lc Cooperative with Marketing Economics Division, Economic Research Service, USDA. Annual Report, 1961 ence for avocados having varying amounts of skin scab and scar and preference for avocados having varying degrees of firmness. Results indicate that high-income clientele purchased almost twice as many avo- cados as the low-income clientele. Customers preferred clear fruit almost 2 to 1 over blemished fruit at the same price. At a 4-cent differential in favor of blemished, they bought an equal volume of both. At an 8-cent differential, the ratio of blemished to clear sales was 1.4 to 1, and with a 12-cent differential, 1.8 to 1. Customers preferred soft fruit for immedi- ate consumption rather than hard fruit which must be stored until it is soft. A Ph.D. dissertation entitled "An Evaluation of Consumer Preference and the Effects of Price Variations and Selected Fruit Characteristics on Retail Sales of Florida Avocados" based on this project was accepted by the Graduate School of the University of Florida. A proposed bulletin manuscript on the same subject has been prepared for submission to the Publications Committee of the Experiment Station. A STUDY OF MARKET ORGANIZATION AND PRACTICES FOR POTATOES IN THE HASTINGS AREA OF FLORIDA Hatch Project 916 R. E. L. Greene and Paul T. Blair This project was initiated for the purpose of describing and evaluat- ing recent changes in marketing practices of potato growers and ship- pers and the effects of such changes on the market organization for potatoes in the Hastings area. A survey was made, including 93 growers and 7 selling agencies, to obtain data on significant changes that oc- curred in the Hastings area from 1954 to 1958. During the year, analysis of the data has been completed and a preliminary manuscript prepared. The main problems facing the Hastings potato industry, as seen by growers, were (1) too many potatoes, (2) too many sellers, (3) poor quality, (4) poor market organization and (5) contract growing. To date, no satisfactory solutions have been offered to improve the situ- ation. It appears that group action of some sort on the part of growers and shippers will be necessary. This study attempted to appraise 3 of the more popular approaches-federal marketing agreements and or- ders, central sales agency and grower bargaining associations which have been employed to solve problems similar to those facing growers in the Hastings area. Each proposal was examined from the standpoint of (1) requirements on the part of growers and sellers for successful operation, (2) what it might be expected to accomplish and (3) charac- teristics of the Hastings area which might affect success or failure of the venture. SIMULTANEOUS DETERMINATION OF MULTIPLE DEMANDS FOR CITRUS Hatch Project 937 L. A. Powell, Sr., W. B. Riggan, (Regional SM-22) M. R. Godwin and B. S. Lloyd Information relating to the multiple demand for citrus products would be helpful to the implementation of a coordinated sales program designed to increase industry revenue by improving the utilizational allocation of the citrus crop. Work has been concentrated upon the revision and testing of a tenta- tive model for analyzing the simultaneous demand for frozen orange con- centrate, single-strength juice and fresh oranges at the f.o.b. level in Florida Agricultural Experiment Stations Florida. Modifications or refinements in the form of additional variables included in the formulation during the past year consist of the inclusion of a year effect, the inclusion of a period effect, to adjust for seasonal differences within a year, the development of pseudo-month categori- cal variables to correct for supply effects during periods when fresh oranges were available and during periods when they were not avail- able, and the introduction of quadratic price effects for each of the 3 products under consideration. The results of the work outlined above are all negative. The model fails to explain, with any degree of acceptability, the relationship be- tween the 3 products. The principal manifestation of its shortcoming lies in the inconsistency of the sign of the price coefficients both with- in and between the items included in the analysis. The review and reformulation of the model is nearing completion. Once the model is complete and data for the new variables assembled, appro- priate statistical testing techniques should reveal its acceptability as a suitable estimating device. MARKET STRUCTURE OF THE NURSERY INDUSTRY AMA Project 951 C. N. Smith (ES-606) Field enumeration of data on nursery marketing practices in Pinellas County was completed. An analysis of data from this pilot phase of the project indicated that, of the estimated $1,900,000 in sales of Pinellas County nurserymen, some 95 percent were made at retail. More than 10 percent of all sales by nurserymen were of non-nursery items. Nearly 55 percent of all sales were landscape plantings, and 25 percent were retailed at sales yards. Half of all nursery stock sold consisted of orna- mental plants with 80 percent of these plants in cans. Although large growers catered mainly to retail customers, most sales by small grow- ers were made to the wholesale trade. Experience gained in the pilot phase of the project was utilized in planning a sample survey of the state ornamental nursery industry. A questionnaire was developed, and a stratified sample of 200 growers was selected. Approximately 75 schedules have been taken to date. MARKETING OF FLORIDA CIGAR WRAPPER TOBACCO, TYPE 62 State Project 961 H. B. Clark Interviews with growers indicate that they are pleased with the pres- ent highly integrated system of marketing tobacco. They do not want federal grading or a price support program similar to that being used for other types of tobacco. The production of wrapper tobacco is increasing at a faster rate than consumption. Hence, stocks are increasing, and there is danger of over- production. The costs of growing and marketing are increasing, largely because of increased labor costs. Efforts have been made to economize on labor. Forced sweating in boxes by packers is the primary innova- tion which bears watching. Also, the use of solar heat in barn curing, a practice started in Puerto Rico, is being tried. If any significant progress is made in reducing costs of growing or packing, it must come by lower labor costs. Although it was not possible to get data from enough packinghouses to make a formal analysis, the evidence shows that the grower gets a Annual Report, 1961 35 higher proportion of the selling price of tobacco than he did in the early 1930's. Competition between Connecticut Valley and Florida in producing ci- gar wrapper is keener than ever. The Florida tobacco is inferior in all respects except color. Every effort must be made to improve quality and lower costs to remain in business. LABOR, MATERIALS, COSTS AND RETURNS IN VEGETABLE PRODUCTION State Project 970 D. L. Brooke Data were obtained and summarized, and preliminary tables were prepared on labor and material requirements for 19 different vegetable crops in 15 production areas of Florida. The data indicate the changes in labor requirements as a result of technological advances in produc- tion and harvesting practices. There has been some decrease in man- hour requirements but an increase in tractor hours used in producing and harvesting vegetables. Growers are substituting machines for hand labor and increasing the number of acres of crops produced per man in an attempt to increase production efficiency and reduce costs. ECONOMIC ANALYSIS OF THE MOVEMENT OF HOGS AND PORK IN FLORIDA State Project 973 W. K. McPherson (Regional SM-23) The volume of pork produced, slaughtered and consumed in 4 eco- nomic areas of the state over a period of 3 years was estimated. These data, together with similar data collected in other states, are now being used to determine the nature and extent of inter- and intra-state move- ment of pork and pork products. AN ECONOMIC EVALUATION OF AGRICULTURAL RESOURCES IN FIVE RIVER BASINS OF NORTH AND WEST FLORIDA State Project 974 C. D. Covey and H. G. Hamilton The object of this research was to make projections with respect to agriculture and forestry for the river basins in north and west Florida for the years 1975 and 2000 within a set of certain assumptions. The pro- jection for population in these river basins for 2000 is 1,658,000, or an increase of 116 percent. The number of farms by 2000 is estimated at less than /2 the present number. Cropland is expected to increase by 50 percent. Pasture land is expected to increase slightly and woodland de- crease slightly. Livestock production is expected to be 2 to 3 times as large in 2000 as it was in 1960. This project was closed December 1960. MANAGEMENT AND COST FACTORS RELATED TO MULTIPLE FARROWING Hatch Project 977 W. K. McPherson Researchers participated in the planning of experimental work carried on by the other project leaders. The data collected to date are not yet adequate to make a reliable economic analysis. (See also Project 977, Animal Science Department.) Florida Agricultural Experiment Stations AGE OF HEIFERS AT FIRST BREEDING AS RELATED TO BEEF PRODUCTION State Project 995 R. E. L. Greene The objective of the study is to compare beef production and income from heifers bred first at 1 versus 2 years of age. The Agricultural Eco- nomics Department has the responsibility for assembling data on costs and returns. The project had not progressed far enough at the end of the year for economic comparisons to be made. (See also Project 995, Ani- mal Science Department.) CHANGES IN THE MARKET STRUCTURE FOR SELECTED FLORIDA AGRICULTURAL INDUSTRIES AMA Project 1012 D. L. Brooke, E. G. Close (ES-672) and C. N. Smith Marketing information was obtained by personal interview methods from growers and handlers of watermelons. These data plus information on the factors affecting the price of Florida watermelons have been tab- ulated and are being analyzed. The Florida watermelon market is quite disorganized. It is composed of a great many individualists who question the motives of their competitors and the buyers. Delivered sales (on a shipping-point basis) returned 9 cents per hun- dredweight more to handlers than f.o.b. type sales. Consigned sales returned 49 cents less than f.o.b. and 59 cents per hundredweight less than delivered sales. The principal factors affecting the Florida price appear to be (1) the terminal market supply, which reflects Florida and competing ship- ments, and (2) the average daily temperatures in the terminal markets. Florida shipments alone had little effect on price. IMPROVING METHODS OF HANDLING POTATOES AT THE PACKINGHOUSE State Project 1017 E. K. Bowman," and R. E. L. Greene The proportion of the potato crop in the Hastings area harvested with mechanical equipment continues to increase. A problem in the use of mechanical harvesters that has not been solved satisfactorily is that of providing better methods and facilities at the packinghouse for tempor- ary storage of potatoes hauled in bulk. This is evidenced by the fact that many growers in the area are now buying 2-row harvesters that place the potatoes in bags. Two new methods of handling bulk-harvested potatoes in the Hast- ings area were tested during the year. One was the use of a regular dump-body truck to unload the potatoes into a flat-bottom bin. At the time of washing and grading, the potatoes were moved out of the bin into a flume by means of a stream of water. The second method was to load the potatoes from the harvester directly into large boxes that held about 1,500 pounds. The potatoes were unloaded and handled at the packinghouse by means of a tractor equipped with a fork lift. A box dumper was used to empty the boxes when the potatoes were washed and graded. Samples were collected for each method to compare amount 1 Cooperative with Economic Research Service, Transportation and Facilities Research Division, Marketing Quality Research Division, USDA. Annual Report, 1961 37 of physical damage in the potatoes with that in the regular method of handling. Each of the newer methods was satisfactory from a physical injury standpoint. (See also Project 1017, Agricultural Engineering De- partment.) AN ECONOMIC EVALUATION OF FLUID MILK SUPPLY, MOVEMENT AND UTILIZATION IN FLORIDA Hatch Project 1018 R. E. L. Greene and (Regional SM-10) Herbert W. Warburton The purpose of this study was to determine and analyze fluid milk supply and movement by producing areas, fluid milk utilization patterns and the net balance of supplies and consumption of fluid milk in various market areas. Florida was divided into 5 market areas. Three of the areas corre- spond to the 3 areas under the Florida Milk Commission. The other areas are southeast Florida, which is under a federal marketing order, and northwest Florida, which is under neither federal nor state control. The months of April and October 1959 were selected to show the supply situation, movement and utilization pattern for milk in the state. Data have been collected on the supplies of milk in each market area show- ing volume of producer milk by counties, plus volume and source of out- of-area supplies of milk, including milk from other states. Data have also been collected for individual plants in each area showing processing and distribution facilities, utilization of milk supplies, prices of products and volume of sales by counties. SUPPLEMENTAL FEEDING OF YEARLING STEERS ON PASTURE State Project 1027 R. E. L. Greene The objective of this study is to determine the economic value of several methods of supplemental feeding of grazing yearling steers for 1 year before they are placed in the feed lot and to determine the sub- sequent effects of these methods on feed lot performance. The Agricul- tural Economics Department has the responsibility for making the cal- culations on costs and returns. The experiment has run through 1 cycle. Eighty yearling steers, di- vided into 4 groups, were used to determine the effects of supplemen- tary pasture grazing with a limited amount of concentrate mixture dur- ing various seasons of the year. Some of the animals were then placed in the feed lots for 105 days to measure the results of the different treat- ments on feed lot performance. The data are being summarized to show comparison of net returns for each of the 4 systems of handling yearl- ing steers. (See also Project 1027, Everglades Station.) BLACKSTRAP MOLASSES AND OTHER ENERGY-CONTAINING FEEDS AS A SUPPLEMENT TO PASTURE FOR BEEF COWS State Project 1028 W. K. McPherson Participated in the planning of experimental work carried on by the other project leaders. The data collected to date are not yet adequate to make a reliable economic analysis. (See also Project 1028, Everglades Experiment Station.) Florida Agricultural Experiment Stations A STUDY OF THE IMPACT OF OFF-FARM EMPLOYMENT ON THE USE OF AGRICULTURAL AND HUMAN RESOURCES IN A LOW FARM INCOME AREA OF NORTHWEST FLORIDA" Hatch Project 1030 (Regional S-44) D. E. Alleger In this study the differential effect of economic opportunity was meas- ured by comparisons against state averages for personal incomes, ci- vilian production income, income payments to agriculture and by an in- dex of economic opportunity. In general per capital incomes for Area 1 TABLE 1.-PERCENTAGE DISTRIBUTION OF 205 RURAL FARM FAMILIES, 1955, AND 150 REMAINING, 1960, BY FARM ECONOMIC CLASS, AND BY AREAS 1 AND 2, NORTHWEST FLORIDA. Farm Economic Class I. Rural Residential Nonfarming' .... A. Gainfully employed ...................... B. Retired .............---------......................... C. All others (disabled, etc.) .......... II. Limited Farming .......................... A Part-tim e ..................................... B. Part-retirement ....................3.. III. Low-income Farming ..................... A $50 to $2,499 ............................... B. $2,500 to $4,999 ......................... IV. Commercial Farming ...................... Totals: Percentage .................................. Num ber' 7 .......... ......................... . Percent by Area and by Year Area 1 Area 2 1955 1960 1955 1960 48.5 60.9 41.5 49.4 24.3 29.0 26.4 27.2 12.1 23.2 9.4 17.3 12.1 8.7 5.7 4.9 18.2 11.6 17.0 22.2 13.1 7.3 10.4 9.9 5.1 4.3 6.6 12.3 22.2 11.6 25.4 14.8 14.1 7.3 16.0 4.9 8.1 4.3 9.4 9.9 11.1 15.9 16.1 13.6 100.0 100.0 100.0 100.0 99 69 106 81 1 Value of farm products sold ranging from none to $49. 2 Operator under 65 years of age, working off farm 100 or more days and with sales of farm products ranging from $50 to $2,499. 3 Operator 65 years old or over and with sales of farm products ranging from $50 to $2,499. 4 Operator under 65 years of age, with less than 100 days off-farm work and with sales of farm products ranging from $50 to $2,499. SAll operators with sales of farm products ranging between $2,500 and $4,999. 0 All farm products sold ranged in value from $5,000 upward. 7Differences in numbers between 1955 and 1960 represent either removals by change of residence or deaths of family heads. Note: Individual farm incomes were based on gross estimates made by farmers. 12 Contributing project of the Cooperative Regional Research Project S-44, Southern Region. Annual Report, 1961 remained at around 40 percent of the state average for the last 10 years as compared to 90 percent for Area 2. Proprietor incomes (largely agri- culture) and transfer payments (mostly governmental, such as old age assistance, social security, etc.), are important sources of income for Area 1 (46 percent) and minor sources (16 percent) for Area 2. Manu- facturing accounts for over 27 percent of the civilian production income in Area 2 as compared to less than 6 percent for Area 1. Off-farm mi- gration was toward areas of employment opportunity. The rural families interviewed in this study indicated an aging rural family head and a decreasing reliance upon agriculture for a livelihood. The importance of farms simply as rural homesteads was impressive (Table 1). The proportion of commercial farmers as a percentage of all farms was comparatively small. Between 1955 and 1960 not only were many rural family removals noted, but there were occupational shifts as measured by farm economic reclassifications. These findings stress the need for the people of any given county to secure reasonably satisfac- tory personal incomes if they are to resist the tug of migration. ECONOMIC FACTORS AFFECTING THE FLORIDA CHICK HATCHERY INDUSTRY Hatch Project 1035 R. E. L. Greene and Victor G. Edman The purpose of this project was to describe hatcheries in Florida as to management practices and significant trends, and to determine and analyze major factors affecting costs and returns. At the time of this study there were 33 hatcheries in the state. They ranged in size from 13,300 to 507,000 eggs capacity. Because of the small number and the extreme variation in size, the decision was made not to sample the group but to obtain information from each hatchery. The 33 hatcheries were visited. Data were obtained from 31 firms on management practices. Cost and return data were obtained from 20 hatch- eries. Tabulation and analysis of data are in progress. The average invest- ment of the 20 hatcheries was $28,473 or $162 per 1,000 eggs capacity. The average cost per chick sold was 36.5 cents per egg-type chick and 12 cents for meat-type. Hatching eggs accounted for 47 percent of total costs in egg-type and 67 percent in meat-type. The major factors af- fecting cost per chick were size of hatchery, percent utilization of capa- city, number of chicks sold, cost of hatching eggs and cost of labor. THE EXPORT MARKET POTENTIAL FOR FLORIDA ICEBOX WATERMELONS State Project 1066 M. R. Godwin, B. S. Lloyd and K. M. Gilbraith" The development of a foreign market for the small varieties of Flori- da watermelons could have a big impact on the economic position of both producers and marketing agencies. The purpose of this project is to conduct experimental shipments of Florida icebox watermelons to Eng- land to establish (1) the economic feasibility of such shipments and (2) the degree of consumer acceptance for these melons. During the year, 3 shipments of the New Hampshire Midget and the Sugar Baby varieties of icebox watermelons were made at intervals of 2 weeks. In order to examine the effect of maturity on the acceptability 13 Cooperative with Florida Agricultural Extension Service. Florida Agricultural Experiment Stations of the melons, each of these varieties was shipped at 3 maturity levels - breaker, slightly pink and pink to red. Also, both nailed and wire- bound crates were used in the shipments. Shipments were broken down into variety of melons, maturity stage and type of crates. Ten crates of each possible combination were includ- ed in each of the 3 shipments. The 3 shipments were completed in May 1961, and data are currently being assembled for the analysis. PRELIMINARY NON-PROJECTED STUDIES Florida Agricultural Production Index.-New index numbers measuring the total volume of agricultural production in Florida by groups of com- modities from 1910 to 1960 have been prepared, using a more recent base period, 1947-49. In 1960 the total farm output was 66 percent higher than in the base period, crops were 52 percent higher and livestock products were 109 percent higher. Total farm output in 1960 increased over 1959 by 2.5 percent, though a few individual products, notably meat animals, declined. Tobacco production was 16 percent higher in 1960; oranges, 6 percent; and milk, 5 percent. Since 1940 production of all crops has increased at an average an- nual rate of 4.25 percent, livestock at 5.6 percent and all farm products at 4.7 percent per year. Total production since the base period, 1947-49, was higher because of increased total acreage and number of head of breeding stock, and also because of higher yields or production per unit. Per-unit production in 1960 was 38 percent above the base period for both crops and livestock. (A. H. Spurlock.) Movement of Citrus Trees from Florida Nurseries.-Movement of cit- rus trees from Florida nurseries to Florida destinations was the second highest in number during the 32 years of these records. This season was from July 1, 1959, through June 30, 1960, when there were 2,539,076 trees moved. This movement was 3 percent less than the highest season of 1958-59, 16 percent more than the third highest season of 1956-57 and 220 percent of the 1928-60 average. Eighty percent of the 1959-60 movement was orange trees; 5 percent, grapefruit; 2 percent, tangerine; 7 percent, Murcott Honey; 1 percent, other mandarins; 3 percent, tangelos; and 2 percent limes, lemons and other citrus. Fifty-one percent of the movement was on lemon stock, 31 percent on sour orange, 12 percent on cleopatra mandarin, 4 percent on sweet seedling and 2 percent on other stocks. (Zach Savage.) Competition for Florida Fruit and Vegetable Crops.-The degree of competition which Florida faces is provided by tabulating weekly carlot shipments of selected fruits and vegetables from Florida, other states and foreign countries during the Florida shipping season. Such data are valuable to growers and extension workers in determining the more de- sirable production periods during the Florida season. They are also avail- able to industry groups in the preparation of statistics for hearings on freight rates and marketing agreements and in establishing annual move- ment patterns of Florida crops. Allied service industries may find them valuable in planning peak movement and supply requirements. "Florida Truck Crop Competition. 