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HISTORIC NOTE
The publications in this collection do
not reflect current scientific knowledge
or recommendations. These texts
represent the historic publishing
record of the Institute for Food and
Agricultural Sciences and should be
used only to trace the historic work of
the Institute and its staff. Current IFAS
research may be found on the
Electronic Data Information Source
(EDIS)
site maintained by the Florida
Cooperative Extension Service.
Copyright 2005, Board of Trustees, University
of Florida
Bulletin 5
COOPERATIVE DEMONSTRATION WORK
In
AGRICULTURE AND HOME ECONOMICS
UNIVERSITY OF FLORIDA DIVISION OF AGRICULTURAL
EXTENSION AND UNITED STATES DEPARTMENT
OF AGRICULTURE COOPERATING
P. H. ROLFS, Director
SUBIRRIGATION
A. P. SPENCER, District Agent
C. M. BERRY, Agent Seminole County
Fig. 1.-Water Supply Flowing into Water Main
Bulletins will be sent free on application to the Extension Division, Gainesville, Fla.
July 1916
MAPOF iP O L '
FLORIDA ...42
SHOWING AREAS OF s
ANATEE
ARTESIAN FLOW E OT
SANTA --- DEJACKSON
r ?0 OKALOOSA WA LTAON SUNGT O
-JP
-~O
d
Fig. 2.
Subirrigation
The purpose of subirrigation is to control the moisture in
the soil so that plants will have at all times sufficient water con-
veyed to their roots by capillary attraction without wetting the
blanket of surface soil of the field. The advantages of this
method are: The water supply is constant and regular. The
plants receive no excess water to encourage fungus and other
diseases. No crust forms on the surface of the soil. The soluble
fertilizers are not washed deep into the soil beyond the reach of
the roots as they are when heavy rains occur or when quantities
of water are applied to the surface.
The control of the moisture in the soil is absolute if this
system of subirrigation is properly installed and the conditions
are suitable for such a system.
ESSENTIALS FOR SUCCESSFUL OPERATION
1. An abundance of water is necessary. This is usually
supplied by artesian wells obtained by driving iron pipes down
into the artesian stratum, and allowing the water to rise in the
pipe to a height somewhat above the surface of the ground.
The water can also be brought to the surface with force pumps
where it rises to within easy reach from the surface.
2. A subsoil or floor, composed of clay, marl, or hardpan,
located at a depth of three to five feet below the surface to hold
the water and prevent its escape downward.
3. A foot or more of coarse sand on top of the subsoil or
bottom of the irrigated depth that will readily absorb and dis-
tribute evenly the water to be used in grading the artificial water
table.
4. A top soil of sandy loam that is neither too porous nor too
compact, and which will convey the water freely by capillary
attraction.
5. Land that admits perfect drainage. It should have a fall
of about one inch to one hundred feet.
6. Land that is level, without depressions or raised places.
Wherever the foregoing conditions obtain and wherever the
crops to be grown justify it, this system of subirrigation should
give satisfactory results, but with any one of these essentials
lacking it is not likely to give satisfaction. The system also
supplies drainage and aeration.
Cooperative Extension Work
Subirrigation is used more extensively
in the Sanford and
Oviedo districts,
along the south-
ern border of
Lake Apopka
and in sections of
Manatee County,
than in other
parts of Florida.
The water is sup-
plied by artesian
wells from 125 to
1000 feet deep.
These wells are
secured at vary-
ing depths of from
150 to 1500 feet at
different places
thruout Florida as
shown in Fig. 2.
A full description
of the artesian wa-
ter supply may be
secured from Flor-
ida State Geologi-
cal Survey, Tal-
lahassee, Fla.
MATERIALS
S AND CON-
., STRUCTION
The follow-
Fig. 3.-Water Main ing list gives the
materials necessary to construct a subirrigation system for a unit
of 21 acres. The lines of lateral tile are 24 feet apart.
28 pieces of Terra Cotta Pipe 12x30 inches
158 4x24
4620 drainage tile 3x12 "
14 iron nipples 2x6 "
14 3x6
9 sacks of cement
14 2-inch wooden plugs
14 3-inch
2 4-inch "
Cost of artesian wells vary in different localities from 40c to $1 a foot.
The cost of labor for laying the system varies from $50 to $75 per acre.
Bulletin 5
The terra cotta or ce-
ment sewer pipes 12 inches
in diameter and 30 inches
long are placed upright
twenty to twenty-four feet
apart. The bottom ends
are plugged with cement.
These upright pipes are
known as the supply pock-
ets. (Fig. 4.) They are con-
nected by four-inch terra
cotta water pipes, cement-
ed tight at all joints. This
constitutes the water main.