1. Inter-state and Foreign" was published as Agricultural Economics Mimeo Report 61-3. (D. L. Brooke.) Pecan Production and Marketing in Florida.-The Marketing Econom- ics Research Division of the USDA, ERS, is conducting a study of "Pe- can Marketing in the Southeast." This station cooperated to the extent Annual Report, 1961 41 of securing 100 records on pecan production in 5 counties in Florida. Counties included were Alachua, Jefferson, Jackson, Santa Rosa and Su- wannee. Preliminary results of the survey indicate that (1) 93 percent of the pecan trees on farms are of bearing age; (2) 85 percent of the trees are more than 21 years old and 1/ are older than 41 years; (3) the num- ber of trees planted per acre ranges from 10 in Jackson and Suwannee counties to 17 in Alachua County and averages 13 trees per acre for the 5 counties studied; (4) commercially mixed fertilizers were applied to trees or cover crops on 85 percent of the acreage in pecan orchards, and average application rate was 650 pounds per acre; (5) of the 100 orchards surveyed, 11 were treated for insects, diseases or Spanish moss, and on 90 percent of the acreage treated, the purpose was to control scab; and (7) more than 90 percent of all pecan sales were to regular pecan dealers. (D. L. Brooke.) 42 Florida Agricultural Experiment Stations AGRICULTURAL ENGINEERING Research has been done on 9 regular projects and on preliminary investigations of questions related primarily to efficiencies to be gained by the use of mechanical and physical aids to production. New projects deal with a new system of harvesting and curing tobacco and with equip- ment for removing non-free-flowing feed materials from bulk storage. FERTILIZATION AND CULTURE OF FLUE-CURED TOBACCO Hatch Project 555 J. M. Myers The study of 4 different irrigation management programs for tobacco was continued in 1960. Amount and distribution of rainfall (12.66 inches from March 31 to June 25, 1960) approximated the average for the sea- son of year and location of experiment. The "no delay", "3-day delay", and "6-day delay" plots received 7.24, 5.07 and 2.43 inches of irrigation water in 12, 7 and 4 applications. Treatment responses are shown in Table 1. Highest yield and best quality were obtained from the "no delay" (calculated optimum) irri- gation treatment. Response during the 1960 season is believed to be a more typical response than those received in 1958 or 1959, which were years of exceedingly high rainfall. TABLE 2.-THE EFFECT OF IRRIGATION, IRRESPECTIVE OF NITROGEN OR VA- RIETY TREATMENT, ON THE YIELD AND QUALITY OF TOBACCO, 1960. Irrigation Yield Price Value I Lbs./A. I /Lb. $/A. No delay .....................---.............. I -1,780 62.7 1,116 3-day delay .......... .... I 1,768 62.0 1,096 6-day delay .....-..........- ................. .. 1,610 61.4 989 None ......------..... ... ..-- .............. --1,205 58.5 705 The results of the experiment indicate that significant economic losses are likely to occur if irrigation is delayed more than 3 days when re- lated to the estimated optimum time of application for greatest gross re- turn from tobacco. Ten varieties of tobacco were subjected to each of the irrigation vari- ables. The varieties could be placed in two groupings according to re- sponse as indicated by yield to irrigation treatment. The highest yield for varieties White Gold, Virginia Gold and Virginia 21, which were in one of the groups, was obtained with the "3-day delay" treatment. Yield was depressed by the "no delay" irrigation treatment for these varie- ties. The other group of varieties, Coker's 187, 178 Hicks, Golden Cure, Hicks, McNair 2, Vesta 5 and 402, gave no indication that the "no-delay" irrigation treatment was detrimental. Yield was depressed for all varie- ties in the experiment by the "6-day delay" and no irrigation treat- ments. (See also Project 555, Agronomy Department and Suwannee Val- ley Station.) Annual Report, 1961 PASTURE PROGRAM AND BREEDING SYSTEMS FOR BEEF PRODUCTION ON FLATWOODS SOILS OF CENTRAL AND NORTH CENTRAL FLORIDA State Project 627 J. M. Myers The pasture program on which irrigation was used as a cultural prac- tice was managed in accordance with established procedure. Rainfall during the period July to December, 1960, was above average, but dur- ing the period January to June, 1961, it was slightly below average. Two applications of irrigation were applied to the pastures during the dry period in May and June, 1961. The pasture program which included irrigation produced 394 pounds of calf per acre and 7175 pounds (dry weight) of forage during the 1959-60 grazing year (October to September). These yields represent the highest production levels of all the programs tested. (See also Project 627, Agri- cultural Economics, Agronomy, Animal Science and Soils departments.) CURING BRIGHT-LEAF TOBACCO GROWN UNDER DIFFERENT LEVELS OF NITROGEN Hatch Project 758 J. M. Myers Tobacco harvested at optimum maturity produced 4.6 percent more cured leaf than tobacco harvested 1 week earlier or 1 week later. Ma- ture leaf was valued at $0.01 per pound more than leaf harvested pre- maturely but was valued at $0.025 per pound less than overmature leaves. The experiment furnishes overwhelming evidence that a signifi- cant reduction in crop value is obtained when tobacco is harvested be- fore it is fully mature. Indications are, however, that no economic loss results when tobacco is harvested 1 week after the time of estimated optimum maturity. A linear relationship was found to exist between levels of coloring temperature and maturity at harvest as measured by leaf quality. Im- mature tobacco gave lowest quality and overmature tobacco highest quality irrespective of coloring temperature. Quality of the cured leaf was approximately the same for coloring temperatures of 90, 95, 100 and 105oF but was depressed considerably by 110F. A significant reduc- tion in development of Brown spot ("frog eye") was noted when the coloring temperature was 105F or greater. An inverse relationship was found to exist between maturity at har- vest and nitrogen fertilization levels as indicated by leaf quality. The 96-pound level of nitrogen produced highest quality when harvested at the overmature stage, while the 48-pound level gave highest quality when harvested immature. Coloring temperatures of 90, 95, 100 and 105F produced approximately the same quality for each of the nitrogen levels, but for the 1100F temperature a linear relationship existed, with the 48- pound nitrogen level producing highest quality and the 96-pound level producing lowest quality. The quality differential between these treat- ments was valued at $0.05 per pound of tobacco. (See also Project 758, Agronomy Department.) OPEN-DITCH SYSTEMS FOR WATER TABLE CONTROL ON NORTH CENTRAL FLORIDA FLATWOODS SOILS State Project 946 J. M. Myers Two subirrigation and 2 drainage cycles were run on Leon sand at the Beef Research Unit during the winter of 1960-61. Water table chang- Florida Agricultural Experiment Stations es in the soil between ditches spaced 67, 133 and 200 feet apart were measured. Figure 2 shows the change of water table at midpoint of the 3 ditch spacings as a function of time during a subirrigation cycle. After 48 hours of subirrigation, the hydraulic head of the ditch was approximate- ly 1.7 feet higher than the water table in the soil at the midpoint between the 200-foot ditch spacing; and after 210 hours, the head differential was still 0.8 foot. The maximum water table in the soil at the midpoint between the 67-foot ditch spacing was obtained approximately 72 hours after subirrigation started. The head differential at that time was 0.7 foot. The depth to water table in the soil at the midpoint between the 200- foot ditch spacing had been lowered less than 0.25 foot after 48 hours of drainage with a hydraulic head differential of 2.3 feet. More than 10 days was required to obtain a 1-foot change in the water table at the midpoint between the 200-foot ditch spacing. Approximately 20 hours was required to lower the water table 1 foot at the midpoint between the 67- foot ditch spacing with an approximate average hydraulic head differ- ential of 0.7 foot. The results of this experiment on Leon sand indicate a need for rela- tively close ditch spacing, and consequently, high land development cost, for growing crops sensitive to precise water table control. (See also Project 946, Soils Department.) 2t7 2..4 . 2 / S 1.5 1.2 -a- 200 ft. spacing S .... 133 ft. spacing S / J--- 67 ft. spacing o 0.9 .6 / 0 45 o0 135 180 225 Tlme (hours) Figure 2.-Change in depth to water tables with time at midpoints of three ditch spacings on Leon sand. Subirrigation cycle: 1415, 12/1/60- 1150, 12/10/60. IMPROVING METHODS OF HANDLING POTATOES AT THE PACKING HOUSE State Project 1017 E. K. Bowman and E. S. Holmes During this year 2 approaches were taken in handling potatoes. The first approach was using a dump truck as a substitute for the bulk body normally used. The second approach was the pallet box method. Annual Report, 1961 45 Figure 3.-Forklift truck placing pallet boxes onto flatbed truck at packing house. I I. Figure 4.-Holding bin with dump-bed load of potatoes. :. ~~L---- ___ Florida Agricultural Experiment Stations Bulk Dumping.-Tests were run during early, mid and late season by dumping potatoes onto a special floor and floating them into the flume. The injury analysis showed similar results to the previous year. Approximately 300 gallons per minute of water was available for floating the potatoes out of the bin, and this was found to be insufficient. Indi- cations were that about twice that much water was needed. Time studies did not materially add to the data obtained last year because of the unexpected problems encountered and resulting inconsistencies in the op- eration. Pallet Boxes.-An experimental pallet box operation consisting of pal- let box dumper, skate wheel conveyors, pallet boxes, a flatbed truck and forklift tractor equipment was set up at a commercial packing house near Elkton, Florida. At the packing house, boxes were handled in a cycle that simulated a commercial operation, including temporarily hold- ing the potatoes prior to dumping them into the packing line. The rate at which potatoes were harvested into pallet boxes was about the same as that for harvesting into hopper bodies. Tuber injury showed that the experimental pallet box operation com- pared favorably with the regular hopper-body operation. Preliminary time study data indicated that an industrial forklift trac- tor could feed a packing line at a rate of about 300 hundred-weight per hour. The pallet box dumper capability was indicated to be as much as 735 hundred-weight per hour under favorable conditions. (See also Project 1017, Agricultural Economics.) DEVELOPMENT OF EQUIPMENT FOR THE APPLICATION OF SOIL FUMIGANTS TO THE MINERAL AND ORGANIC SOILS OF CENTRAL FLORIDA State Project 1020 E. S. Holmes During the year, liquid fumigants were applied to test plots at the Central Florida Station according to a predetermined experimental de- sign. Applications were made in the following way: 1. Conventional shank at 6-inch depths and 12-inch row spacing. 2. Conventional shank at 6-inch depths and 6-inch row spacing. 3. Shear blade with fan spray nozzles making complete horizontal coverage at 6-inch depths. 4. Specially built plow with fan nozzle to inject fumigant in an 8-inch band. Initial experiments with row fumigation for 30-inch row spacing were unsuccessful because of adverse weather conditions. A new idea for a band injector was devised as shown in Figure 5. Preliminary field trials indicated that an 8-inch width of soil could be treated satisfactorily with this T shank injector. (See also Project 1020, Central Florida Station.) A CONTINUOUS HARVESTING-CURING SYSTEM FOR BRIGHT LEAF TOBACCO Hatch Project 1034 I. J. Ross and J. M. Myers The smoking characteristics and physical properties of bright leaf to- bacco can be controlled during bulk curing by suitable adjustment of temperature and drying rates during the coloring period. An experiment completed in 1960 has shown that these 2 variables act in opposition to Annual Report, 1961 47 each other. An increase in the coloring temperature increases the smok- ing strength and the filling value, while an increase in the rate of water removal reduces the smoking strength and the filling value. Experiments are being continued on other phases of bulk curing. Work this year includes studies on the density of tobacco in boxes; air flow rates during coloring, leaf drying and stem drying; and techniques for ordering and storing the cured leaf. A continuous harvesting and bulk curing system is being tested on the tobacco research farm. The system is designed so that 2 men work- ing 40 hours per week during the tobacco harvesting season can harvest and cure approximately 4 acres of tobacco. Four boxes of tobacco are harvested each work day. The tobacco is cropped manually by 2 men riding on a mechanically-driven harvesting aid. The tobacco is placed in a bulk box on the harvesting aid as it is harvested. After a box is filled, it is carried to and placed in a bulk curing unit. The bulk curing system consists of 10 separate curing units, each holding 2 bulk boxes in which the tobacco is completely cured and ordered. The functional specifications for bulk curing tobacco were determined from the experi- ment summarized in the first paragraph. The continuous harvesting and curing system is being evaluated on the basis of labor input, operating costs and yield and quality of the tobacco produced. (See also Project 1034, Agronomy Department and Su- wannee Valley Station.) SUMMER COOLING OF CATTLE IN THE FEED LOT State Project 1067 E. S. Holmes During the year 30 beef animals weighing about 600 pounds were ran- domly divided into 3 lots to study the effect of summer cooling by a fan thermo-statically controlled to operate only when the temperature was above 75F. Ten animals were under fan, and the other 2 lots were Figure 5.-T-shank fumigant injector with 9 holes 1/64 inch in diameter and 1 inch apart, for mounting on rear of tractor. 2.. L:.. . W" ":. Florida Agricultural Experiment Stations controls. During the test period beginning June 20, and running for 106 days, temperatures were recorded with thermocouples in 6-inch black globes at 6-foot heights in the cooled and non-cooled pens. There were 18 days in which the air temperature in the barn went above 90F and 57 days above 85F. It was interesting to note that only 8 times during the test interval did the humidity in the shed go below 60 percent. Data from the weight gains and carcass grades were analyzed, and there was no significant difference in weights. The carcass grades of the cooled lot were generally higher than the non-cooled lots. (See Project 1067, North Florida Station.) EQUIPMENT FOR REMOVING NON-FREE-FLOWING GRANULAR MATERIALS FROM BULK STORAGE Hatch Project 1082 I. J. Ross The difficulty involved in removing non-free-flowing materials from bins by present methods is the major obstacle in automating handling and processing systems for these feeds. From an analysis of the problem it appears that an inexpensive device for positively unloading bins of non-free-flowing materials such as citrus pulp can be developed. Such a device should encourage the use of bulk storage and provide a necessary equipment component for completely automating feed handling. Plans have been made to construct a laboratory system for handling granular materials. This system will include 2 common types of com- mercially available hopper-bottom bins. Several types of mechanical un- loaders will be developed and installed in these bins, and their effective- ness in unloading non-free-flowing materials will be determined. The ef- fect of compaction, kind of material, bin unloading techniques, bin shape and bin hopper slope on feed removal from the bins will be studied. PRELIMINARY NON-PROJECTED STUDIES Mechanical Harvesting of Vegetables.-Harvesting by Riding.-In the development of functional specifications for harvester aids, 1 important question is whether the picker should ride or walk. During the year, in cooperation with the Department of Vegetable Crops, attention was given to this point. Exploratory picking tests were carried out on small plantings at the Horticulture Farm on endive, broccoli, southern peas, tomatoes and cucumbers, using an experimental, self-propelled harvester aid to ride the pickers and transport the product. Harvesting rates per worker, for all crops except broccoli, were higher with pickers riding on the harvester aid as compared to walking. Longer test runs were made using the harvester aid on commercial plantings of eggplant and southern peas. The harvesting rate on egg- plant was 17.7 percent higher with the harvester aid and on southern peas was as much as 50 percent higher as compared to picking in the conventional manner by walking. The data are not conclusive but suggest merit in the possible use of harvester aids as a means to reduce the labor input of the vegetable harvesting operation. Mechanical Cutter for Southern Peas.-A small plot of Florida 7809 peas was planted for mechanical harvest during the year. This was a high pod setting line. The crop set well but was inclined to vine heavily into the middles. Finger guides only along the outer edges of the row gave relatively poor results (only 54 percent of the peas were machine cut). Fair results were obtained with flexible guides that went under Annual Report, 1961 the vines about 12 inches from the base of the plant. These guides also had fingers that lifted the vine about 3 inches over the cutter bar. (E. S. Holmes.) E'" 4' I' ' J,. W_ Figure 6.-Workers cutting endive while riding on a harvester aid machine. Forced Air Precooling of Citrus Fruit.-This is a cooperative project with the U.S. Department of Agriculture, Transportation and Facilities Research Division, Agricultural Marketing Service. The project was de- signed to determine the optimum conditions of operation for forced air precooling of citrus fruit in pallet boxes, bulk and consumer packages and the effects on subsequent decay and physiological breakdown of the fruit. Small temperature and humidity control chambers located in the Agricultural Engineering Building plus 1 large control chamber at the Fruit Crops packing house will be used to carry out this work. During the year time has been devoted to assembling and checking equipment with which to carry out this project. (E. S. Holmes.) High Moisture Shelled Corn in Air-Tight Storage.-In air-tight storage the normal respiratory processes of the grain are halted with the con- version of the oxygen in the initially present interstitial air into carbon dioxide. Since little or no further respiration occurs because of the lack of oxygen, the heating that occurs in high moisture grain in open storage does not occur. Furthermore, most storage molds, insects and rodents cannot grow under the anaerobic conditions in air-tight storage. Shelled corn at a moisture content at approximately 25 percent wet basis is being stored in 4 sealed containers. Each container holds ap- proximately 7 bushels of shelled corn. Corn has also been stored in a fifth container utilizing the zero-pressure or breather principle. This storage unit allows a limited quantity of gas exchange between interstitial gases and ambient air. The pressure and the volume of oxygen and carbon dioxide present in the storage units are being measured. Information gained from ex- perience with these storage units should give an indication of the feasibil- ity of this type of storage under Florida weather conditions. (I. J. Ross.) Florida Agricultural Experiment Stations AGRONOMY Research on bulk handling and curing of flue-cured tobacco was be- gun in cooperation with Agricultural Engineering with encouraging re- sults the first season. Two projects were revised under new numbers. Research on more detailed biochemical aspects of crop nutrition has been expanded with assignment of additional laboratory space and ac- quirement of a number of much needed items of laboratory equipment. Research on 31 older projects was continued with satisfactory results as reported below. PEANUT BREEDING FOR SUPERIOR TYPES FOR MARKET AND FOR LIVESTOCK FEED Hatch Project 20 W. A. Carver Florida Station pedigreed line number 392-12, a jumbo runner peanut, was given the name Florigiant and officially released by the Florida Ex- periment Station on January 16, 1961. Florigiant is a complex hybrid. Its ancestry includes Spanish, North Carolina runner and Virginia types. The final cross in the pedigree of Florigiant was made in 1951. Hybrids between breeding lines and varieties were made in 1960, the objectives being to improve present lines having small and large seed in soundness, uniformity and yield. Parents used in these crosses were Florispan Runner, Early Runner, Dixie Runner, 392-12 and 420 (Dixie Runner x 392-12). Four different pedigreed lines of Dixie Runner were intercrossed with the hope of restoring some of this variety's yielding ability. Twenty-two varieties and breeding lines were grown in variety tests. Line 420-215-1 ranked highest in yield of sound and mature seed, Early Runner ranked seventh, Florigiant ranked eighth, common runner ranked last and Dixie Runner next to last. A yield trial using regular and peg (small) seed of Early Runner and Dixie Runner showed no advantage for peg seed. The same weight of seed per row was planted from each sort. The Florigiant peanut variety is described in Florida Agricultural Ex- periment Station Circular S-129, February 1961. PASTURE GRASS AND LEGUME RESPONSES TO VARIOUS FERTILIZER AND MANAGEMENT PRACTICES Hatch Project 295 G. B. Killinger and H. C. Harris Starr, Common (Pearl or Cattail) and Gahi-1 millets were compared at 2 levels of nitrogen fertilization as shown in Table 3. All millet plots received a uniform application of 622 pounds per acre of an 8-8-8 fertilizer at planting and additional nitrogen applied after each cutting. It appears these varieties of millet were unable to utilize the higher application of nitrogen during the 1960 season. This lack of response to 545 pounds of nitrogen is not unusual as the yield of other forage and grain crops are often depressed by extreme rates of nitrogen fertilization. Potassium nitrate equivalents in the dry forage ranged from less than 1 percent to over 4 percent. No toxic condition was noted when green and/or dry forage was fed to sheep. White clover yields of 6,999 pounds per acre dry forage from Louisi- ana S-1 was recorded as the highest yield of all varieties harvested from a 2-year-old stand. A yield of 5,077 pounds of dry forage per acre from Annual Report, 1961 Nolin's Improved White was the highest yield from a first year stand. Louisiana S-1 red clover, Nolin's red and Pennscott red clover yielded 7,455, 7,296 and 7,024 pounds per acre of dry forage, respectively. Red clover as an annual crop warrants serious consideration by livestock producers in Florida. TABLE 3.-LEVELS OF NITROGEN FERTILIZATION OF STARR, COMMON AND GAHI MILLETS. Variety Lbs. Oven Dry Forage per Acre 214 lbs. N 545 lbs. N Starr .............. ........ ......... 6,277 5,227 Common .......................... 6,261 6,261 Gahi-1 ..............- .................. 7,304 6,948 A new hybrid bahiagrass, Tifhi-1, yielded 10,691 pounds per acre of dry forage from 5 cuttings as compared to a 10,067 pound yield from Pensacola bahiagrass. This 624 pound increase in dry forage is not suf- ficient to justify the Tifhi-1 variety. Seed from Tifhi-1 plantings must not be harvested and planted because of lesser yields in following gen- erations. EVALUATION AND IMPROVEMENT OF FORAGE AND COVER CROP LEGUMES OTHER THAN CLOVERS AND LUPINES State Project 301 J. R. Edwardson, E. S. Horner and F. H. Hull Evaluations of strains and species of crotalaria and alfalfa for adap- tation to the environmental conditions found at Gainesville were con- tinued. Backcrossing cytoplasmic male-sterile lines of Crotalaria mucronata by normal lines is continuing with the objective of converting several nor- mal lines to the male-sterile condition. These converted lines will even- tually be used in producing hybrids which will be incapable of producing seed by self pollination. Studies of the inheritance of fertility restora- tion in cytoplasmic male-sterile lines is continuing. Selection for increased persistence in alfalfa was continued. Fourth- cycle seed was harvested from surviving plants in 3-year-old plots. Re- sults of tests conducted in 1959 and 1961 indicate that the selected strain is equal to commercial Hairy Peruvian in forage production the first year after seeding and is significantly higher yielding the second and third years because of better stands. FLUE-CURED TOBACCO IMPROVEMENT Hatch Project 372 Fred Clark Thirty advanced breeding lines and 16 commercial varieties were test- ed. All of the advanced breeding lines were tested on nematode infested soil. A belt-wide regional test was also conducted with 8 advanced lines from the several tobacco producing states. Included in the test were Florida Agricultural Experiment Stations North Carolina 8069-5 and F22-2. North Carolina 8069-5 has been re- leased by North Carolina as North Carolina 95. F22-2 will be released for the 1962 season. F22-2 led all regional advanced breeding lines in all locations in all states. It had high resistance to nematodes and to brown leaf spot. F22-2 is unique in that it combines the highest yields of any advanced breeding line with a high level of nicotine. This has been a limiting factor in developing varieties having high yields and ac- ceptable nicotine content. F22-2 also has other desirable chemical con- stituents and compares well with Hicks and 402, the 2 leading commer- cially grown varieties in Florida. CORN BREEDING Hatch Project 374 E. S. Horner and F. H. Hull Studies were continued to evaluate different methods of improving yield of hybrid corn. Three recurrent selection experiments, utilizing as test- ers an inbred line, a single cross and a heterogeneous variety, have been carried on for 3 cycles. Tests were conducted in 1960 to measure the relative amount of progress made. The results show that in each experi- ment general combining ability was improved significantly by the first 2 cycles of selection, regardless of the type of tester used. However, no further improvement in general combining ability was made by the third cycle in any of the 3 experiments. On the other hand, combining abil- ity with the 2 specific testers (the inbred line and the single cross) was improved as much by the third cycle as by the second in the 2 experi- ments involving these testers. These results indicate that it will be pos- sible to improve yield more effectively with recurrent selection if a spe- cific tester rather than a general tester is used. In the experiment discussed above which utilizes a single cross test- er, no additional improvement was observed for the fourth cycle of se- lection. This may be explained, at least in part, by the fact that no high-yielding hybrids were saved unless they also had low ear placement, good standability and resistance to weevil damage. For this reason the selection differential for yield was considerably lower in the fourth cycle than for the previous cycles. Two cycles of selection based only on yield of inbred lines were ef- fective in improving general combining ability in a fourth experiment. Florida 200, Dixie 18 and Coker 811A were the leading hybrids in the commercial variety tests. (See also Project 374, West Florida, North Florida and Suwannee Valley stations.) EFFECT OF COPPER, MANGANESE, ZINC, BORON, SULFUR AND MAGNESIUM ON THE GROWTH OF GRAIN CROPS, FORAGE CROPS, PASTURES AND TOBACCO Hatch Project 440 H. C. Harris, V. N. Schroder and Fred Clark Oats and ronphagrass grown on virgin Leon fine sand from the Beef Research Unit area and given a complete fertilizer were not affected either beneficially or detrimentally by additions of magnesium acetate at rates up to 2,000 pounds per acre (equivalent to 375 pounds MgO). The oats out-yielded the ronphagrass during February, March and April but had a shorter period of production. Sesame grown on this same soil responded to all the major fertilizing elements and gave a very positive response to the addition of copper. Annual Report, 1961 53 The studies with sesame at the greenhouse are being continued. In the past, copper, boron and molybdenum have increased the yield of several crops when grown on this soil. PERMANENT SEEDBEDS FOR TOBACCO PLANTS State Project 444 Fred Clark Excellent production of plants was obtained in the seventeenth year for the permanent beds. Plants were used to set experimental plots of the several other tobacco research projects. (See also Project 444, Su- wannee Valley Station.) NUTRITION AND PHYSIOLOGY OF THE PEANUT Hatch Project 488 H. C. Harris, V. N. Schroder and Fred Clark A field experiment involving spacing, fertilization and other treatments is being conducted in a manner similar to the one reported last year. The variety being grown is Florigiant. A test on the nutrient require- ments of this variety on soil from the same area is being conducted at the greenhouse. It is too early to draw conclusions. Foliar applications of phosphorus and boron were applied to peanuts in pot experiments and field experiments at different stages of growth. In general the foliar application reduced both the growth of the foliage and the nut yield by about 10 percent. Neither the maturity nor the quality of the peanuts seemed to be affected. FERTILIZATION AND CULTURE OF FLUE-CURED TOBACCO Hatch Project 555 Fred Clark and H. C. Harris Four times of irrigation, 4 nitrogen rates (42, 72, 96 and 120 pounds per acre) and 10 commercial varieties of tobacco were tested. The "on time" and "3-day delay" irrigation treatments produced the best yields, quality and price. The 3-day delay of irrigation produced over 500 pounds more tobacco than no irrigation, giving a total increased acre value of $350. Seventy-two and 96 pounds of nitrogen per acre con- tinued to be the best nitrogen treatments. The interaction of nitrogen rates 72 and 96 pounds and irrigation treatments on time and delayed 3 days produced the highest yields and dollar value. C-187-Hicks, Gold- en Cure, Vesta 5 and Hicks were the highest yielding varieties. Six fumigants were tested for control of nematodes. W-85, Telone and DD produced more than 700 pounds over the no treatment with in- crease in gross value of over $490 per acre. A side-dressing experiment was conducted comparing a 4-8-12 fertil- izer with a 2-10-4 analysis plus 3 applications of a 13-0-44 nitrate of pot- ash. All nutrient levels were equal. The 4-8-12 fertilizer was superior to the 2-10-4 plus nitrate of potash. (See also Project 555, Agricultural Engineering Department and Suwannee Valley Station.) BREEDING IMPROVED VARIETIES OF WHITE, RED AND SWEET CLOVER State Project 600 E. S. Horner and F. H. Hull Breeding for increased persistence, productivity and disease resistance in white clover was continued. The procedure has been to propagate vegetatively superior plants which have lived through a summer and 54 Florida Agricultural Experiment Stations produced good fall growth, and to make continued evaluation of these clones in replicated plots. Twelve clones which have survived several years of elimination were intercrossed in 1960-61. A synthetic variety will be produced from this material for comparison with commercially available varieties. A second cycle of selection has been initiated with the establishment of a space-planted seedling nursery with seed obtained from intercross- ing 26 selected clones. IMPROVEMENT OF LUPINES BY BREEDING FOR YIELD AND INSECT AND DISEASE RESISTANCE Hatch Project 612 J. R. Edwardson and F. H. Hull' The Stemphylium resistant selection G. P. consistently outyielded com- mon bitter blue lupine and 2 varieties of sweet blue lupines in green weight. The same resistant selection produced significantly more seed than common bitter blue or sweet varieties of lupine. The G. P. selec- tion has been found to be resistant to both Stemphylium solani and S. botryosum. In yellow lupine, crossing programs were continued with the ultimate objective of transferring genes controlling resistance to bean yellow mo- saic virus and Phomopsis from agronomically undesirable species and varieties to commercially desirable varieties. PASTURE PROGRAMS AND BREEDING SYSTEMS FOR BEEF PRODUCTION ON FLATWOODS SOILS OF CENTRAL AND NORTH CENTRAL FLORIDA State Project 627 G. B. Killinger and H. C. Harris Clover and grass growth during the summer and fall of 1960 was near normal after a late spring had delayed early growth and grazing. The average yield of dry forage from the 5 programs, total crude protein per acre and treatment are shown in Table 4. TABLE 4.-AVERAGE YIELD OF DRY FORAGE FROM 5 PROGRAMS. Program ILbs. 0-10-20 Lbs. of Nitrogen Oven-dry Forage Crude Protein per Acre per Acre (Lbs. per Acre) (Lbs. per Acre) 1 450 180 6,951 806 2 300 0 5,317 766 3 500 0 6,207 792 60 6,878 4 700 0 6,640 933 60 7,496 5 900 0 6.688 897 60 7,662 Program 2, which received an application of 0-30-60 fertilizer with no nitrogen, produced the most economical forage of the 5 programs under test. 1 Cooperative with Crops Research Division, ARS, USDA. Annual Report, 1961 A low calcium supply in the soil under programs 4 and 5 was probably responsible for the lack of response to heavier fertilization applied to these programs. Approximately 50 percent of the forage consumed during the season was white clover. (See also Project 627, Agricultural Economics, Agricultural Engineer- ing, Animal Science and Soils departments.) HERBICIDAL CONTROL OF WEEDS IN CORN AND SOYBEANS State Project 747 M. Wilcox and E. G. Rodgers Promising herbicides were applied at several rates to field corn and soybeans at various stages of development in replicated field trials. The responses of the crop and weed species were observed and yields meas- ured where appropriate. Field Corn.-Several chlorinated aromatic fatty acid herbicides applied at late dough stage gave effective control of crotalaria. The least ex- pensive of the effective treatments was 2,4-D amine at % to 1 lb. per acre, which has USDA approval. Control of crotalaria by applications at lay-by or earlier will require further evaluation. Some herbicides at least as effective as those commercially available for general pre- emergence and post-emergence weed control in corn also require further evaluation. Soybeans.-The most promising herbicides tested were two thiolcar- bamates which controlled weeds for one month without damaging soy- beans. Soil incorporation studies of these compounds are under way in order to improve their performance. This project is terminated with this report. Future work will be in- cluded in State Project 1087. CURING BRIGHT LEAF TOBACCO GROWN UNDER DIFFERENT LEVELS OF NITROGEN Hatch Project 758 Fred Clark and H. C. Harris Tobacco with 3 rates of nitrogen-48, 72 and 96 pounds per acre-was harvested at 3 maturities-green, ripe and over-ripe. Five yellowing temperatures-90, 95, 100, 105 and 110 F-were used in the coloring of the tobacco. As the nitrogen increased from 48 to 96 pounds, the amount of green weight tobacco increased, while the ratio of green weight to cured leaf dropped. Seventy-two and 96 pounds of nitrogen produced the best yields and quality. Effects of maturity on yield were small; but there was a difference in price of over 3 cents per pound. There was an increase in the green to cured leaf ratio in favor of the ripe to overripe leaf. Coloring temperatures up to 105F had little effect on quality; how- ever, there was a loss of over 6 cents per pound at the 1100F level of color- ing. There was a small increase in the ratio of green weight to cured leaf in the temperatures above 100F. The interaction of maturity x ni- trogen was best with ripe tobacco at the 72-and 96-pound levels of nitro- gen. Over-ripe tobacco had the highest ratio of green weight to dry leaf with all levels of nitrogen; however, the 48-pound rate of nitrogen had the highest percent. The interaction of maturity x temperature was best with ripe to over-ripe tobacco cured at temperatures of 90 to 100 F. Temperatures above 100F gave the best percent of dry leaf to green weight. (See also Project 758, Agricultural Engineering.) Florida Agricultural Experiment Stations MEASUREMENT OF METEOROLOGICAL ELEMENTS OF THE MICROCLIMATE Hatch Project 760 G. M. Prine, V. N. Schroder, O. C. Ruelke, S. H. West2 and K. D. Butson' Temperatures within the microclimate of pangolagrass grown on level land and hilled land having north and south slopes were measured dur- ing cold periods in the winter. The average temperature of 4 locations on the south slope during days of measurement was 29.6F shortly be- fore daybreak, increasing to 96.4 F shortly after noon. Corresponding temperatures on the north slopes averaged 31.8F and 78.20F. The per acre yields of pangolagrass hay harvested at first cutting were 840 pounds on the south slopes, 117 pounds on the north slopes and 709 pounds on the level. Most of the pangolagrass was winterkilled on north slopes, and weeds had developed in its place. Several experiments probing into the effect of light on field grown corn indicated that light was an important factor limiting corn yield under conditions of good management and high plant populations. At 15,000 plants per acre Florida 200 corn plants which yielded 135 bushels per acre utilized 3.3 percent of total solar energy during the last 2 months of their life cycle. Calculations indicated that to have produced 200 bushels of corn per acre these corn plants would have required 4 percent efficiency in use of solar energy. There was no difference between forage yields of Florad oats in rows oriented in north and south versus east and west directions. In Janu- ary a severe freeze completely killed recently defoliated oats, while un- cut and defoliated oats with 2 weeks regrowth survived. The Florad oat is apparently very susceptible to cold damage when defoliated, so over- grazing or severe cutting should be avoided during periods of expected severe cold. BREEDING AND EVALUATING NEW VARIETIES OF SOYBEANS FOR FLORIDA State Project 761 Kuell Hinson' Recent predictions on future soybean utilization indicate that the de- mand for soybean protein will increase more rapidly than the demand for soybean oil. Therefore, emphasis is being shifted to combine high protein content of seed with high yield and good agronomic and disease resistance qualities. Single, double and 3-way crosses have been made to combine desirable genetic material. Early generation breeding ma- terial is still predominately segregated from crosses made to improve yield and maintain high oil; therefore, a period of 3 to 5 years will be required before high protein selections occupy a prominent place in the variety testing program. A genetic study was conducted to obtain information on the number of genes determining photoperiod response and their linkage relationship with genes determining 10 qualitative characters. F, populations were grown from Improved Pelican (very late) crossed with 9 genotypes having a photoperiod response adapting them to the northcentral states. Population size was adequate to sample a chromosome region approxi- mately 30 crossover units on either side of the gene involved. Three of 2Cooperative with Crops Research Division, ARS, USDA. 3 Cooperative w.th Un ed states Weather Bureau. Cooperative with Crops Research Division, ARS, USDA. Annual Report, 1961 57 the 10 chromosome regions sampled gave significant associations with photoperiod response as measured by flowering date. Since a relatively small percentage of the chromatin material was sampled, a large num- ber of genes having a measurable effect on photoperiod response is in- dicated. INTERRELATION OF ENVIRONMENT TO THE PHYSIOLOGY AND CHEMISTRY OF PLANTS II. ORGANIC ACID METABOLISM OF PLANTS IN RELATION TO MINOR ELEMENT NUTRITION Hatch Project 766 V. N. Schroder and H. C. Harris Peanuts were grown in nutrient solution to study the effect of various deficiencies. In general, healthy peanuts have a citrate to malate ratio of about 3:1 when the petioles of the leaves were examined. A lack of iron results in a disappearance of the malate or a much higher citrate to malate ratio. Additions of iron or other minor elements were made to the deficient nutrient solution, after which leaves and petioles were checked daily over a period up to 6 days. Deficient plants gave a rapid response (24 hours) to these additions as indicated by the increase in malate. The response to the treatment depended somewhat on the severity of the deficiency indicated by the color of the plant. Efforts to produce similar deficiencies in soil by adjusting the pH to very high levels have not given comparable results. EVALUATION OF INTRODUCED PLANT SPECIES AND VARIETIES Hatch Project 767 G. B. Killinger, W. A. Carver, (Regional S-9) A. J. Norden and F. H. Hull Grass, legume and miscellaneous agronomic species representing 350 accessions were received from the Regional Plant Introduction Station and planted in the introduction garden for forage and pasture evaluation. A Paspalum notatum escape plant was selected for pasture and/or turf from P.I. No. 227832 and has distinctly different characteristics than oth- er known P. notatum varieties. Erucastrum abyssinicum, P.I. No. 243913, has grown exceptionally well both summer and winter and is being test- ed as a cash oil seed crop. Pensacola bahia plants grown from irradi- ated seed are showing distinct changes in growth habit and may be useful as pasture or turf species. Pearl Spanish peanut introductions 246388 and 246391 were planted in yield trials in 1959 and 1960. The Spanette Spanish variety, released by the Georgia Station, averaged 43 percent more sound seed per acre than 246388 and 5 percent more than 246391. In 1960, an introduction from Israel, Number 258489, under the name of Dixie, was most productive of 9 entries in the test and led Spanette by 8 percent. Number 258489 (Dixie) appears to be a selection from Florispan Runner. For the third year significant date of planting x variety interactions were obtained with grain sorghums at Gainesville in regard to mean yield, plant height, days from planting to heading and days from plant- ing to maturity. This variation among sorghum varieties, in response to date of planting, should increase their potential usefulness in Florida, where there is need for a crop that can be planted at a time that will not greatly interfere with the growing and harvesting of a winter crop. Replicated trials comprising strains of oil seed crops from the genera Brassica, Ricinus and Sesamum were tested at Gainesville to determine their adaptation as potential new cash crops for Florida. Florida Agricultural Experiment Stations INFLUENCE OF CULTURAL PRACTICES ON THE INCIDENCE AND CONTROL OF INSECT INFESTATIONS IN FLUE-CURED TOBACCO Hatch Project 780 Fred Clark One acre of tobacco was planted, and 7 insecticide materials were tested. Acre yields were reduced by as much as 400 pounds where no insecticide was applied, and a loss of over $250 per acre occurred. (See also Project 780, Entomology Department.) SMALL GRAIN IMPROVEMENT BY BREEDING AND SELECTION Hatch Project 783 P. L. Pfahler A high positive correlation (r = +.89**) between second clipping and total forage production of oats was obtained, indicating that selection on the basis of second clipping data would be relatively effective. A sig- nificant positive correlation (r = +.29*) between growth type and total forage production was obtained, indicating that a semi-decumbent winter type variety would produce a larger amount of forage. Population density studies with 2 varieties of oats were conducted. Seedling emergence data indicated that high population densities resulted in a significantly lower percentage emergence. Apparently root secre- tions from germinating seedlings grown in close proximity lowered the percentage emergence. Although no variety x density interaction was detected, selective elimination of individual biotypes within these varie- ties may occur at high population densities. A highly significant date-of- clipping x variety interaction was observed; the upright, spring type va- riety Seminole produced large amounts of forage earlier in the season, while the semi-decumbent variety Floriland produced larger quantities later in the season. Population density could considerably alter the dis- tribution of forage production within each variety. A highly significant date-of-clipping x seed size was obtained, with larger seed producing larger amounts of late season forage. Larger amounts of stored seed reserves would not contribute materially to growth in this advanced pe- riod in the life cycle of the plant. Therefore, selection of large-seeded biotypes within these supposedly heterogenous varieties may be respon- sible. SUPPLEMENTAL HEAT AND LIGHT FOR THE PRODUCTION OF TOBACCO SEEDLINGS State Project 794 Fred Clark and E. B. Whitty Experiments over the past 4 years have shown plastic film to be su- perior to cheesecloth for tobacco planted covers. Plants again reached transplanting size earlier under plastic than under cheesecloth. Up to 300 pounds more tobacco was produced by plants grown under the plas- tic covers. Greater yields were also obtained from tobacco transplant- ed March 18, which was early for the 1960 season, and from the F22-2 variety. Hoagland's solution was the superior source of nitrogen in the cheesecloth covered planted, but no difference existed between plants receiving the various fertilizers under plastic film. Tobacco seedlings transplanted immediately after pulling produced better yields than plants held from 2 to 8 days before being transplanted. Annual Report, 1961 THE EFFECTS OF SIMULATED RAINFALL ON THE HERBICIDAL ACTIVITY OF DNBP AND SESONE Regional Research Project 839 E. G. Rodgers and M. Wilcox (Regional S-18) Leachability of simazine, atrazine, atratone and ipazine as influenced by rate of application and the amount and frequency of simulated rain- fall was studied under greenhouse conditions. These herbicides were ap- plied at 2 and 4 pounds active ingredient per acre to Greenville fine sandy loam soil which then received simulated rainfall in amounts vary- ing from 1 to 16 inches in 7 to 28 days. Each herbicide applied at 4 pounds per acre commonly was leached to greater depths by a given quantity of simulated rainfall than the same material applied at only 2 pounds per acre. Abnormalities of cucum- ber and oat seedlings grown in treated soil taken from various 1-inch horizons to a maximum depth of 6 inches served as the basis of evalua- tions. A given quantity of water applied during a specific period of time appeared to move the herbicide or its effect downward to greater depths than the same amount of water applied over a longer period of time. More leaching occurred, however, in soil to which were