(Fig. 3.) From each supply
pocket is laid at right an-
gles to the water main a
lateral line of tile. These
lines are made of ordinary Fig. 4.-Supply Pocket
three-inch tiles, placed end
to end and not cemented. Each joint is covered with a handful
of sawdust or palmetto fibre or some other available material to
prevent sand passing thru the joints and clogging the tile.
At the end of each lateral,
Opposite the main, a stop
pocket is placed. (Fig. 5.) The
tile is connected with it in the
same manner as to the supply
pocket.
Another hole is cut direct-
ly opposite in the stop pocket
and three tiles are laid to con-
nect it with an open drainage
ditch. A three-inch iron nip-
ple six inches long is used to
i 4 connect the outlet tiles with
Sthe stop pockets. The stop
pockets provide a means for
holding the water in the tiles
when it is necessary.
LAYING THE WATER MAIN
The level of the land
Fig. 5.-Stop Pocket
Cooperative Extension Work
should be accurately determined by a competent surveyor. The
water supply or well (Fig. 1) is located at the highest corer of
the field to be irrigated. The water main is laid from the well
along the highest side of the field at a depth of sixteen to twenty-
four inches and is allowed the natural fall of the land. The
supply pockets are placed twenty to twenty-four feet apart in the
main. All joints and connections are made water tight with
concrete consisting of three parts of sharp sand to one of cement.
LAYING THE LATERALS
The tiles of the laterals are laid from the supply pockets
which are always located on the high side of the field along the
main. The union between the first tile and the supply pocket is
made with a nipple of two-inch iron pipe six inches long. (Fig. 6.)
Fig. 6.-Nipple Fitted Into Tile
One end of this nipple is fitted snugly into the end of the tile and
the other end is slipped into the supply pocket and both are
cemented water tight. The tiles fit together as closely as possible.
The joints are covered with sawdust or palmetto fibre to keep
out sand.
To OBTAIN THE PROPER GRADE
Care must be taken to have the tiles properly placed. The
ditches in which the irrigation tiles are to be laid are dug one
foot wide and eighteen inches deep and should have a fall of one
inch to one hundred feet. The bottom of the ditch is made as
even as possible and then smoothed with a tiling scoop to give a
good bed for the tile. If water is allowed to flow slowly down the
ditch any elevations or depressions along the bottom can be detect-
ed. A tiling scoop can be used to level the bottom until the water
runs slowly and regularly from one end of the ditch to the other.
SAFETY APPLIANCES
Sometimes it is advisable to place a partition or gate in the
stop pocket to provide a safety appliance against overflow. This
Bulletin 5 7
is made by fitting into the stop pocket a vertical cement partition,
having two holes the size of the opening in the nipple. One of
these holes is placed on a level with the nipple and the other
Fig. 7.-Plan of Subirrigation System
A.-Supply Pockets B.-Stop Pockets C.-Water Main
Fig. 7.-Plan of Subirrigation System
A.FSupply Pockets 7 .-Stop Pockets C.-Water Main
Cooperative Extension Work
nearer the surface. This appliance should always be installed
when it is desired to hold the water in the tiles. Otherwise, there
is a constant danger of raising the water table too high and flood-
ing the land. By placing the plug in the bottom hole of this
partition the water will rise as high as the upper hole and then
flow over and escape into the open ditch.
TURNING IN THE WATER
When ready to set the land with young plants, such as lettuce
or celery, the outlet holes of the stop pockets are plugged. The
water is then turned into the tiles, and is allowed to rise until the
surface of the soil is evenly moistened, but not puddled. The
plants are then set in the moist soil, after which the water supply
is cut off. The plugs in the stop pockets are removed and the
surplus water is allowed to drain away into the ditches. This
admits a circulation of air thru the tiles, which readily permeates
the soil.
After this, the water is not again brought to the surface of
the soil during the life of the crop. As soon as moisture is
needed, the water is turned into the tiles and allowed to run con-
stantly unless the soil becomes too moist or periods of rain occur.
The water table, which furnishes the plants with moisture by
capillary attraction, is held about 18 inches below the surface.
The amount of water needed to hold the table at this height is
usually controlled by regulating the flow into the main line. Its
height is determined by the height to which the water rises in
the supply pockets. The depth at which the water table is to be
maintained depends on the nature of the crop. For example,
celery and lettuce require more water than tomatoes.
SIZE OF WELLS
Where flowing wells can be had, a two-inch well is the most
desirable size. If increased water supply is needed better results
will be obtained from a number of such wells than from one or
more larger wells. One two-inch well for every two and a half
acres of land is advised for vegetable growing or wherever a lib-
eral supply may be needed quickly. The well is driven and cased
with ordinary iron pipes. Galvanized pipes should be used for the
top joint or, the pipe above ground should be painted to protect it
from rust.