applied greater total quantities of simulated rainfall. Oats were more sensitive than cucumbers to these herbicides. Based on the combined responses of oats and cucumbers, the most leachable material was atrazine, followed in decreasing order by atra- tone, simazine and ipazine. FORAGE AND PASTURE GRASS IMPROVEMENT BY BREEDING Hatch Project 850 W. A. Carver, D. B. Linden and F. H. Hull Inbred lines are being established in Pennisetum glaucum and P. spi- catum and in hybrid strains. Dwarf lines, which originated in the selling program, are being intercrossed and inbred to determine their heredity for future use as seed parents and for increasing forage yield through hybrid vigor. One millet-napiergrass cross possesses several millet-like characters and good winter hardiness. This plant is a hybrid between a tall, late maturing strain of P. glaucum and napiergrass. Forty-six millet-napier plants had been transplanted from the breeding nursery to permanent plots for study of forage quality and resistance to cold. Most of the plants were killed by cold during the winter of 1959-60. The regional millet variety test of 1960 showed the same variety rank as in 1959: Gahi-1, Starr, Hybrid SJ, Cattail No. 7, and Common. Starr was 10 percent lower than Gahi in green forage yield, and Hybrid SJ was 23 percent lower. The Digitaria collection includes 55 named species and 46 accessions without species designation, representing the largest assemblage of Dig- itaria in the United States. They are being evaluated and classified with- in the taxonomic sub-groups in preparation of an interspecific hybridiza- tion breeding program. Some entries with superior winter hardiness or aggressive growth habit are being tested directly as possible new varie- ties. Digitaria smutsii and Digitaria eriantha, primarily bunch types have shown the greatest winter hardiness, some with no winter killing in 3 years. Some of the introductions from Belgian Congo had a rate of growth faster than pangolagrass. These introductions survived their first winter in Florida as well as pangola did. Florida Agricultural Experiment Stations HERBICIDAL CONTROL OF WEEDS IN PEANUTS State Project 886 M. Wilcox and E. G. Rodgers A comparison was made of weed control activity with and without soil incorporation of thiolearbamates and other promising herbicides for use in peanuts. Herbicidal activity was generally greater with incorporation, the increase being greater with the thiolcarbamates. Yield data from another field trial of 60 herbicidal treatments at vari- ous rates and growth stages show considerable promise for several new herbicides. In addition to those previously reported, R-1607 shows prom- ise for control of both broadleaf weeds and grasses. Further evaluations are underway. (See also Project 886, West Florida Station.) ROTATION AND FERTILIZATION OF FIELD CROPS State Project 900 E. G. Rodgers and Fred Clark The study of 10 crop rotation systems involving 4 levels of fertilization on 9 different crops initiated in 1958 and modified in 1960 has been con- tinued. Response of all crops to fertilization was satisfactory. Corn showed a marked yield increase in response to high nitrogen applica- tions. Corn grown in alternating years produced higher yields than corn grown each year on the land. Tobacco yields were higher following fal- lowing than when following corn in the rotation. Rotation and fertiliza- tion effects on chemical content of the crop plants have been inconclu- sive. Other specific effects of the rotation systems can be determined only after a much longer evaluation period. (See also Project 900, Su- wannee Valley Experiment Station.) TESTING SOYBEAN BREEDING LINES AND VARIETIES State Project 909 Kuell Hinson" Approximately 500 soybean breeding lines were planted at Gainesville, Live Oak and Zellwood to compare their performance with the best avail- able commercial varieties. The Zellwood nursery was not harvested be- cause of excessive stinkbug damage. However, data were collected to permit elimination of lines with undesirable agronomic and disease qual- ities. Of the 388 lines tested for the first time at Gainesville and Live Oak, 39 yielded more and 60 yielded essentially the same as the Jack- son check. All 99 lines have satisfactory agronomic and disease quali- ties and will be tested again at both locations. More than 100 lines tested in previous years were tested again. F55-822, a potentially early ma- turing variety for north central Florida, has a 4-year average yield 22 percent above Jackson at Gainesville and a 3-year average yield 11 per- cent above Jackson at Live Oak. F58-3734, a potential variety of medium to late maturity, has a 2-year average yield 35 percent above Jackson at Gainesville and was 20 percent above Jackson at Live Oak in 1960. The parent line from which F58-3734 was selected averaged 19 percent above Jackson at Gainesville and Live Oak over a 2-year period. F55-822 and F58-3734 will be recommended for variety release if their relative superi- ority to Jackson is maintained in 1961. (See also Project 909, Suwannee Valley and Central Florida stations.) SCooperative with Crops Research Division, Agricultural Research Service, USDA. Annual Report, 1961 Figure 7.-Photograph showing the effect of treatments on alfalfa: complete fertilization, including minor elements (28); same treatment ex- cept without molybdenum (24); and same as 28 except without boron (20). Figure 8.-Close view of extreme boron deficiency of alfalfa. Florida Agricultural Experiment Stations THE INTERRELATED EFFECTS OF MINERAL NUTRIENT DEFICIENCIES, ENVIRONMENT AND HEREDITY ON THE NITROGEN METABOLISM OF PLANTS Hatch Project 950 H. C. Harris In order to have plant material for the study of the effects of nutrient deficiencies on biochemical relationships within the plant, an effort was made to grow plants with deficiencies. Hairy Peruvian alfalfa was grown on Arredondo loamy fine sand and Ladino and white clovers on Leon fine sand at the greenhouse. Several deficiencies developed. An application of copper or sulfur increased the yields of all these crops. Zinc ap- pared to be harmful to both alfalfa and Ladino clover. Boron greatly increased the yield of alfalfa (Figures 7 and 8) but had little effect on the other crops. Cobalt, at the rates applied, seemed to be harmful for alfalfa and Ladino. An application of vanadium significantly increased the yield of alfalfa and Ladino, suggesting the possibility that vanadium may be of value on some Florida soils. In a similar test, low temperature seemed to kill lupine where boron or lime was not applied. Chemical work on the plants thus grown is only in the early stages, but it appears that nutrient deficiencies have a tremendous effect on the composition of the plants. Color of some legume seeds appears to have an effect on viability and biochemical changes. CYTOLOGY AND GENETICS OF RADIATION INDUCED ALTERATIONS IN CYTOPLASMIC FACTORS CONTROLLING MALE-STERILITY IN CORN State Project 969 J. R. Edwardson Seed of Minnesota A158T(BC.) and A158 corn were treated with gam- ma radiation of 10,000, 20,000, 30,000 and 40,000r. Seed of both lines which were not irradiated served as controls. All seed were planted in a completely randomized design, in vermiculite in flats. Height meas- urements were begun 1 week after planting and taken once a week in 3 succeeding weeks. Analysis of variance was applied to the height meas- urements. Significant differences in height were found between treat- ments, lines, dates and treatment and line interaction. A158T plants were consistently taller than A158 plants in all treatments except at 20,- 000r, where the lines produced plants with identical mean heights. There was no significant difference between the controls in height. The dif- ferential response to radiation damage is probably cytoplasmic. EFFECT OF AGE OF SOD ON YIELD OF BAHIAGRASS AND SUBSEQUENT FIELD CROPS State Project 971 A. J. Norden In this study, previously designated plots are seeded each year to bahiagrass until a period of 5 years has elapsed, after which time all plots are planted to a cultivated field crop to determine the effect of age of sod on field crop production. Seasonal records are maintained to determine the rate and extent of decline of the bahiagrass plots. In cooperation with Dr. V. G. Perry the soil of each plot is examined for changes in the numbers and species of nematodes. Covariance an- alysis of the 1960 data indicated that of the 8 species of nematodes iden- Annual Report, 1961 tified, the sting nematode, although present in fewer numbers than sev- eral of the other species, had the most deleterious effect on the yield, ear height and plant height of corn. Soil samples from each plot are taken yearly to determine availabil- ity of nutrients, and an attempt is made to lessen soil heterogeneity be- tween plots. From 1960 corn yield data designed to determine soil hete- rogeneity, the plot means involved in the "years in bahiagrass vari- able" were not significant statistically. Positive correlations were ob- tained, however, between amount of available calcium and growth of corn and yield of grain, indicating that even though relatively large ap- plications of dolomitic limestone were made in 1959, further applications are necessary to remove this limiting factor. THE PHYSIOLOGICAL AND ECOLOGICAL RESPONSES OF FORAGE CROPS TO DIFFERENT ENVIRONMENTS EFFECTED THROUGH MANAGEMENT PRACTICES Regional Research Project 998 G. M. Prine, V. N. Schroder, (Regional S-47) O. C. Ruelke, S. H. West' and K. D. Butson7 Studies of perennial grasses fertilized with nitrogen in the fall to pro- duce hay for the winter have been expanded. The growth retardant maleic hydrazide, sprayed on the regrowth of grasses at the rates of 2 and 6 pounds per acre after harvesting hay in the fall, reduced the percentage of winter-killed plants and increased the hay yield of the first cutting the following spring. Twelve pounds per acre of maleic hydrazide injured the plants, reduced the stands and reduced the yield the following spring. In general, growth retardants were less effective in preventing winter injury when temperatures were consistently cold than when winter temperatures were alternately cold and warm. Winterkill of pangolagrass receiving high rates of nitrogen fertilization in the fall (200 to 400 pounds of N per acre) was not successfully prevented by applying rates of P20 and K2O up to 200 pounds per acre. However, increasing the rate of KO0 did decrease the amount of winterkill slightly. A technique of growing alfalfa seedlings under conditions of infre- quent irrigation in an unshaded greenhouse during the summer shows promise for screening alfalfa plants tolerant to heat and high moisture stress. Alfalfa plants survive better on a slight hill than they do on nearly level land-even if the hill is only a fraction of an inch high. New research was initiated to substantiate this observation and to determine if planting alfalfa on low, flat beds will effectively increase longevity of stands. A CONTINUOUS HARVESTING-CURING SYSTEM FOR BRIGHT LEAF TOBACCO Hatch Project 1034 Fred Clark This is a new project begun March 1, 1961. Three acres of the Hicks variety were grown in a special row arrangement designed for the pro- posed system of harvesting. Harvest was only about half done at the time of this report, but it may be said that the partly mechanized sys- tem was working about as predicted. 0 Cooperative with Crops Research Division, Agricultural Research Service, USDA. 7 Cooperative with U. S. Weather Bureau. Florida Agricultural Experiment Stations Preliminary work on bulk curing in the 1960 season was done in 10 small laboratory size curing units. A 3 x 3 factorial design experiment for curing included 3 rates of coloring and 3 rates of drying. The Hicks variety of tobacco was used for the tests, and a sample of leaf was cured in both the bulk system and in the conventional barn for comparative purposes. Leaf quality comparisons were the most important fac- tors studied in the 1960 tests. Both physical and chemical evaluations were made, and it was shown that bulk curing gives a product similar in chemical composition and physical properties to that obtained by the barn cure. Certain of the coloring and drying rates produced a better ratio of cured leaf to green weight without loss of quality, and this fac- tor is of economic importance. (See also Project 1034, Agricultural Engi- neering.) INDUCED MUTATION RATE MODIFYING AGENTS IN OATS Hatch Project 1036 A. T. Wallace Seeds of the Victorgrain variety of oats, which is susceptible to the fungus Helminthosporium victoria, were irradiated with Cobalt-60 gam- ma rays, and the second generation was screened for mutations at the locus controlling the disease. The standard mutation rate of seeds with 10 percent moisture content at 22C has been found to range from 1.3 to 8.5 x 10-" per roentgen at the locus. Results now show that this rate can be modified with pre- or post-irradiation seed treatments. A number of treatments were tested with a series of doses. The maximum muta- tion rates for each series of treatments are as follows: Seeds with 6.8 percent moisture = 24.4 x 10-/r/1 at 10kr. Seeds with 6.8 percent mois- ture but wet immediately after irradiation = 25.8 x 10-8/r/1 at 20kr. Seeds heated for 1 hour at 85C after irradiation = 24.6 x 10-'/r/1 at 10kr. Seeds heated for 1 hour at 85C before irradiation =14.3 x 108-/r/1 at 20kr. Seeds soaked for 24 hours at 22C before irradiation = 113 x 10-'/r/1 at 2.5kr. Seeds in absence of oxygen during irradiation 24.6 x 10-'/r/1 at 10kr. Seeds in absence of oxygen during irradiation and stored in nitrogen =41.2 x 10-8/r/1 at 10kr. Seeds at dry ice temperatures before irradiation = 4.9 x 10 8/r/1 at 20kr. Seeds irradiated with ultraviolet light for 1 hour before being irradiated with gamma radiation = 31.8 x 10-'/r/1 at 10kr. This is the first report that gamma radiation induced mutation rates at a specific locus in higher plants can be modified. Generally, the re- sults indicate that factors which make the seed more radiosensitive will increase the mutation rate. Also they indicate that the agents that tend to trap free radicals may be used to increase the efficiency of ionizing radiations for the production of mutations. DEVELOPMENT AND EVALUATION OF AN INTEGRATED SILAGE AND GRAZING SYSTEM FOR DAIRY CATTLE State Project 1053 A. J. Norden In 1961 at the Hague Dairy Unit a 4 replicated test was initiated to compare the forage and grain yield obtained from a consecutive plant- ing of spring corn, summer sorghum and fall oats with the standard pro- cedure of spring corn and fall oats. Application of plant nutrients is made on the basis of soil test results from samples taken annually from each plot. Seasonal fluctuations in the organic matter content of the soil will be exmained to determine the effect of the root systems in main- taining organic matter. Annual Report, 1961 In prior grain sorghum tests at Gainesville, significant date-of-planting x variety interactions were obtained, indicating the possibility of select- ing or developing sorghum varieties adapted to either early or late plant- ings. Therefore, satisfactory silage yields from sorghum may be possi- ble with July plantings. To determine planting date response within the sorghum species, more than 700 genotypes from the World Collection, including over 100 established commercial varieties, are being evaluated in single row plots at Gainesville in 1961. The genotypes will be plant- ed in 4 periods: April, May, June and July. Data on maturity, plant height, head development, insect damage and disease incidence are be- ing obtained. Promising genotypes from this 1961 test will be further evaluated in a replicated July planting in 1962 and subsequent years for yield of forage and grain, interval from planting to ensiling stage, ma- turity date, insect damage and disease resistance. (See also Project 1053, Dairy Science Department.) CHEMICAL CONTROL OF WEEDS IN FIELD CROPS State Project 1087 M. Wilcox and E. G. Rodgers This is a new project, initiated in the summer of 1961. Studies are underway in corn, soybeans and tobacco. (See also Project 1087, Cen- tral Florida and Everglades stations.) PRELIMINARY NON-PROJECTED STUDIES Field Crops Production on Flatwoods Soil.-The effect of 4 bed heights (0, 3, 6, and 9 inches), 5 populations (5, 10, 15, 20 and 25 thousand plants per acre) and 2 planting dates (March 25, 1960, and April 14, 1960) on the growth, development and yield of 2 varieties of hybrid corn (Florida 200 and Coker 811) grown on Flatwoods soils was measured in 1960. A curvilinear effect was indicated between bed height and grain yield of the March planting of corn and a linear effect between bed height and grain yield of the April planted corn. From the relationships, ap- parently an interaction exists, suggesting that bed height is a more im- portant factor in April plantings. Early planted corn is apparently suf- ficiently well developed that the effects of excess water are reduced. As population increased, grain yield in the March planting increased from 106 to 132 bushels per acre. A range of 74 to 97 bushels per acre was obtained in the April planting; however, no increase was observed between 20,000 and 25,000 plants per acre. The effect of plant populations and bed height on root development is shown in Figure 9. A negative linear correlation was obtained be- tween plant population and dry weight of roots per plant. However, the total dry weight of corn roots produced per acre increased as the pop- ulation increased to 20,000 plants. In general, the dry weight of roots and width of the root clump was less affected by bed height than was the depth and angle of root penetration. A curvilinear effect was ob- tained between bed height and the dry weight of roots and width of root clump. A linear effect between depth of root clump penetration and bed height was indicated. (A. J. Norden.) Evaluation of Ronphagrass for Pasture in Florida.-Ronphagrass, a perennial bunch type grass, produced less forage than adapted varieties of rye and oats but outyielded wheat during winter trials at Gainesville. Ronphagrass continued to produce fresh green forage in the late spring, when cereal grains matured, but it became dormant during the sum- Florida Agricultural Experiment Stations mer. Ronphagrass tolerated frosts which seriously injured the leaves of cereal grains. Ronphagrass contained a high crude protein content (24.5 percent of the dry forage). Ronphagrass was less palatable than cereal grains to beef cattle; however, they would eat it when other forages were not available. Ronphagrass was toxic to sheep. Seventeen days after initial feeding of pure ronphagrass to a sheep, the animal became extremely nervous, as evidenced by trembling, showed abnormal coordination and eventu- ally died. There was no recovery in afflicted animals even after they were fed normal diets for 2 months. Figure 9.-Representative root clumps of Florida 200 hybrid corn grown on 9-inch beds (upper photograph) and 0-inch beds (lower photograph). Root clumps on the left in each photograph are from plots having 25,000 plants per acre, and clumps on the right are from plots with 5,000 plants per acre. Annual Report, 1961 67 Exploratory experiments indicated that high nitrogen content in the grass was not the principal cause of the disorder. A high level of avail- able cobalt (25 times the daily requirement) administered orally, daily, in capsules, prevented the disorder. A comparable high level of zinc (administered orally), intramuscular injections of Vitamin B., or a co- balt bullet in the rumen did not prevent the disorder. (0. C. Ruelke' P. E. Loggins', J. T. McCall9, C. B. Ammerman' and C. F. Simpson."o) 8 Agronomy Department. 9Animal Science Department. 1o Veterinary Science Department. Florida Agricultural Experiment Stations ANIMAL SCIENCE Research was conducted on 55 projects. New projects include studies on age at which to first breed heifers; geographical and selection effects on early lambing; mineral requirements of cattle; effect of nutrient de- ficiencies on semen production of cattle and rams; effect of pre-slaugh- ter feeding of sucrose to swine on carcass quality; the effect of tem- perature on litter size in gilts and on vitamin A need of swine, sheep and cattle; the effect of flavoring agents in swine rations; the effect of level of nutrition on life span of rats; the effect of method of processing on the nutritive value of corn; and the evaluation of ronphagrass for feeding cattle and sheep. A beef cattle shed was constructed for animal breeding and physiology studies. Holding pens for handling animals prior to slaughter were con- structed outside the Meats Laboratory. A small addition was made to a barn at the Nutrition Laboratory for digestion trial studies. Grant-in-aid funds totaling approximately $110,000 were obtained from 21 different commercial companies, foundations and the U.S. Public Health Service. These funds made it possible to expand many of the research studies in the department. The department has continued its cooperation with many other de- partments and branch stations in nutrition, physiology, breeding, genetics and meat studies. Many of our staff have also judged livestock shows and helped breeders in Central and South America with their livestock procurement and production problems. The department receives consid- erable foreign correspondence, and persons from all parts of the world visit and consult with our staff frequently throughout the year. Some of the staff have visited Venezuela and have advised and consulted with Central University and the University of Zulia on their animal science teaching and research work. This program has been sponsored and fi- nanced by the Creole Oil Foundation of Venezuela. At the present, 7 Latin American students are doing research and graduate study toward advanced degrees in the department. This is indicative of the increas- ing importance of Florida in the Latin American area. MINERAL REQUIREMENTS OF CATTLE1 Hatch Project 133 C. B. Ammerman, R. L. Shirley, L. R. Arrington, J. P. Feaster and G. K. Davis Forty-eight heifers were divided equally into 4 ration groups and win- tered on fair Bahiagrass pastures for 135 days before being placed in the feedlot for 143 days. Groups 1, 2, 3 and 4 were fed during wintering 1.07, 1.31, 1.57 and 1.80 pounds of cottonseed meal and 1.61, 2.08, 3.12 and 5.61 pounds of citrus pulp per day, respectively. Average daily gains during the wintering period for the 4 groups were 0.16, 0.32, 0.56 and 1.04 pounds, respectively. When the heifers were sacrificed after being in the feedlot, the gracilis muscle, heart ventricle and liver were found to contain 194+ 4, 236+- 6 and 399- 2 milligrams of phosphorus per 100 grams of fresh tissue, respectively. Corresponding values for per- centages of total solids in the muscle, heart and liver were 26.7 1.5, 22.0- 0.3, and 30.3 2.6, respectively. SIn cooperation with W. G. Kirk, F. M. Peacock and E. M. Hodges, Range Cattle Station; H. L. Chapman, Everglades Station; W. C. Burns, West Central Florida Station; and R. B. Becker and J. M. Wing, Dairy Science Department. Annual Report, 1961 Semen samples from bulls that received the National Research Coun- cil recommended level of dietary protein were pooled, and 445 minutes were required for methylene blue reduction compared to 140 minutes re- quired for corresponding semen from bulls that received 9 percent of this protein level. Aluminum, calcium and adenesine triphosphate were found to have no effect on rate of reduction of the methylene blue, while ferrous iron increased the rate by 25 percent in both dietary groups, and copper (2.6 ppm) completely inhibited reduction in all sam- ples. This project is closed with this report. INVESTIGATION OF MINERAL NUTRITION PROBLEMS OF LIVESTOCK THROUGH THE USE OF LABORATORY ANIMALS Hatch Project 346 R. L. Shirley, J. T. McCall, L. R. Arrington, C. B. Ammerman and G. K. Davis Over a period of 7 weeks young rats were found not to be affected by the dietary protein (17.5 versus 10 percent) level on the deposition of zinc and copper in the liver. Diets that contained 1,000 ppm of copper, both with and without 200 ppm of molybdenum, resulted in about 2 times as much zinc deposited in the liver as the controls. The low protein group deposited about 2 times as much iron in the liver as the high protein group; this was also true in rats that received 1,000 ppm of copper. However, rats that received 200 ppm of molybdenum plus 1,000 ppm of copper had only about half as much iron in the liver in the 10 percent compared to the 17.5 percent dietary protein groups. This inter- ference of molybdenum with iron deposition occurred only in the pres- ence of high levels of copper. A diet that contained 1,000 ppm compared to 6 ppm of copper resulted in about 10 times as much copper being pres- ent in the liver. Approximately 3 times as much (P<0.05) orally admin- istered radioactive copper-64 was deposited in the livers of the rats fed 1,000 ppm of copper and 200 ppm of molybdenum and 10 percent protein diets compared to corresponding rats that were fed 17.5 percent pro- tein. The 17.5 percent protein diet gave an increase in hemoglobin over the 10 percent protein diet; the 200 ppm of molybdenum decreased he- moglobin; and 1,000 ppm of copper increased the hemoglobin (P <0.01). This project is closed with this report. HERBAGE COMPOSITION AND ANIMAL RESPONSE AS INFLUENCED BY PASTURE MANAGEMENT2 Hatch Project 356 R. L. Shirley, J. T. McCall, P. E. Loggins, J. F. Hentges, J. F. Easley and G. K. Davis Much of the analytical work in the Animal Nutrition Laboratory is con- cerned with this project, and it involves cooperative work with many of the branch stations. Over 3,300 determinations were made of the chem- ical composition of grasses, silages and other feedstuffs during the past year. These data have demonstrated that many factors control the ni- trate, protein, ether extract, crude fiber and ash composition of millet, Bahia, Ronpha and Pangola grasses and silages. Cooperative with W. G. Kirk, E. M. Hodges and J. McCaleb, Range Cattle Station; R. B. Becker and J. M. Wing, Dairy Science Department; and G. B. Killinger and 0. C. Ruelke, Agronomy Department. Florida Agricultural Experiment Stations TRANSFER OF MINERAL ELEMENTS THROUGH THE PLACENTA AND THEIR DISTRIBUTION IN THE FETUS Hatch Project 566 J. P. Feaster and R. L. Shirley Findings obtained on the placental transfer of radioactive iron (Fe-59) in the rat following intramuscular injection indicate that iron crosses the placenta as early as the thirteenth day of the 22-day gestation period, and that the amount transferred increases with increasing fetal age. Average percentage of the Fe-59 dose found in each 16-day fetus, 48 hours after injection into the maternal rat, was about 0.3 percent, while 4.8 percent was found in each 22-day-old fetus. Thus, iron transfer at the end of pregnancy was about 16 times as high as that just past mid- pregnancy. In terms of concentration of radioiron in the fetus, or per- cent of the dose per gram of fetus, a peak was reached on the seventeenth day with a gradual decline in concentration noted to term. This project is closed with this report. PASTURE PROGRAMS AND BREEDING SYSTEMS FOR BEEF PRODUCTION IN FLATWOOD SOILS OF CENTRAL AND NORTH CENTRAL FLORIDA State Project 627 M. Koger Five pasture programs are being evaluated by grazing with cows and calves which are also utilized in the cattle breeding study. The 5 pasture programs include (1) an all-grass program fertilized at the rate of 450 pounds of 0-10-10 plus 180 pounds of nitrogen annually per acre. The remaining programs are clover-grass, fertilized at vary- ing rates as follows: (2) 300 pounds of 0-10-20; (3) 500 pounds of 0-10-20 annually plus nitrogen as needed up to 60 pounds per acre; (4) 700 pounds of 0-10-20 plus nitrogen as needed; and (5) 900 pounds of 0-10-20 plus nitrogen as needed on irrigated pasture. The weight of calf weaned per acre was 285, 316, 304, 304 and 312 pounds respectively. The breeding systems being compared are (1) straight breeding to An- gus and Hereford, (2) crisscrossing of Angus and Hereford, (3) criss- crossing Angus and Brahman and (4) crisscrossing Hereford and Santa Gertrudis. Weaning rate in 1960, based on number of cows bred, was 83, 90, 80 and 84 percent respectively. Average weaning weight per calf was 449, 427, 443 and 465 pounds for the respective groups. (See also Project 627 under Agricultural Economics, Agricultural Engi- neering, Agronomy and Soils for other phases of this cooperative study). SELECTION OF CATTLE FOR BEEF PRODUCTION IN SOUTHEASTERN UNITED STATES State Project 629 M. Koger, A. Z. Palmer (Contributing to S-10) and A. C. Warnick This project is cooperative between the Florida Station and USDA. It is located at Brooksville, and results are reported under Project 629 un- der West Central Florida Experiment Station. EFFECT OF PROTEIN SUPPLEMENTATION OF PASTURE FORAGE UPON FERTILITY IN BEEF CATTLE State Project 710 A. C. Warnick, M. Koger and T. J. Cunha Twenty-four 3-year old pregnant Brahman x Angus heifers weighing approximately 770 pounds were individually fed 1 of the following ra- Annual Report, 1961 71 tions: (1) 100 percent N.R.C. requirements without alfalfa, (2) 120 per- cent N.R.C. requirements without alfalfa and (3) 120 percent N.R.C. re- quirements including 6 pounds alfalfa meal. The heifers on the 100 per- cent ration lost 25 pounds, while heifers on the 2 120 percent rations gained approximately 58 pounds 120 days following calving. The average calf gains on the 3 rations were similar, ranging from 164 to 171 pounds during the 120-day period. The percentage of heifers showing estrus and average interval in days from calving to first estrus on the 3 rations was (1) 38 percent, 93; (2) 62 percent, 87; and (3) 88 percent, 71. The production of heifers raised during their first 2 years on the 4 winter programs, (1) grass pasture, low protein; (2) grass pasture, high protein; (3) clover-grass pasture, low protein; and (4) clover-grass pas- ture, high protein, has been compared. Heifers on the high protein sup- plement averaged 35 pounds heavier after the first winter than those on the low protein and at 30 months of age those on high protein were 41 pounds heavier. However, heifers raised on the clover-grass pastures were 103 pounds heavier at 30 months of age than comparable heifers raised on the straight grass pastures. There was a 4 percent advantage in calves weaned for heifers wintered on high protein compared to low protein, while heifers raised on clover weaned 10 percent more calves than heifers on the straight grass pasture. The average weaning weight of calves per cow was 19 pounds heavier in females wintered on high protein compared to low protein and 39 pounds heavier for those win- tered on clover-grass compared to those on straight grass pasture. This project is closed with this report. HERITABILITY OF PERFORMANCE ESTIMATES ON ABERDEEN ANGUS, BRAHMAN AND HEREFORD CATTLE State Project 717 J. F. Hentges, Jr., and M. Koger Relative breed performance data were compiled on registered Angus, Brahman and Hereford cattle and calves which were maintained under similar environmental conditions. These data will be collected for a 10- year period to permit calculation of heritability estimates of perform- ance factors. For the first time, average birth weights of Angus calves equalled those of other breeds. Apparently the effect of the imported Angus herdsire, Elector of Shempston, was reflected in the improved performance of this calf crop. Prior to supplemental feeding, Angus calves of each sex group gained faster than Herefords. During the sup- plemental feeding period, Angus males out-gained Hereford males by 0.47 pound per day while Angus females gained 0.24 pound per day faster than Hereford females. Non-creep-fed Brahman male and female calves each had average daily gains of 1.7 pounds. For the first time, every Brahman female 3 years of age or older gave birth to a calf. The re- production rate in the Angus herd was reduced 16 percent by initiation of artificial insemination. Type scores and estimated slaughter grades were higher for Angus and Hereford than Brahman offspring. Detailed data on other performance factors were recorded for later analyses. NUTRITIONAL REQUIREMENTS OF PIGS WEANED AT AN EARLY AGE Hatch Poject 738 G. E. Combs, H. D. Wallace and T. J. Cunha A study designed to determine the phosphorus requirement and op- timum calcium to phosphorus ratio for young pigs has been completed. Florida Agricultural Experiment Stations The pigs were weaned at 2 weeks of age and were individually fed semi- purified or fortified corn-soybean rations respectively until they were 35 or 155 days of age. Criteria used in establishing the optimum require- ment and ratio were weight gain, feed efficiency, percentage ash and radiographs of the fibula and femur and length of the femur. An evalua- tion of all criteria indicated that the phosphorus requirement of pigs from 2 to 7 weeks of age was 0.44 percent of the ration and that with this phosphorus level the optimum calcium to phosphorus ratio was 0.9:1. From 35 to approximately 155 days of age 0.44 percent phosphorus with a calcium to phosphorus ratio of 1.2:1 was adequate for optimum growth and skeletal development. Pigs weaned at 2 weeks of age were fed rations containing soybean meal, fish meal, peanut meal or dried skim milk as the source of sup- plementary protein. The daily gains and feed efficiencies ranked in de- creasing order for the various rations were as follows: dried skim milk, soybean meal, fish meal and peanut meal. Digestion coefficients for dry matter, protein, ash, ether extract and energy are presently being de- termined for the various rations. These coefficients will permit the pig's digestive ability to be evaluated at 3, 5 and 7 weeks of age. The influence of the calcium to phosphorus ratio on pig performance and nutrient digestibility is presently being studied. PRODUCTION OF EARLY SPRING LAMBS IN FLORIDA Hatch Project 740 P. E. Loggins, M. Koger, (Regional Project S-29) A. C. Warnick and T. J. Cunha The 1961 lamb crop was produced from a straight breeding program of Rambouillet and Florida native ewes. Forty-seven Rambouillet ewes (17 of which came from the Auburn, Alabama, early-lambing ewe flock) and 39 Florida native ewes were exposed to rams of the same breeding. Visectomized rams were used from April 15 to Septemebr 15, 1960, to determine earliness of estrus and breeding dates. Intact rams were placed with the ewe flock beginning July 1 for a 75-day breeding sea- son. The Florida Station Rambouillet, Florida native and Auburn Ram- bouillet ewes were found to be in anestrus prior to July 1. The average dates of first estrus in the breeding ewes were as follows: Florida Ram- bouillet, July 29; Auburn Rambouillet, July 19; and Florida native, July 31. The lambing percentages for the 1961 lambing season were as fol- lows: Rambouillet, 98 percent and Florida Natives 115 percent, with aver- age lambing dates of December 30 and December 30 respectively. The lambs were weaned on March 9, 1961, at an average age of 69 days. The lambs received creep feed and were continued on a full feed- ing program following weaning until May 19, 1961. The lambs averaged 67 pounds at 139 days average age on May 19 and graded a low Choice. The Rambouillet lambs averaged 70 pounds and graded Choice. The Florida native lambs averaged 64 pounds and graded Good plus. This project is terminated with this report. GENETICS OF DWARFISM IN BEEF CATTLE State Project 752 M. Koger, A. C. Warnick (Contributing to S-10) and J. F. Hentges, Jr. This year's matings concluded critical test matings of the Snorter Hereford, Midget Brahman and Guinea (Dexter). The results from the previous years' matings confirm previous findings: (1) a high frequency of dwarf genes results in numerous resorbed fetuses, abortions and still- Annual Report, 1961 73 births among normal appearing calves; (2) mating of carriers of the Dexter gene (Guinea) with known carriers of the Snorter gene has re- sulted in 1 observed Dexter type "bulldog monster" plus numerous re- sorbtions; and (3) mating of Snorter dwarf bulls to known carrier fe- males of mixed breeding has produced less than 1/ dwarf progeny which would be expected on the basis of a simple Mendelian recessive. Cooperative work with the Medical School established that the Snorter dwarf excretes in the urine an acid Mucopolysaccharide similar or iden- tical to chondroitin sulphuric acid-B, the same polysaccharide found in the urine of humans affected with a form of dwarfism known as the Hurler syndrone or gargoylism. These forms of dwarfism in the 2 spe- cies show other phenotypic similarities also. Work on excretion of this polysaccharide by carrier and non-carrier cattle continues. NUTRITIONAL AVAILABILITY OF COMPONENTS OF LIVESTOCK FEEDSTUFFS Hatch 755 L. R. Arrington and C. B. Ammerman Digestion trials were conducted with steers to determine the digestibil- ity of nutrient components of dried citrus pulp and to study the effect of excess calcium upon digestibility of these components. When citrus pulp composed 70 percent of the ration, the protein digestibility of 55 percent and crude fiber digestibility of 60 percent in normal pulp were not af- fected by an increase in the calcium from 1.5 to 3.1 percent. Digestibil- ity of ether extract and nitrogen free extract, however, were significant- ly depressed. A slight but non-significant decrease in energy digestibil- ity occurred when the calcium intake was 3.1 percent. Digestion coefficients of the nutrients in dehydrated tomato pulp when fed alone to steers were protein, 54.6; ether extract, 85.5; fiber, 42.2; and nitrogen free extract, 78.4. Digestibility of the nutrients was im- proved when the tomato pulp was fed with soybean oil meal. Nitrogen balance data obtained with lambs fed tomato pulp revealed a biological value of 57, which may be compared with a value of 64 for soybean oil meal obtained in the same manner. The apparent digestibility of the nitrogen in tomato pulp by lambs was 51 percent. NUTRITIONAL REQUIREMENTS OF RABBITS State Project 768 L. R. Arrington, C. B. Ammerman and G. K. Davis The effect of protein intake upon the growth of young rabbits was studied with Dutch and New Zealand rabbits. Using rations containing 11.5, 13.5 and 15.5 percent protein, 4-week old Dutch rabbits gained 463, 550 and 589 grams respectively during a 28-day experimental period. At 8 weeks of age, the intake of 13.5 percent protein improved gains over 11.5 percent, but 15.5 percent protein did not increase the gain over 13.5 percent. Using additional rations containing 16, 20 and 24 percent pro- tein fed to 8-week old rabbits, the weight gains were not improved in Dutch rabbits as protein increased, but were slightly improved in New Zealand rabbits fed the same rations. Feed efficiency was not improved with increasing intakes of protein. Feed conversion by growing rabbits decreased rapidly with increas- ing age. At 4 to 8 weeks of age, the feed required per unit of gain was 2.6; at 8 to 12 weeks, 4.4; and at 12 to 16 weeks, 6.5. The growing New Zealand rabbits were more efficient in the conversion of feed than were Florida Agricultural Experiment Stations Dutch rabbits. At 8 to 12 weeks of age, the feed efficiency of New Zealands was 3.95, and the Dutch, 4.82. The feeding of a ground ration reduced the voluntary feed intake of rabbits by 11 percent when compared to the intake of the same ration fed in pellet form. Fecal dry matter excretion was determined in mature rabbits fed dif- ferent intakes of feed in effort to measure the effect of intake upon coprophagy. Feed intakes amounting to 1.6, 3.0, 3.25 and 5.0 percent of body weight resulted in dry matter excretion equal to 29.39, 32.25, 32.69 and 33.84 percent of the intake. These results indicate that at the lower feed intakes a greater proportion of feces is consumed in the normal practice of coprophagy. INFLUENCE OF NUTRITION, BREED, AGE, AND SEX ON RESPIRATORY ENZYMES IN THE TISSUES OF CATTLE, SWINE AND SHEEP3 State Project 805 R. L. Shirley, G. K. Davis, H. D. Wallace, A. C. Warnick, J. F. Hentges, A. Z. Palmer, P. E. Loggins, J. W. Carpenter and T. J. Cunha A ration that contained approximately 9 percent of the N.R.C. recom- mended level of dietary protein was observed to decrease (P<0.01) the mg. of nitrogen per ml. of semen from 1.85 (for control adequate protein fed bulls) to 0.95, to decrease (P<0.01) the ig. of phosphorus liberated per ml. semen from 492 to 61, and to decrease the Ag. of phosphorus liberated per mg. nitrogen in the semen from 306 to 57 due to 5-nucleotidase ac- tivity, respectively. Rams fed urea as the only source of nitrogen com- pared to others fed Dracket soybean protein had 105 compared to 280 lig. phosphorus liberated per mg. nitrogen in the semen due to 5-nucleo- tidase activity (P<0.01). The bulls fed an adequate level of protein had approximately 400 mg. compared to 10 mg. of fructose per 100 ml. of semen in the group on only 9 percent N.R.C. protein requirements. Yet, when fructose was added to the semen of both groups of bulls the adequate protein group had only slightly greater capacity to produce fructolysis. Rams that received urea as their only source of nitrogen had greater (P<0.01) fructolysis than those that received Dracket protein or no nitrogen at all over a 7-week period. The rate of methylene blue reduction in bull semen was found to be significantly increased in the semen of the bulls fed the recommended protein level and in the rams that received the Dracket protein. The rate of decoloration was significantly increased in the bull semen when succinate, glutathione and thioglycollic acid were added. THE EFFECT OF HORMONES ON THE PHYSIOLOGY OF REPRODUCTION IN BRITISH AND BRAHMAN BEEF CATTLE Hatch Project 809 A. C. Warnick and M. Koger Time of estrus and ovulation were controlled in nonparous cycling Brahman heifers injected with 75 mg. progesterone every third day for 15 days. The subsequent estrous cycle ranged from 18 to 23 days in length. A second series of injections of progesterone in the same heifers did not inhibit estrus and ovulation, indicating a possible refractory re- sponse to steroids or dosages near the threshold level. Time of estrus 3 Cooperative with W. G. Kirk and F. M. Peacock, Range Cattle Station. Annual Report, 1961 was regulated in a purebred herd of 94 Brahman females with daily injections of 25 mg. progesterone for 14 days followed with one injection of 2 mg. estradiol benzoate. However, only 5 percent of the females became pregnant when inseminated with frozen semen on the third and fourth days following last injection of progesterone. One-third of the 2- year old heifers and 1/ of the parous cows failed to ovulate following treatment. The specific cause of low fertility at the induced estrus is not known but appears to be one of failure of ovulation, failure of fertili- zation or embryonic mortality. Daily injections of 25 mg. progesterone or injections every third day of 75 mg. progesterone over a 15-day interval were equally effective in regulating estrus with purebred Angus, Hereford and Brahman females. The pregnancy rate following artificial insemination in the above ex- periment was Angus, 21 percent; Brahman, 40 percent; and Hereford, 12 percent. THE INFLUENCE OF DIETARY PROTEIN LEVFL ON PHYSIOLOGICAL PHENOMENA IN BEEF CATTLE State Project 867 J. F. Hentges, Jr., A. C. Warnick and R. L. Shirley The study of the comparative physiology of Brahman and Hereford cattle fed 2 levels of dietary protein was terminated with several scientif- ic publications. Brahman venous blood was reported to contain a higher percentage saturation with oxygen and a lower percentage of carbon dioxide than Hereford venous blood. The erythrocytes in Brahman blood were shown to have a lower potassium and higher sodium content than those in Hereford blood. In a study of adrenal gland weights from 119 cattle of all sexes, it was noted that Brahmans in all sex groups had a slightly smaller adrenal to live weight ratio than Herefords. The total adrenal weight of cattle was reported to be smaller in relation to unit body weight than any other mammalian species for which data are avail- able. The thyroidal uptake of radioactive iodine was reported to be slow- er in Brahmans than Herefords. Hereford thyroids took up more iodine and retained a greater percentage of it at comparable time intervals than Brahmans. These data confirmed a belief that Herefords have a more active thyroid than Brahmans. A 50 percent reduction in dietary protein intake reduced the iodine retained by the thyroids of both spe- cies. In a series of 20 digestion trials, Brahmans digested crude protein and other nutrients more efficiently and consumed more feed dry mat- ter at low levels of nutrition than Herefords, but no differences in di- gestibility were apparent when nutrition level was adequate. These find- ings further explain the ability of Brahman cattle to better withstand un- favorable semi-tropical environments. FACTORS AFFECTING SLAUGHTER AND CARCASS GRADES OF BEEF CATTLE State Project 884 A. Z. Palmer In 1957, 48 weanling heifers of mixed breeding but predominately Brahman and Shorthorn crosses were grouped into 4 lots by weight and breeding. Wintering and feed lot phases of the study of the "Effects of Winter Gain of Calves on Feed Lot Performance and Carcass Grade" were conducted at the Range Cattle Station, Ona. The trial was replicat- ed in 1958, 1959 and 1960. Heifers on the first 3 trials were slaughtered at the University Meats Laboratory, and slaughter and carcass data Florida Agricultural Experiment Stations were recorded. Fourth trial heifers were slaughtered during July 1961. Data collected over the 4-year period are being statistically analyzed. (See also Project 884, Range Cattle Station.) EFFECT OF GAMMA RADIATION OF THE PREGNANT FEMALE ON REPRODUCTION State Project 906 J. P. Feaster To test the effect of whole-body radiation on fetal nutrition, as meas- ured by the placental transfer of iron to the fetus, pregnant female rats were exposed to 200 roentgens whole-body cobalt-60 radiation. Forty- eight hours later they were given single intramuscular injections of ra- dioiron (Fe-59), and 48 hours after dosing the fetuses were removed and assayed for Fe-59 content. Rats were irradiated at stages of gestation ranging from the twelfth to the eighteenth day. Controls consisted of pregnant rats in which injection of Fe-59 was not preceded by Co-60 irradiation. Content of Fe-59 in fetuses from the 2 lots of rats was compared. Radioiron was found to cross the placenta in both lots of rats at all stages of gestation studied, from the thirteenth to the twenty-second day, or term. Rate of transfer of radioiron was clearly higher in the ir- radiated rats than in controls, indicating increased placental permeabil- ity with irradiation. Radiation did not affect the excretion of Fe-59 by the adult rats, the amounts excreted in 48 hours by both lots being negligible. Amounts of radioiron found in blood, liver and muscle were also similar for rats of the control and irradiated lots. To study the intra-uterine buildup of proteins, whole fetuses obtained under this project have been hydrolyzed to free the amino acids, which are being measured both qualitatively and quantitatively after isolation by column chromatography. Analyses completed indicate that all amino acids of biological significance are present in the rat fetus by the eigh- teenth day. This project is closed with this report. ANGUS, BRANGUS, AND ANGUS X BRANGUS CROSSBREDS FOR BEEF PRODUCTION IN THE EVERGLADES State Project 922 M. Koger This is a new project cooperative with the Glades State Prison Farm and the Everglades Station. The first year's calf crop will be weaned in 1961. (See also Project 922, Everglades Experiment Station.) THE EFFECT OF A CONTROLLED TEMPERATURE ON REPRODUCTION IN BRAHMAN CATTLE Hatch Project 938 A. C. Warnick and M. Koger Observations were made on ovarian development in Brahman and other breeds of beef cattle. Studies in a private purebred Brahman herd and at the West Central Experiment Station at Brooksville indicate that from 50 to 75 percent of the 2-year old heifers do not have a corpus luteum at the beginning of the breeding season. Also, 67 to 80 percent of the lactating and non-lactating parous cows, respectively, had no cor- pus luteum at the beginning of the breeding season. All 2-year old heifers of the Angus, Hereford, Brangus and Santa Gertrudis at the Annual Report, 1961 77 station in Brooksville had a corpus luteum at the beginning of the breed- ing season. The lack of ovarian development as shown by no corpus luteum in Brahman females would partially explain lowered reproduction rate and late calving compared to British breeds. Some 3-year old nonparous Brahman heifers show irregular estrual cycles and long periods of an- estrous and anovulation during the summer. There was a tendency for heifers showing irregular estrual cycles during the summer to repeat this condition in the winter. It is possible that regularity of the estrous cycle in Brahman is a heritable trait and improvement in reproductive rate could be made by selection for it. The age at puberty is delayed in Brahman heifers compared to Shorthorn or Brahman x Shorthorn heifers raised under a similar environment. EFFECT OF NITROGEN FERTILIZER LEVELS WITH AND WITHOUT A COMPLETE MINOR ELEMENT MIXTURE ON THE YIELD, CHEMICAL COMPOSITION AND DIGESTIBLE NUTRIENT CONTENT OF COASTAL BERMUDAGRASS HAY State Project 972 J. F. Hentges, Jr. Hays for cattle feeding experiments were produced by 4 fertilizer treatments on Coastal bermudagrass. The fertilizer treatments were a base application of 0-10-20 with and without minor elements plus either 100 or 200 pounds nitrogen per acre initially with 1z this amount ap- plied after each cutting for hay. Minor element application increased the yield of hay 1,483 pounds for a 4-cutting season yield of 8,931 pounds per acre with the 100 pound nitrogen per acre fertilizer treatment. With the 200 pound per acre nitrogen level, minor elements increased the yield 822 pounds for a season yield of 11,683 pounds per acre. Increasing the level of nitrogen fertilization from 100 to 200 pounds per acre in- creased the 4-cutting season yield of hay by an average of 3,082 pounds per acre. Crude protein content of hay was increased by increments of 2 percent to 5 percent by increasing the rate of nitrogen fertilizer from 100 to 200 pounds per acre. The average crude protein content of all hay was 9.2 percent and 12.2 percent for 100 and 200 pound nitrogen treatments respectively. The digestibility of crude protein, dry matter and energy increased with increases in hay protein content. Grinding and/or pelleting did not affect the digestibility of dry matter or the total digestible nutrient content but decreased protein and crude fiber digesti- bility. Lactating cows given free access to either long or ground Coastal bermudagrass hays grown with either the 100 or 200 pound nitrogen fer- tilizer rates lost 0.6 to 0.7 pound weight per day; however, calves suck- ling these cows gained from 0.7 to 1.0 pound per day. Lactating cows fed hay fertilized with 200 pounds nitrogen per acre and ground through a /4-inch screen lost less weight, produced heavier calves and consumed more dry matter than cows fed a similar hay in the long form. (See also Project 972, Suwannee Valley Station.) FACTORS INFLUENCING BEEF TENDERNESS' Hatch 975 A. Z. Palmer, J. W. Carpenter, M. Koger and R. L. Shirley Twenty-two steers of mixed breeding, averaging 1,067 pounds live weight, grading U.S. Good, were randomly divided into control and treat- Cooperative with W. G. Kirk and F. M. Peacock, Range Cattle Station. Florida Agricultural Experiment Stations ed groups. The treated cattle were injected with 500 ml. of a saturated NaC1 solution 30 minutes ante-mortem to determine the effect of that treatment on beef tenderness. It was found that the injection caused an increased incidence of carcasses lacking a desirable bright cherry-red color of lean; the injection did not influence the tenderness of broiled short-loin steaks. In a second study, involving 80 cattle divided into 5 lots of 16 head each, ante-mortem injections of 0.9 percent NaCI (.07 ml. per pound live weight), crude papain ash (0.2 mg./lb. live weight), crystalline papain (0.2 mg./lb. live weight) and crude papain ash (0.2 mg./lb. live weight) plus crystalline papain (0.2 mg./lb. live weight) had no effect on beef tenderness. The latter 2 treatments, however, over-tenderized the livers. The purpose of a third study was to accomplish the technique of sur- gically blocking the blood supply to 1 hind leg of anesthetized sheep while injecting tenderizing materials in the juglar vein to tenderize the leg with a blood supply. The technique was developed and shown to offer excellent possibilities as a method to use in studying the effects of vari- ous ante-mortem injections on tenderness. MANAGEMENT AND COST FACTORS RELATED TO MULTIPLE FARROWING Hatch Project 977 H. D. Wallace, G. E. Combs and M. Koger5 A new farrowing facility was completed and used for the first time in August 1960. At this time 18 sows farrowed an average of 9.06 live pigs and weaned an average of 7.94. Comparable figures for the next farrow- ing involving 21 sows during the month of October 1961 were 9.09 and 8.00. In January 1961, 15 sows farrowed an average of 9.93 live pigs and weaned 8.87. The March 1961 farrow for 28 sows resulted in an average of 9.39 live pigs per sow with an average survival of 9.09. These data suggest a gradual improvement in farrowing results over the period from August to March. This improvement probably reflects the ever increasing number of crossbred sows (Duroc X Landrace) in the herd. Thirty-six litters from crossbred sows show an average of 9.69 live pigs per litter with a 94.8 percent survival to weaning. Twenty comparable purebred Duroc litters produced an average of 8.45 live pigs with 90.5 percent survival to weaning. Thus far data collected do not show great seasonal influences either in terms of regularity of estrous, conception rate or sow performance at farrowing and during lactation. A compari- son of the number of matings per conception (1 versus 2) indicates a difference in favor of 2 matings of almost 1 pig per litter weaned. Data are being accumulated on the influence of age of pigs at weaning on subsequent rebreeding efficiency of the sows. A nutritional study which is evaluating corn dried distillers solubles as a source of unidentified factors has not yielded positive results to date. Performance and car- cass quality data for market swine are accumulating for 3 breed groups Purebred Durocs, Durocs X Landrace and a 3-way cross consisting of 1/ Duroc, 14 Landrace and %/ Hampshire. The first phase of the cost analysis will be initiated as soon as 1 year of the study has been com- pleted. 6 Cooperative with W. K. McPherson, Agricultural Economics Department, T. C. Skinner, Agricultural Engineering Department, and S. J. Folks, Florida Power Corporation. Annual Report, 1961 EVALUATION OF FINISHING METHODS WITH STEERS FROM DIFFERENT BREEDING SYSTEMS State Project 981 M. Koger, T. J. Cunha and A. Z. Palmer The second year's results from a 3-year study have been completed. One more year's data will be included before the data are summarized. AGE OF HEIFERS AT FIRST BREEDING AS RELATED TO BEEF PRODUCTION State Project 995 M. Koger and A. C. Warnick Since 1958, 12 of the replacement heifers at the Beef Research Unit have been bred as yearlings to calve first at 2 years of age. Calves from these 2-year-old heifers are being vealed at the start of the breed- ing season on March 1. The other half of replacements have been bred to calve first at 3 years of age. The first year's data from the first group of heifers will not be complete until the fall of 1961. FLORIDA FEEDS AND BY-PRODUCTS FOR SWINE FEEDING State Project 999 G. E. Combs and H. D. Wallace Three experiments have been conducted with early weaned pigs to evaluate the usage of 55 percent protein peanut meal in starter and grower rations. The peanut meal proved unsatisfactory when used as the only source of supplemental protein. When the peanut meal was supplemented with lysine or lysine and methionine, performance was not significantly improved. With a different sample of peanut meal, supple- ments of lysine or lysine and threonine appeared beneficial. When pea- nut meal was used in combination with soybean meal, the most satis- factory performance was obtained with a mixture in which peanut meal and soybean meal contributed 25 percent and 75 percent respectively of the supplemental protein. In another study the feasibility of substituting ground snapped corn for corn meal was investigated. The results showed that substituting the snapped corn for corn meal adversely affected both rate and effi- ciency of gain. However, the increase in carcass value obtained by re- stricting the feeding of snapped corn to the period from 100 pounds to market weight was sufficient to offset this inferior growth performance. Feeding of the ground snapped corn throughout the growing-finishing pe- riod was not found to be an economical practice. The data from another experiment indicated that fish meal could serve satisfactorily as the only source of supplemental protein for fin- ishing swine. EFFECT OF CULTURAL PRACTICES UPON THE YIELD AND DIGESTIBLE NUTRIENT CONTENT OF CORN FOR SILAGE State Project 1000 J. F. Hentges, Jr., and J. T. McCall Silage for beef cattle feeding studies was produced from Dixie 18 corn grown with varying fertilizer treatments and plant populations. In- creasing the plant population from 6,750 to 13,500 plants per acre in- creased forage yields but decreased nutrient content (percent) and di- gestibility. Within each plant population, an increase in fertilizer rate from 56-48-48 to 112-96-96 pounds N-P-K per acre increased protein con- Florida Agricultural Experiment Stations tent; had little effect on crude fiber, ether extract or energy; and de- creased nitrogen-free extract and ash. In the highest plant population and lowest fertilizer rate, protein digestibility was highly significantly lower than in other treatment combinations. Digestibility of protein, en- ergy and ether extract were significantly increased in the high fertilizer treatments. Increasing the fertilization rate at both plant populations increased total nutrients by an average of 1,107 pounds per acre or 25 percent and total digestible nutrients by an average of 903 pounds per acre or 27.5 percent. Increasing the plant population from 6,750 to 13,500 increased total nutrients by 1,511 pounds per acre or 32.6 percent and total digestible nutrients by 1,167 pounds per acre or 34.2 percent. All treatments of corn forage contained less than 0.015 percent potassium nitrate, which was far below toxic levels. (See also State Project 1000, Soils Department). LYSINE SUPPLEMENTATION OF PRACTICAL SWINE RATIONS State Project 1001 H. D. Wallace, G. E. Combs and A. Z. Palmer Two experiments have been completed this year which were primar- ily concerned with the influence of lysine supplementation on the mani- festation of gossypol toxicity in pigs fed cottonseed meal rations. The protein quality-gossypol relationship has long been a baffling problem in the cottonseed meal industry. These experiments were designed to de- termine if lysine per se would reduce or overcome gossypol toxicity. Results suggest the following summation statements. The early weaned baby pig was very sensitive to dietary gossypol and for this reason may represent a much more suitable animal for special work on the problem of gossypol poisoning than the growing-finishing pig. Increasing incre- ments of lysine supplementation (0.1, 0.2 and 0.4 percent) progressively improved both gain and feed conversion. Apparently lysine exerted most of its effect through a detoxification mechanism in counteracting gossypol poisoning. Pigs fed lysine exhibited less severe symptoms of gossypol poisoning and survival was much better, particularly at 0.4 percent and 0.8 percent levels of supplementation. Labored breathing was the most pronounced symptom of toxicosis in the live pig. Post-mortem observa- tions included hydrothorax, edema of the lungs and lesions of the heart and liver. EVALUATION OF FEED ADDITIVES IN SWINE NUTRITION State Project 1002 H. D. Wallace and G. E. Combs Several feeding experiments have been conducted to determine the efficacy of using certain antibiotics and other compounds as growth stim- ulants for growing-finishing swine. A promising new antibiotic, tylosin, has been studied extensively at various levels of supplementation. Daily gains and feed conversion were consistently improved. However, control pigs have performed very well in the trials, and the magnitude of anti- biotic response has not been as great as with other antibiotics in earlier experiments at this station. In 1 experiment in which tylosin, aureomy- cin and oleandomycin were compared, results showed a marked response to all of the antibiotics with oleandomycin producing the greatest re- sponse. An experiment planned to determine the value of feeding my- costatin, an antifungal antibiotic, in the presence of aureomycin to fungi inoculated pigs gave the following results. Oral inoculations of Candida albicans and Candida tropicalis had no apparent effect on rate of gain Annual Report, 1961 and feed utilization. Both inoculations were successfully cultured from the alimentary tract of pigs, although the culture of the latter was small. Aureomycin appeared to enhance the growth of both organisms. Mycostatin was partially effective in eliminating the Candida albicans and Candida tropicalis from the feces of the pig. In another experiment sodium acrylate was tested as a growth promoting substance with en- couraging results. Further testing of this material is planned. INHERENT BODY SIZE IN CATTLE AS RELATED TO ADAPTATION TO FLORIDA State Project 1003 M. Koger and A. C. Warnick This is a new project cooperative between the Department of Animal Science, North Florida Experiment Station and State Prison Farm, Rai- ford. Data from the first calf crop will be collected during the fall of 1961. (See also Project 1003, North Florida Experiment Station.) EFFECTS OF MODIFIED ENVIRONMENT ON THE PERFORMANCE OF GROWING-FINISHING SWINE State Project 1004 H. D. Wallace, G. E. Combs and A. C. Warnick Two experiments have been completed during the past year. The first was designed to measure humidity and temperature effects and was con- ducted during the summer months of 1960. Four groups of pigs weigh- ing approximately 65 pounds initially were subjected to different com- binations of temperature and humidity during the finishing period. The temperatures involved were 650 and 750F, and the relative humidities were 40 and 80 percent. Performance data suggested that the higher temperature and lower humidity were most desirable. Nevertheless, all groups performed quite well, indicating that none of the conditions im- posed caused any serious stress on the experimental animals. The sec- ond experiment was a large scale practical trial conducted during the winter months of 1960-61 to measure the value of providing wood shav- ings over a portion of the pens as bedding. The common practice in the operation of large confinement feeding pens is to provide no bed- ding. This study demonstrated, however, that wood shavings improved the performance of pigs, particularly during the first 4 weeks of the trial. Forty-two pigs provided with shavings gained 1.51 pounds per day and required 2.67 pounds of feed per pound gain. A similar number of pigs with no shavings gained 1.40 pounds and required 2.72 pounds of feed. Beyond 4 weeks the shavings appeared to exert very little influ- ence on performance. The tendency to develop tender-footedness was not noticeably alleviated by the use of shavings. EFFECT OF NUTRITION ON THE REPRODUCTIVE PERFORMANCE OF SWINE State Project 1010 A. C. Warnick and H. D. Wallace Forty-eight purebred Duroc gilts were assigned to 1 of 3 diets to de- termine differences in level of energy intake and alfalfa meal on puber- ty, ovulation rate, number of viable embryos at 25 days and levels of acid and alkaline phosphatase in the endometrium. The diets fed were (1) high energy with 10 percent alfalfa, (2) limited energy with 52 per- Florida Agricultural Experiment Stations cent alfalfa and (3) limited energy with 10 percent alfalfa. The average age in days and weight in pounds at puberty on the 3 diets were (1) 319, 421; (2) 348, 340; (3) 358, 392. Puberty was delayed in all gilts, probably due to a late sexual maturing strain of pigs. The average number of eggs ovulated per gilt on the 3 diets were (1) 15.6, (2) 16.1 and (3) 15.3, which means that alfalfa prevented the decrease in ovulation rate asso- ciated with limited energy. The average number of viable embryos and percent embryonic survival at 25 days based on ovulation rate on the 3 diets were (1) 12.5, 80.3 percent; (2) 14.1, 87.2 percent; and (3) 12.7, 83.4 percent. There were no significant dietary differences in alkaline and acid phosphatase activity in the endometrium, but there was significant nega- tive correlation (r = -0.351) between level of alkaline phosphatase and number of viable embryos. There were significant differences in acid and alkaline phosphatase in the endometrium due to stage of cycle and stage of gestation, indicating that hormones are probably controlling en- zyme activity of the uterus. EFFECT OF SOIL PHOSPHORUS RESIDUES ON PANGOLAGRASS PASTURES State Project 1061 R. L. Shirley This is a cooperative project between Animal Science and the Range Cattle Station. Results from this study are reported under Project 1061, Range Cattle Station. GEOGRAPHICAL AND SELECTION EFFECTS ON LAMBING DATE Hatch Project 1063 P. E. Loggins, M. Koger, A. C. Warnick and T. J. Cunha This project was just recently approved and will be initiated this summer. MINERAL REQUIREMENTS OF CATTLE Hatch Project 1079 C. B. Ammerman, L. R. Arrington, R. L. Shirley, J. P. Feaster, J. M. Wing and W. G. Kirk This project was just recently approved, and studies on mineral re- quirements of cattle are now being initiated. PRELIMINARY NON-PROJECTED STUDIES Effect of a Protein Deficiency on the Growth, Blood Constituents and Reproductive Physiology of Bulls.-Twelve weanling grade Angus bulls were studied for 7 months to determine the effect of a protein deficiency on various physiological factors. Eight bulls were fed a ration contain- ing 1.50 percent crude protein, and 4 bulls received a ration containing 13.5 percent crude protein. The deficient animals rapidly lost appetite and exhibited marked losses in body weight. During the 7 months the deficient bulls had an average daily loss of -0.71 pounds, and the controls gained 1.10 pounds daily. After 2 months on the experimental rations, the semen volume, sperm motility and sperm concentration were adversely affected in the bulls on the deficient ration. There was a constant decline in quantity and qual- ity of semen throughout the experiment from the bulls on the protein Annual Report, 1961 deficient ration. At the end of the fourth month semen was collected from all the bulls and frozen for artificial insemination. Approximately 22 heifers per bull were used in the fertility study. Conception rates are not yet available. Four of the 8 deficient bulls died by the end of the seventh month. One of these bulls became aspermia shortly before death, but the other 3 produced motile sperm in reduced amounts until they died. At this time the remaining 8 bulls were slaughtered, and samples of the reproductive tissues were obtained for histological study. At the time of slaughter, the surviving deficient bulls were still producing se- men. Average values for semen volume, motility and total sperm pro- duction for the deficient and control groups at the last collection were 2.6 and 8.9 ml., 22 percent and 61 percent and 101 X 108 and 926 X 10' respectively. Libido of the deficient bulls was markedly reduced by the deficiency. After 2 months, the bulls began to lose interest and were reluctant to mount. This decline in interest continued until the deficient bulls failed to mount at all, or would only make 1 or 2 attempts. Blood hemoglobin, hematocrit and serum protein levels were determined dur- ing the experiment. There was a gradual reduction in all 3 criteria in the deficient bulls. However, the levels did not drop far below the nor- mal range. Final average values obtained for the deficient and control groups were 7.69 and 12.44 mg per 100 ml., 36.33 and 58.68 percent and 5.43 and 6.66 percent for the hemoglobin, hematocrit and serum protein respectively. (T. J. Cunha, A. C. Warnick, J. F. Hentges, P. E. Loggins and R. L. Shirley.) Effect of Source and Level of Nitrogen on Semen Production and Libido in Rams.-Sixteen crossbred rams 11 months old and averaging 97 pounds were fed 3 rations to compare Drackett and Urea as sources of nitrogen to a nitrogen-free ration on sperm production and libido. Four of the 8 rams on the nitrogen-free ration died after an average of 78 days on the experiment but were still producing sperm cells and were able to mate a ewe at previous check before death. The experi- ment was terminated after 98 days, when the nitrogn-free rams were very emaciated and near death. The average final body weight of the surviving rams was 103, 101 and 63 pounds for the Urea, Drackett and nitrogen-free rations, respectively. There were no statistically signifi- cant differences in volume, motility or total sperm per collection by electrical ejaculation. (T. J. Cunha, A. C. Warnick, P. E. Loggins, J. F. Hentges and R. L. Shirley.) The Effect of Pre-Slaughter Feeding of Sucrose to Swine on Slaugh- ter, Carcass and Quality Characteristics.-The feeding of slaughter hogs over weekends and holidays is costly to the commercial slaughterer; labor and feed costs frequently exceed returns in terms of salable meat and by-products. In practice, hogs are fed only shelled corn, which amounts to a change in diet for some animals and results in decreased feed consumption. The question thus arose of whether or not a more palatable ration would increase consumption to a point detectable by in- creased carcass and liver weights and improved pork quality. A study involving 103 finished market hogs was conducted comparing the pre- slaughter feeding of a ration consisting of 60 percent ground corn and 40 percent sucrose with the feeding of shelled corn. The sugar ration in- creased feed consumption, liver weights, yields of the 4 lean cuts (ham, loin, picnic and butt) and improved tenderness and sweetness of the liv- ers. (A. Z. Palmer.) The Relationship Between Specific Gravity and the Chemical Com- position of the Beef Carcass.-A preliminary study of the moisture, fat, Florida Agricultural Experiment Stations protein and ash components of 41 beef carcasses from yearling standard to top choice steers and heifers is under way. Chilled half carcasses and 9-10-11 rib cuts were weighed in air and then submerged in water and weighed again. Specific gravity was calculated by the formula: weight in air Specific gravity = weight in air weight in water A high relationship was noted between specific gravity of the carcass and the rib and average carcass grade. As carcass grade decreases, specific gravity increases. TABLE 5.-RELATIONSHIP BETWEEN CARCASS GRADE AND SPECIFIC GRAVITY OF THE CARCASS AND RIB. No. of Carcass Grade Sp. Gr. of Carcass Sp. Gr. of Rib Observations 1........ Top Choice 1.0329 1.0353 1 ........ Avg. Choice 1.0490 1.0620 3 ........ Low Choice 1.0392 1.0439 6 ........ Top Good 1.0496 1.0561 5 ........ Avg. Good 1.0632 1.0756 14........ Low Good 1.0616 1.0696 5 ........ Top Standard 1.0652 1.0709 4 ....... Avg. Standard 1.0724 1.0838 2 ........ Low Standard 1.0823 1.0968 Although there was some overlapping due to small differences be- tween each 1/ grade, differences between specific gravities of each aver- age grade were real and distinct for both carcass and rib. The value of the specific gravity of the 9-10-11 rib cut as the value of the specific gravity of its full side will be studied along with chemical composition, degree of marbling, estimated kidney knob percent and amount of out- side fat. (J. W. Carpenter.) The Effect of the Removal of the Preputial Glands of Weanling Boars on Growth, Carcass Fatness and Acceptability of the Carcass Meats.-An attempt was made to surgically remove the preputial glands from six 9- week-old boar pigs. These 6 pigs were then compared in feed lot per- formance, carcass fatness and acceptability of the carcass meat to 6 other intact boar pigs whose glands were not removed and to six bar- rows receiving the same feed treatments and fed to a 240 pound aver- age. Results of the preliminary trial showed that both boars and gland- less boars produced longer, leaner carcasses than barrows. All barrows produced carcasses with no objectionable odor. Two intact boars pro- duced carcasses with only very slight odor, and 1 boar carcass had no detectable odor either in the fat or lean. Four of the boar pigs from which all visible glands were removed at weaning were found to have mature glands at slaughter and produced a characteristic boar odor in the fat. One boar pig died while on trial, and the other pig from which glands were removed had no visible glands at slaughter and produced no boar odor in the fat. (J. W. Carpenter.) The Effect of Temperature on Early Embryonic Survival in Gilts.- Thirty-two Duroc x Landrace gilts were randomly assigned to 1 of 5 treatment groups at 10 days following first estrus and bred to a fertile Annual Report, 1961 boar at second estrus. Gilts were killed 25 days postbreeding, and counts were made of the number of corpora lutea and normal embryos. Group 1 remained on pasture with ample shade; Group 2, constant temperature at 90F; Group 3, one-half of gilts in 2 moved to 60'F 3 days post- breeding; Group 4, constant temperature at 60F; Group 5, one-half of gilts in 4 moved to 90F 3 days postbreeding. There was no difference in conception rate or number of eggs ovulated due to temperature. The average number of normal embryos at 25 days for Groups 1 through 5, respectively, was 12.6, 9.4, 14.1, 12.7 and 11.2 (not statistically signifi- cant). However, all gilts kept at 90oF 3 days after breeding had only 10.4 embryos compared to 13.6 embryos in gilts a 60F 3 days after breeding. High temperatures may be more harmful after 3 days postbreeding than be- fore, which is opposite to the effect in sheep. (A. C. Warnick, H. D. Wallace and A. Z. Palmer.) Use of Flavoring Agents in Pig Starter and Grower Rations.-An ex- periment was conducted to determine if Sucro-Flavor, a synthetic flavor- ing agent, would enhance ration palatability and pig performance. Pigs weaned at 2 weeks of age were given starter rations containing either 20 percent sugar or 0.1 percent Sucro-Flavor. The daily gain, daily feed consumed and feed efficiency was comparable for both groups. (G. E. Combs and H. D. Wallace.) Isocitric Dehydrogenase and Pyruvic Dehydrogenase Activity in the Liver of Rats Fed Diets Varying in Calories and Fat.-The activities of these enzymes were determined in the liver of rats fed 0, 2, 5, 10 and 20 percent fat in the diet. The fat was substituted for sucrose with and without adjustments of calories. Pyruvic dehydrogenase activity was higher in the liver of rats fed no fat than in those fed varying levels of fat. There was no significant difference in the activity of livers of rats fed 2, 5, 10 and 20 percent fat in the diet, either with increasing calories or isocaloric. Isocitric dehydrogenase activity of the liver was correlat- ed with the grams of weight gained per calorie consumed. With an in- crease in the grams of weight gained per calorie consumed, the isocitric dehydrogenase activity increased. (J. F. Easley and R. L. Shirley.) Effect of Protein Intake and Amino Acid Deficiency upon Growth, Growth Recovery and Life Span of Rats.-Laboratory rats have been fed from weaning on purified rations containing 4 different levels of protein in order to determine the effect of protein intake upon growth and lon- gevity. After 1 month on the experimental rations, the weight gains were as follows: 7.5 percent protein, 35 grams; 13 percent, 70 grams; 18 percent, 104 grams; 24 percent, 111 grams. At 7 months the gains were 201, 269, 303 and 305 grams. Gains of the lowest protein group were only 32 percent as much as the highest protein intake at 1 month; however, at 7 months the gain amounted to 66 percent as much as the highest protein intake. No deaths have occurred through 7 months of experimental feeding. Additional rats have been fed from weaning on a semi-purified diet deficient in lysine and tryptophane. Rats consum- ing the deficient diet gained an average of only 13 grams during the first 2 months, while rats consuming a similar ration with lysine and trypto- phane gained 186 grams. Approximately 20 percent of the rats consum- ing the deficient diet died during the first 2 months. A portion of the remaining rats will be continued on the deficient diet in order to de- termine life span. The remaining portion will be changed to the normal diet to study growth recovery following the period of amino acid defi- ciency and retarded growth. (L. R. Arrington.) Florida Agricultural Experiment Stations Effect of Method of Processing on Nutritive Value of Corn for Fatten- ing Steers.-The effect of 4 methods of processing dry shelled corn upon feedlot performance and carcass value were studied in a 112-day exper- iment. Crossbred steers with at least 50 percent Brahman breeding and straightbred Hereford steers were the subjects. The 4 physical forms of corn studied were ground, cracked, flaked (cut, steamed and rolled) and pelleted ground. Flaked and pelleted corn mixtures produced the most efficient gains. Cracked corn produced the least weight gain and was the least efficient. Steers fed ground, flaked and pelleted forms had the same average daily gains 3.2 pounds per day. Carcasses of Hereford steers had higher grades, higher conformation scores, lower carcass ma- turity scores, more marbling in the rib eye muscles and higher cutabil- ity scores than the crossbred steers. Propionic acid production in the rumen at 1 and 8 hour intervals after feeding was highest in steers fed flaked corn; however, neither this nor total volatile fatty acid production in the rumen fully explained the increased feed efficiency observed with the 2 steam-processed corn mixtures. (J. F. Hentges, Jr., A. Z. Palmer and J. W. Carpenter.) Evaluation of Ronphagrass for Pasture in Florida.-Ronphagrass, a perennial bunch type grass, produced less forage than adapted varieties of rye and oats but outyielded wheat during a winter trial at Gaines- ville. Ronphagrass continued to produce fresh green forage in the late spring, when cereal grains matured, but it became dormant during the summer. Ronphagrass tolerated severe frosts which seriously injured the leaves of cereal grains. Ronphagrass contained a high crude protein content (24.5 percent of the dry forage). Ronphagrass was less palatable than cereal grains to beef cattle; however, they would eat it when other forages were not available. Ronphagrass was toxic to sheep. Seventeen days after initial feeding of pure ronphagrass to a sheep, the animal became extremely nervous, as evidenced by trembling, showed abnormal incoordination (Figure 1), and eventually died. There was no recovery in afflicted animals even after they were fed normal diets for 2 months after evidence of toxicity. Exploratory experiments indicated that high nitrogen content in the grass was not the principal cause of the disorder. High levels of avail- able cobalt (approximately 25 times the daily requirement administered orally) prevented the disorder. A high level of oral zinc, intramuscular injections of Vitamin B& or a cobalt bullet in the rumen did not prevent the disorder. Until more trials are conducted, it is not recommended that Ronphagrass be fed to cattle or sheep. (0. C. Ruelke, P. E. Log- gins, J. T. McCall, C. B. Ammerman and C. F. Simpson.) The Physiology and Biochemistry of Hybrid Vigor.-Various straight- bred and crossbred calves are being fed experimentally from approxi- mately 60 days of age to slaughter in order to determine why crossbreds grow faster than straightbreds. Comparative appetite, efficiency of feed utilization and economy of production are being determined. In 2 trials completed, Brahman-Shorthorn crossbred calves have had significantly greater appetite than Brahman and slightly greater intake than Short- horns. There was no significant differences in efficiency of feed utiliza- tion. Shorthorn calves had the lowest rate of growth but stored more body fat and had higher grading carcasses than crossbreds or Brahmans. (M. Koger, T. J. Cunha and A. C. Warnick.) Annual Report, 1961 BOTANY Considerable time was spent during this year in getting the new re- search laboratories in operation. Most of the installation of benches and fixed equipment has been completed. A new controlled environment growth chamber has been placed in operation and will be available for future studies. Dr. H. J. Teas resigned during the year to become director of the Ag-Bioscience Division of the Puerto Rico Nuclear Center in Mayaguez, Puerto Rico. Dr. George J. Fritz joined the department as assistant plant physiolo- gist. He comes from Pennsylvania State University. One project was terminated and 1 project was initiated during the year. PLANT IMPROVEMENT WITH RADIATION Hatch Project 848 H. J. Teas, T. W. Holmsen and Margo Steinman Two problems were investigated. The first involved a study of the effect of gamma radiation on Chrysanthemum Morifolium. The cultivar "Bluechip", and its spontaneous color sports "Bronzechip", "Yellowchip", and "Whitechip" were treated in the cobalt-60 gamma irradiator, receiv- ing doses of gamma radiation ranging between 2,500 and 7,500 roentgens. Observations were taken on growth, morphology, flower color and head type. The final average height of all the irradiated plants was less than that of the controls at the time of flowering. Some common effects of radiation on morphology were inhibition and killing of the terminal shoot, reduction in internode length, fasciations of stems and heads, ex- cessive production of lateral shoots, changes in leaf color and aberrant leaf shapes. "Bluechip" and "Whitechip" were the most prolific in the amount of induced color mutation and the range of colors produced, while "Bronzechip" and "Yellowchip" showed relatively low induced mu- tation rates and a limited range of colors. The second problem was a study of geotropism and transport of in- doleacetic acid (IAA) in normal and ageotropic Zea nays L. The results indicated that IAA exists in at least 3 forms in corn stems: diffusible, exchangeable and actively accumulated. Diffusible IAA was rapidly elut- ed from tissue, whereas exchangeable and actively accumulated IAA were slowly eluted. No evidence of irreversibly bound IAA was observed. No effect of gravity on lateral transport of IAA was observed. It is sug- gested that processes other than lateral transport cause the inequal dis- tribution of diffusible auxin resulting from geotropic stimulation. It was noted that horizontal placement of normal corn stem tissue resulted in a marked reduction in polar transport of IAA, in redistribution of IAA among its various forms and in changes in their rates of elution. Proc- esses involving polar transport may be responsible for the unequal dis- tribution of diffusible auxin resulting from geotropic stimulation. This project was terminated during the year. Florida Agricultural Experiment Stations BIOSYNTHESIS OF CARBOHYDRATES IN PLANTS Hatch Project 953 T. E. Humphreys Absorption of Sugars by Corn Roots.-A study of the absorption of sugars by plant roots was undertaken in an attempt to shed some light on the absorption process per se. Two sugars (glucose and mannose) and a sugar alcohol (mannitol) were used in these studies. The rate of absorption of glucose or mannose increased as the con- centration of the sugar solution bathing the roots was increased and ap- proached a maximum at high sugar concentrations. Conversely, manni- tol absorption increased in direct proportion to the concentration of man- nitol in the bathing solution up to the highest concentration of mannitol used (0.12 molar). At this concentration mannitol was entering the roots at a rate 4 times as great as the maximum rate of glucose absorption and 6 times as great as the maximum rate of mannose absorption. Glucose and mannose were mutually inhibitory. Mannitol did not in- hibit the absorption of the sugars, but was itself inhibited by them. The absorpton of mannitol was not reversible. If roots which had previously absorbed radioactive mannitol were placed in water or in a non-radioactive mannitol solution for 2 hours, no radioactivity was found in the external solution. The absorption of mannitol apparently occurs by a mechanism dif- ferent from that for the absorption of sugars, although from the inhibi- tion studies it seems that some step(s) is common to both mechanisms. METABOLISM OF MOLECULAR OXYGEN BY PLANTS Hatch Project 1042 G. J. Fritz This research project was initiated during the past year. One aspect of the project concerns the study of the direct assimilation of molecular oxygen by plant tissues, that is, the direct addition of molecular oxygen to organic substrate. In order to study direct incorporation of gaseous oxygen by plants, it is necessary to utilize the heavy isotope of oxygen (0'"). Work of this kind requires specialized apparatus and equipment. To date, efforts have been made to complete the fabrication of a vacuum manifold and accessory equipment required for work with 01". The equipment is now assembled and is capable of the following operations: (1) generation of 0"18 from labelled water in an electrolysis cell; (2) analysis of the 018 content of labelled water by equilibration with carbon dioxide; (3) application of s0 to living plant tissue; (4) analysis of the 0"O concentration of the oxygen of organic compounds, by conversion (in vacuo at 500C with appropriate catalysts) of the organic compounds to carbon dioxide. Analysis of the 0"1 content of the carbon dioxide de- rived from tissue samples is performed by mass spectrometry. PRELIMINARY NON-PROJECTED STUDIES Metabolism of Simazine and Atrazine by Sugarcane.-Simazine and Atrazine when applied to the leaves of sugarcane were not translocated to the stalk. Extensive breakdown of these compounds occurred at the site of application, and some of the breakdown products were translo- cated to the stalk. Carbon-14-Atrazine was taken up from the soil or from a water solu- tion by the sugarcane roots, and carbon-14 was rapidly distributed throughout the plant and appeared in the respiratory CO2. After sugar- Annual Report, 1961 89 cane grew for 2 months in soil treated with Atrazine, it was not possible to demonstrate the presence of intact Atrazine in the aerial portion of the plants. (T. E. Humphreys.) Physiology of Dwarfing in Plants.-A biological test was developed for screening the activity of various chemicals that may have dwarfing ac- tivity. This test was standardized against 2-isopropyl-4-dimethylamino-5- methyl phenyl 1-piperidrine carboxylate methyl chloride (Amo-1618), (2- chloroethyl) trimethylammonium chloride (CCC) and tributyl-2, 4-dichlor- obenzylphosphonium chloride (Phosfon). These compounds have all been shown to possess the capacity to dwarf various plants. This study has been conducted with the cooperation of a number of people in the Chem- istry Department who have supplied various quaternary ammonium and phosphonium compounds. 90 Florida Agricultural Experiment Stations DAIRY SCIENCE The Department of Dairy Science encompasses 2 fields of dairy re- search, namely dairy husbandry and dairy products manufacture. The dairy cattle studies are conducted at the Dairy Research Unit at Hague, Florida, and at the West Florida Dairy Unit at Chipley, Florida. The latter unit was assigned to this department July 1, 1960; J. B. White is in charge. A milking herd consisting of about 100 dairy animals is main- tained on about 200 acres of farm land. The Dairy Research Unit at the main station is made up of about 300 dairy animals and is situated on about 1,200 acres of farm land. During the year 50 additional acres have been cleared and put into cultivation, and a new hay barn and implement shelter has been built. A new con- crete horizontal bunker type silo with a 400-ton silage capacity has been built. The dairy products manufacture section has continued to develop its facilities into a modern milk and ice cream plant. Some new equip- ment has been added in the testing laboratories. Dr. K. L. Smith be- came a member of the dairy manufacturing staff in September 1960. ENSILABILITY OF FLORIDA FORAGE CROPS State Project 213 C. J. Wilcox, R. B. Becker and J. M. Wing Evaluation of pearlmillet ensiled in 1959 was completed. Forage con- taining 85 to 90 percent moisture was ensiled with or without various ad- ditives. Consumption rates and intakes of total digestible nutrients and digestible protein by experimental animals varied, but most silages ap- peared to be acceptable. Dry matter recovery from silos with absorbent additives ranged from 90 to 97 percent as opposed to 85 to 89 percent for control silos. Addition of urea (even at low levels) to these forages when ensiling appeared undesirable since it resulted in lower silage consump- tion and increased blood levels of urea and ammonia. Addition of anti- biotics to the silage apparently had little beneficial effect; 2 of 3 antibiotic-treated silages did not compare well with controls. Ten experimental silos were filled in 1960 with oats cut in the early boot stage. Proximate analyses of forage showed it to contain 21.0 per- cent dry matter, of which 9.22 percent was crude protein. Ensiled with various antibiotic and chemical additives, silages varied somewhat in character as follows: range in dry matter content was 14 to 20 percent; dry matter recovery, 75 to 93 percent; crude protein content 7.3 to 9.3 percent; crude protein recovery, 58 to 90 percent. Gross consumption by experimental animals per 1,000 pound body weight ranged from 62 to 75 pounds of silage daily with dry matter intake ranging from 11 to 15 pounds daily. All silages were of acceptable quality; pH ranged from 3.4 to 4.0. There was no evidence of antibiotics in juice or dry matter of any silages to which antibiotics had been added. Digestion trials involving 8 animals each were completed in order to estimate digestibility of organic matter and crude protein; these data are awaiting analysis. (See also Project 356, Animal Science Department.) Annual Report, 1961 FACTORS AFFECTING BREEDING EFFICIENCY, ITS POSSIBLE INHERITANCE, AND DEPRECIATION IN FLORIDA DAIRY HERDS State Project 345 R. B. Becker and C. J. Wilcox Records of breeding and disposal of cows from 5 cooperating Florida dairy herds were accumulated during the year, and a revised life- expectancy table for cows was prepared by joint leader A. H. Spurlock. Records were obtained also of tenure and causes of turnover of bulls during the year in the artificial breeding organizations of Canada and the United States. A new life-expectancy table of the desirable bulls leaving these herds during 1954-1960 showed their average productive ten- ure now to be over 4.1 years. A study of the records accumulated in this project revealed the inci- dence and cause of crampy or progressive posterior paralysis in mature cattle. It is inherited as a recessive character. Episodes become evi- dent in cattle as young as 3 to 4 years old, up to advanced age. The indi- cations are that it may be conditioned by a single gene in heterozygous animals, becoming apparent when the gene is acquired by an animal from both parents. Discomfort from the condition gradually restricts usefulness of the animals. Spastic contractions of muscles of the back and 1 or both rear legs occur under stress, and more frequently as the condition advances. Affected animals restrict their activities. Some deaths occurred from the posteriol paralysis in affected cattle that were retained too long. This investigation is supported in part by a grant from the National Association of Artificial Breeders. (See also State Project 345, Agricul- tural Economics Department.) STUDY OF PRODUCTION, REPRODUCTION AND CONFORMATION OF THE FLORIDA AGRICULTURAL EXPERIMENT STATION DAIRY HERD State Project 575 C. J. Wilcox, R. B. Becker and S. P. Marshall The purebred dairy herd, composed of the 5 major dairy breeds, was maintained at about 300 head during the year. Average milk production per cow was at the highest level in the history of the herd, averaging 10,150 pounds of milk and 466 pounds of fat (2X, 305-day, M.E.). Repro- ductive efficiency declined slightly from the previous year, with fertile cows requiring 2.61 services per conception, primarily due to low concep- tion rates among the Brown Swiss. Close supervision of reproductive performance resulted in an increase of 25 percent in number of cows pronounced pregnant, however, even though the herd did not change ap- preciably in size from the previous year. Frozen semen was used ex- clusively. Horn of pregnancy was established with the following frequen- cies: right, 56 percent; left 44 percent. Four breeds were classified for type with average scores of 79.3 for Holsteins, 80.1 for Guernseys, 82.4 for Jerseys and 85.0 for Brown Swiss. This was the first classification for Brown Swiss. Other scores represented no appreciable change for Holsteins and moderate increases for Guernseys and Jerseys. Most animals served as experimental subjects 1 or more times for other intra- or inter-departmental research projects. Florida Agricultural Experiment Stations SUB-NORMAL MILK: ITS PRODUCTION, CORRECTION AND UTILIZATION Hatch Project 667 R. B. Becker, C. J. Wilcox, J. M. Wing, W. A. Krienke, L. E. Mull and E. L. Fouts The fourth trial was conducted on the relation of feeding practice to composition of milk. Fourteen cows were on experiment, and an equal number served as control animals. The experimental cows received corn silage at the rate of 3 pounds per 100 pounds live weight and mixed con- centrates to balance the offering planned. Seven of the experimental cows received 75 percent of the calculated TDN requirements, while 7 were allowed 85 percent of their TDN needs during the experimental pe- riod. An initial and a post-period with normal feed intakes also were used as bases for comparison. Milk samples were taken from each cow 3 days each week and analysed for fat, solids-not-fat, protein and chlo- rides. Milk yields and body weights declined significantly during the under- feeding. The solids-not-fat percentages increased only slightly with ad- vancing lactation but at a slower rate than in milk of an equal number of control cows. Butterfat percentages were not depressed by the level of underfeeding during the trial. MEDICATED FEEDS FOR DAIRY CALVES Hatch Project 781 J. M. Wing, E. L. Fouts, R. B. Becker and C. J. Wilcox The objectives of this study are to determine the effects of supple- mentary antibacterial and nutritional factors in the feed of young calves. The criteria are general health, growth, efficiency of feed utilization and variations in certain blood components. Eighty-eight calves were ob- served during the period of this report. Replication during the ensuing year will be necessary for definite conclusions, but certain trends seem apparent. Calves supplemented with chlortetracycline alone appear to be superior to comparable controls. Addition of terephthalic acid but not of mycostatin appear to yield further benefits. Hemoglobin levels in untreated control animals appear to decline rapidly during the first 60 days and increase somewhat during the next 30 days. Orotic acid alone or combined with methionine appeared to shorten the depletion period considerably. Guanine and adenine alone or in combination were inef- fective. DIFFERENTIAL ENUMERATION OF LEUCONOSTOC ORGANISMS IN MIXED STRAIN LACTIC CULTURES State Project 919 K. L. Smith The selectivity of media containing 1 of the following dyes was de- termined: brom cresol purple, cresol red, brom thymol blue, crystal vio- let, brilliant green and brom cresol green. None of the dyes would in- hibit all of the strains of streptococcus tested and allow growth of all of the strains of leuconostoc. Tolerance for enzyme inhibitors was tested for the 2 groups of organ- isms. Sodium fluoride, cysteine, alpha-bromopropionic acid and iodoace- tate were tested. Both sodium fluoride and cysteine were inhibitory to the organisms tested, but both groups exhibited approximately the same tolerance to these 2 compounds. Alpha-bromopropionic acid was ef- Annual Report, 1961 fective in separating the organisms. Five strains each of leuconostoc and streptococcus were tested on a tomato juice agar containing alpha- bromopropionic acid. At a molar concentration of the acid of 16 X 10-' all strains of both groups of organisms were inhibited; at 8 X 10-3 molar, only the streptococci were inhibited; at 4 X 10'3 molar medium, all strains grew with no apparent inhibition. Iodoacetate was also effective in separating the 2 groups. At 12.5 X 10' molar concentration, iodoace- tate inhibited all of the organisms, and at 6.3 X 10-" only the streptococci were inhibited. All strains of leuconostoc and some strains of strepto- coccus tolerated 3.1 X 10- molar iodoacetate. The medium and the in- hibitor had to be autoclaved separately and combined aseptically just prior to pouring the plates. THE COST AND NUTRITIONAL VALUE OF GREENCHOP IN FEEDING DAIRY CATTLE State Project 923 J. M. Wing and C. J. Wilcox This study was designed to measure the value of greenchopped feeds in terms of digestible crude protein and total digestible nutrients. During the present year 300 individual digestion trials were conducted. Chemi- cal and mathematical analyses are not complete, but some interesting data are available. The TDN content of most typical forages appears to be somewhat lower than previously published data indicate. Consump- tion rates, however, are much higher; some succulent feeds being con- sumed at rates approaching 200 pounds per 1,000 pounds body weight daily. The digestible crude proteins are much higher than previously thought, and thus the qualitative nature of supplementary feeds may be changed, allowing the use of less expensive mixtures. FACTORS AFFECTING CALF STOMACH COMPARTMENT DEVELOPMENT AND OBSERVATIONS OF SOME CHARACTERISTICS OF THE INGESTA State Project 967 S. P. Marshall and R. B. Becker The influence of type of roughage fed upon stomach compartment de- velopment was studied using male dairy calves. All animals were fed milk through 60 days, supplemental concentrate through 110 days and alfalfa hay through 30 days. During the 31 to 110 day period 1 group was fed corn silage, another received fresh pasture forage and the third group was continued on alfalfa hay. Data to date on 1 Holstein and 3 Jersey calves in each group indicate that type of roughage consumed did not influence significantly the mass of any stomach compartment tis- sue. Average weights of fresh rumen, reticulum, omasum and oboma- sum tissues of calves fed corn silage were 1,384, 183, 387 and 337 grams; for animals receiving fresh pasture forage, 1,437, 197, 314 and 338; and for calves fed alfalfa hay, 1,242, 187, 425 and 398 grams, respectively. Rumen tissue of Holstein calves was significantly heavier (P<0.01) than that of Jerseys. Breed differences for weight of other stomach com- partment tissues were not significant. Average weights of ingesta in the reticulo-rumen cavity, omasum and abomasum of the group fed silage were 13,717, 540 and 1,026 grams; those for the group receiving fresh pasture forage were 9,499, 251 and 660; and for the group fed hay the values were 12,458, 496 and 1,030 grams, respectively. There was less ingesta in the reticulo-rumen cav- ity of calves receiving fresh forage than of those fed hay or silage (P<0.01). The amount of reticulo-rumen ingesta in calves fed silage was Florida Agricultural Experiment Stations larger (P<0.06) than for those receiving hay. There was more of reti- culo-rumen ingesta in Holstein calves than in Jerseys (P<0.01). Differ- ences for amount of ingesta in the omasum or abomasum were not sig- nificant for types of roughage fed or for breed of calves. Rumen papillae development was most advanced in calves fed fresh forage; calves fed corn silage and alfalfa hay showed less papillae de- velopment. Good quality fresh pasture forage or corn silage are satisfactory roughages for calves during the period of 31 through 110 days of age. EFFECTS OF LEVEL AND METHODS OF CONCENTRATE FEEDING ON DAIRY CATTLE State Project 982 J. M. Wing and C. J. Wilcox Most dairy cows in this area are fed bulky concentrates in addition to the usually recommended grain ration. Tnis project concerns the ef- fects of (1) feeding strictly according to theoretical requirements; (2) feeding additional bulky concentrates at the rate of 1 pound per 7 pounds of 4 percent fat corrected milk (FCM), figured individually; and (3) feeding by schedule 2, figured on a group basis. The present year's work was a replication of previous work, which involved 45 cows as- signed for an experimental period of 200 days. Milk yields were adjust- ed for differences in initial production, body weights and days in lacta- tion. Average daily yields of 4 percent fat corrected milk expressed in pounds for the various groups was as follows: (1) 33.2 pounds, (2) 34.3 pounds and (3) 32.8 pounds. These differences cannot be considered as significant statistically. The pasture conditions were extremely good, and it seems doubtful that feeding beyond the usual requirements is desirable when the roughage supply is adequate. GENETIC AND ENVIRONMENTAL INFLUENCES UPON COMPOSITION OF MILK RRF Project 1047 C. J. Wilcox, R. B. Becker, (Regional S-49) W. A. Krienke, J. M. Wing, L. E. Mull and E. L. Fouts Departmental cooperation in this regional research project is entering its second year. Data collected will be utilized on a local as well as a regional level to obtain estimates of genetic and environmental parame- ters associated with milk composition. Samples from all milking cows were tested once monthly for the following milk constituents: fat, solids- not-fat (SNF), protein, chloride and titratable acidity. Milk yields were recorded. Completed 305-day lactation records are contained in Table 6. TABLE 6.-RESULTS OF MONTHLY TESTS OF MILK CONSTITUENTS. J] Actual I I I Titra- Breed Records Milk Fat SNF Pro- Chlo- table I Yield tein ride Acidity (no.) (lb.) % % % | % \ % Ayrshire ... 5 8,570 4.25 9.20 3.11 .129 .153 Brown Swiss 4 9,476 4.24 9.45 3.21 .109 .160 Guernsey .... 26 8,270 4.91 9.42 3.26 .127 .150 Holstein .... 27 12,462 3.69 8.80 2.95 .145 .136 Jersey ........ 66 7,099 5.34 9.58 3.53 .130 .151 Annual Report, 1961 STAPHYLOCOCCUS AUREUS TOXOID IN THE CONTROL OF STAPHYLOCOCCAL MASTITIS Hatch Project 1049 K. L. Smith and C. J. Wilcox The Dairy Research Unit milking herd was tested to determine the incidence of hemolytic staphylococci and the leucocyte count of individ- ual quarter milk samples. Three replicate samples were drawn from each quarter, giving a total of 1,102 samples. Hemolytic staphylococci were present in 33 percent of the samples, but only 5 percent of the samples contained both hemolytic staphylococci and a leucocyte count of 1 million or more. The herd was divided into 2 equal groups, and 1 group was vaccinat- ed with a commercially available toxoid. Six months after vaccinating the herd, the quarter samples testing procedure was repeated. Prelimi- nary statistical analysis of the data showed no significant differences be- tween the treated and control groups with regard to the shedding of hemolytic staphylococci. During the study of the quarter samples, 200 hemolytic staphylococci were isolated and purified. Some of the physiological characteristics of these isolates have been determined (Table 7). TABLE 7.-SOME PHYSIOLOGICAL CHARACTERISTICS OF ISOLATES DETERMINED DURING A STUDY OF SAMPLES OF HEMOLYTIC STAPHYLOCOCCI. Estimated Test Percent Positive Correlation I Coefficient (r)* Coagulase ...................................... 65 - Hemolysis .---.....----..--- ..--------- 86 +I.41 Manitol fermentation .................. 82 +.44 Yellow pigment .................... 59 +.61 Gelatin liquifaction .............. 58 -.54 Estimated for the correlation between coagulase production and the other character- istics listed. DEVELOPMENT AND EVALUATION OF AN INTEGRATED SILAGE AND GRAZING SYSTEM FOR DAIRY CATTLE State Project 1053 S. P. Marshall, J. B. White and E. L. Fouts An annual rotational planting of corn for ensilage followed by sorghum for ensilage and then by oats for grazing is being made to develop and evaluate an integrated silage and grazing system for dairy cattle. Corn planted March 1 has yielded 19 tons of ensilage material per acre. Two 50-ton upright silos have been constructed for ensiling corn and sorghum. Feeding facilities for comparative evaluation of corn and sorghum are being developed. (See also Project 1053, Agronomy Department.) PRELIMINARY NON-PROJECTED STUDIES Effect of Artificial Flavoring Materials in Calf Feeds.-Two groups of 8 young calves including Jersey, Guernsey and Holstein breeds were used in this study. All subjects were raised according to regular herd practices. The only difference in the treatment of the 2 groups was that the concentrate feed for the experimental animals contained a complex mixture of flavoring materials which was formulated just before the ex- Florida Agricultural Experiment Stations periment began. There appeared to be no significant differences in gains in body weight or in the consumption of either hay or concentrate feeds. (J. M. Wing.) Iron Requirements of Dairy Calves.-Six male calves of the Holstein, Jersey and Brown Swiss breeds were confined to wooden pens at birth. They were fed entirely on a milk ration which was high enough in solids to result in constant growth though at a slower than normal rate. Vita- mins and minerals other than iron were supplied at recommended levels. Approximately 7 months were required for depletion of the iron reserves as indicated by hemoglobin levels and hematocrit of the blood. The de- pleted animals will be dosed with different forms of radioactive iron and various tissues and excretion production will be examined for the pres- ence of the supplements. (J. M. Wing.) Effects of Methionine Hydroxy Analogue in a High Urea Ration for Dairy Steers.-Eighteen steers which were approximately 6 months of age were assigned to 2 comparable groups. Jersey, Guernsey and Hol- stein breeds were included. All calves received a simple concentrate feed which was calculated to contain 16 percent of protein equivalent, approximately half of which was derived from urea. Hay and pasture were supplied free choice. Concentrate feeds were supplied in the same amounts to both groups, first at the rate of 6 pounds and later at 8 pounds per head daily. Both groups of animals were healthy. It appears that levels of urea adequate to supply half the protein can be used success- fully with dairy cattle. Addition of methionine hydroxy analogue to this type of ration was not found to be beneficial. (J. M. Wing.) Persistency of Milk Production.-A total of 586 monthly milk produc- tion records of the Holstein herd during 1955-60 were examined to meas- ure the effects of calendar month on persistency. Persistency of indi- vidual cows was expressed for each month as the percentage of milk production for the previous month. Over 80 percent of the freshenings occurred in the months of August through November, and to this extent, effects of month of freshening were removed from the data through ap- propriate statistical techniques. Over-all persistency of first-calf heifers was shown to be 96 percent; of cows, 89 percent; and heifers and cows combined, 92 percent, which agreed well with other investigations. For the combined herd, 9 months fell within 2 percent of the over-all aver- age. July and August were slightly lower at 88 and 86 percent, respect- ively, and November was slightly higher at 97 percent. Recent manage- ment practices apparently have eliminated much of the previously ob- served drop in milk production during the summer months. (C. J. Wilcox.) Losses of Immature Jersey Females.-Herd records for the period 1950-58 were searched to determine the frequency and reason for losses of Jersey females born in the Dairy Research Unit herd. For 334 fe- male births, records showed the following results: stillborn, died at birth or freemartin, 5 percent; died of accident, disease or miscellaneous causes prior to 6 months, 8 percent; died of accident, disease or mis- cellaneous causes from 6 months to freshening, 7 percent; failure to con- ceive, 21 percent; entered milking herd, 58 percent. Previous work has shown that 65 percent of the Jersey females born in the period 1929-49 entered the herd. Comparable losses for this period were 6 percent, 12 percent, 7 percent and 10 percent respectively. The large increase in recent years of animals which failed to conceive (21 percent as opposed to 10 percent) was attributable to an outbreak of vibriosis in the early 1950's. (C. J. Wilcox.) Annual Report, 1961 Chloride Content Important in Fortified Skimmilk.-Two lots of milk, 1 selected from cows known to produce milk of low chloride content and the other of high chloride content, were used in the study. Some of the skimmilk of each lot was concentrated in a stainless steel vacuum pan, and this was used to fortify its respective skimmilk by 2.0 percent solids. Composition for the 2 lots of skimmilk and their respective for- tified products were: low chloride-solids, 9.98 and 11.98 percent; protein, 3.45 and 4.17 percent; chloride, 0.132 and 0.15 percent; high chloride-solids 9.04, and 11.04 percent; protein, 3.12 and 3.81 percent; chloride, 0.18 and 0.22 percent. Five experienced dairy products judges sampled the 2 skimmilks and the respective fortified skimmilks. Two of the 5 criticized the high chlo- ride skimmilk and the high chloride fortified skim as salty, with the lat- ter considered objectionable. It has been established that the salt taste threshold of people varies. High chloride content of fortified skimmilk may result in consumer com- plaints or in discontinuance of use of the product. (W. A. Krienke.) Testing Cottage Cheese Curd for Solids.-Cottage cheese curd was dis- persed with alkaline solutions of different concentrations and in different amounts. After comparison of results the following procedure was con- sidered satisfactory. Weigh 25 g. of curd into a 250 ml. Erlenmeyer flask, add 25 ml. of alkali solution (1.2 ml. 50 percent NaOH solution made to 100 ml.); stopper the flask and place on mechanical shaker un- til all particles are dispersed (2 to 3 hours); use 2 g. for the Mojonnier solids test. Percent solids of curd = (percent solids of sample -0.30) X 2 The dry material in the aluminum dishes is easily removed after the addition of distilled water, heating to boiling and cooling for a few min- utes. More than the recommended amount of alkali did not shorten disper- sion time appreciably; it caused etching of the aluminum dishes as evi- denced by appearance and weight losses. (W. A. Krienke.) Formol Titration Test Used In Evaluating Cottage Cheese Cultures. -Observations that slow acid production during cottage cheese setting sometimes resulted in a "weak set" and a soft pasty-type curd suggested possible proteolysis of casein. In comparisons using a "slow culture" versus a "fast culture" the formol titration test was used on filtered whey taken immediately after cutting of the curd and again mid-way in the cooking period. For skimmilk (9.45 percent solids) and for recon- stituted low-heat non-fat dry milk (10.5 percent solids) the respective for- mol titration values at both times were, for the "slow culture," 2.6 and 2.5; for the "fast culture," 1.4 and 1.5 (ml. 0.1 N alkali per 18 g. whey). The results suggest a protein breakdown (perhaps casein proteolysis) or an interference of some type that prevented complete and/or adequate coagulation of casein. Visual inspection of the filtered whey samples re- vealed a slight cloudiness in appearance of the "slow culture" whey. This finding suggested possible use of the formol titration test as a useful tool for evaluating the quality of cultures intended for cottage cheese manufacture. Additional research is planned to investigate cer- tain aspects that may be related to this condition. (W. A. Krienke.) Protein Content of Milk More Reliable than Solids Content in Pre- dicting Yield of Cottage Cheese.-High protein producers (primarily Guernseys) versus low protein producers (primarily Holsteins) were se- lected for pooled samples of milk to study the relationship of protein content of skimmilk to yield of cottage cheese. After pasteurization at Florida Agricultural Experiment Stations 143'F for 30 minutes a portion of each lot of skimmilk was concentrated in a vacuum pan. Triplicate trials were made involving 18 vats of cottage cheese. For each trial, adjustments in composition were made so that each of the pooled batches resembled its companion with respect to protein content in 1 set of comparisons and solids content in another set. Yields of curd were adjusted to an 80 percent moisture basis. The high protein skimmilk (average 3.83 percent protein) yielded 24.9 percent more cottage cheese curd than did the low protein skimmilk (average 3.12 percent protein). For the 6 comparisons based on protein content, regardless if increased from the low to the high or decreased from the high to the low, on the average, a difference of only 1.2 percent in yield of cottage cheese curd was obtained. For the 6 comparisons based on solids content (compared similarly to protein basis), on the average, a difference of 12.5 percent in yield of cottage cheese curd re- sulted. These data demonstrate the advisability of changing from a solids basis to a protein basis in skimmilk composition for predicting yields of cottage cheese. The results also are evidence that if these skimmilks had been manufactured into non-fat dry milk and reconstituted to a solids content of 10.0 percent, yield of cottage cheese curd for the high protein product could have been expected to exceed that of the low protein product by an average of 10.6 percent. (W. A. Krienke and L. E. Mull.) Milk Composition.-Data from 2,052 randomly selected, daily, compos- ite milk samples from Holsteins, Jerseys and Guernseys of the Dairy Re- search Unit herd were analyzed. Within-breed zero-order correlation were obtained between all combination of variables: (1) percent solids not-fat (SNF), (2) percent fat, (3) pH, (4) percent acidity, (5) percent protein, (6) percent chloride and (7) milk yield from which sample was taken. Within-breed multiple correlations (R2) between (1) and (2) to (7) ranged from 0.76 to 0.86; R' over all breeds was 0.89. R2 over all breeds was essentially unaffected by deletion of variables (3), (4) or (7) alone or in combination. Ranges of partial correlations (within- breeds) between percent SNF and other variables were, with (2) 0.18 to 0.35, (3) -0.09 to -0.14, (4) 0.06 to -0.13, (5) 0.56 to 0.69, (6) -0.37 to -0.61 and (7) -0.06 to -0.15. Within-breed or combined breed regres- sion equations which attempted to predict percent SNF from all other measurements were associated with unbiased standard errors of estimate of 0.20 to 0.23. Variability in percent SNF was practically unrelated to percent acidity, pH and the milk yield from which the sample was taken, but was moderately related to percent fat, percent protein and percent chloride. (W. A. Krienke and C. J. Wilcox.) Heat Treatments Affect Yield and Quality of Cottage Cheese.-The skimmilks for this study involving 30 vats of cottage cheese were sep- arated from mixed herd milk. After pasteurization (control samples 162'F for 17.4 seconds and test samples 143, 150, 155, 160 and 165F for 30 minutes) portions were concentrated from about 9.5 percent solids in a vacuum pan to 15 to 17 percent solids. The latter portions were used to standardize portions of respective skimmilks so that final solids con- tents for comparative studies were 9.5, 10.0 and 10.5 percent solids. The cottage cheese curd was made by the short-set method, and final yields were calculated to an 80 percent moisture basis. While data on yields of curd for the different test samples varied somewhat irregularly from the controls, the yields at the 160 and 165F treatments were substantially higher than the others. This indicates some precipitation of B-Lactoglobulin trapped in the coagulated casein. Annual Report, 1961 99 However, at these temperatures and at 155F the characteristics of the curd ranged from weak and fragile to very pasty with the increases in temperature. Curd of excellent quality at each of the 3 levels of solids resulted from the control samples and the test samples pasteurized at 143 and 150F 30 minutes. These results suggest that for cottage cheese purposes, heat treat- ments must not exceed 150F for 30 minutes or its equivalent, whether the milk product used be skimmilk, condensed skimmilk, or non-fat dry milk. (L. E. Mull and W. A. Krienke.) |