Bulletin 5 9
DISTRIBUTING THE WATER TO A LARGER AREA
When only a small flow of water in each lateral is needed,
because of the kind of crop, recent rains, or a sufficient moisture
already existant, the area that may be watered from one well
may be increased by placing plugs having one-half-inch holes
bored thru them, in the nipples connecting the laterals with the
supply pockets. These reduce the flow into each lateral- and
enable the well to furnish water to three or four times the usual
Fig. 8.-Inserting Plug in Supply Pocket
area. If, however, the soil is dry and liberal watering needed,
the full two-inch opening of the nipple should be used.
In case the water supply is insufficient the field can be
watered in sections, by placing a large plug in the main line at
any desired supply pocket (Fig. 8) until the soil is sufficiently
moistened; then plug the nipples leading into the laterals of the
watered area and allow the water to pass down the main into the
next area to be irrigated. The laterals should always be open at
the outlets to give a circulation of water thru the pipes and soil.
Where it becomes advisable to reduce the amount of water
because of a limited supply, or of heavy expense in obtaining it,
a saving may be made by placing plugs with three-fourths-inch
holes in the nipples of the stop pockets, thereby reducing the
amount of water flowing out of the laterals. This causes the
water to circulate less rapidly and increases the proportions ab-
sorbed by the soil particles. In such cases, however, safety
Cooperative Extension Work
appliances should always be provided in the stop pockets as
there is danger of flooding the surface if the small openings be-
come clogged.
SUBIRRIGATION AS DRAINAGE
A subirrigation system, properly installed, provides a perfect
subdrainage system during excessive rains, or whenever the soil
becomes too wet. It prevents water-logging, which is so de-
structive to bacterial life in soil. In a few hours after the heav-
iest rains it is possible to turn the land with heavy plows.
CROPS THAT MAY BE IRRIGATED
Subirrigation can be used for most truck and field crops
grown in Florida. It may be used in groves where the surface
and subsoil are suited, but roots of the trees may plug the
tile. In this case it will be necessary to re-lay the tiles every
four or five years.
Tomatoes, watermelons, cantaloupes and sweet potatoes are
not usually benefited by subirrigation. They prefer a drier soil
except during periods of continued drought. Celery, lettuce and
Irish potatoes require an abundance of water and are grown most
successfully in Florida where subirrigation is practiced.
EXCESSIVE IRRIGATION
Where the water supply is abundant it is easily possible to
give the crop too much water. Injuries from excessive irriga-
tion are usually more serious and much harder to overcome than
those from lack of water. Plants start slowly or become stunted.
Many will actually die or become worthless, or they may not
mature early enough to obtain a good market.
The bad results produced by excessive irrigation- are due to
driving the air out of the soil, filling the spaces with water, and
thus creating unfavorable conditions for soil bacteria. It causes
heavy loss of fertilizer by leaching, especially the ammonia,
which is very soluble and expensive. Crops grown on lands that
are irrigated too heavily are usually sappy, perishable, and lack-
ing in good flavor. The soil is made compact and more difficult
to cultivate. Over-irrigated soil is likely to become sour, which
is detrimental to most crops.
Cooperative Extension Work
appliances should always be provided in the stop pockets as
there is danger of flooding the surface if the small openings be-
come clogged.
SUBIRRIGATION AS DRAINAGE
A subirrigation system, properly installed, provides a perfect
subdrainage system during excessive rains, or whenever the soil
becomes too wet. It prevents water-logging, which is so de-
structive to bacterial life in soil. In a few hours after the heav-
iest rains it is possible to turn the land with heavy plows.
CROPS THAT MAY BE IRRIGATED
Subirrigation can be used for most truck and field crops
grown in Florida. It may be used in groves where the surface
and subsoil are suited, but roots of the trees may plug the
tile. In this case it will be necessary to re-lay the tiles every
four or five years.
Tomatoes, watermelons, cantaloupes and sweet potatoes are
not usually benefited by subirrigation. They prefer a drier soil
except during periods of continued drought. Celery, lettuce and
Irish potatoes require an abundance of water and are grown most
successfully in Florida where subirrigation is practiced.
EXCESSIVE IRRIGATION
Where the water supply is abundant it is easily possible to
give the crop too much water. Injuries from excessive irriga-
tion are usually more serious and much harder to overcome than
those from lack of water. Plants start slowly or become stunted.
Many will actually die or become worthless, or they may not
mature early enough to obtain a good market.
The bad results produced by excessive irrigation- are due to
driving the air out of the soil, filling the spaces with water, and
thus creating unfavorable conditions for soil bacteria. It causes
heavy loss of fertilizer by leaching, especially the ammonia,
which is very soluble and expensive. Crops grown on lands that
are irrigated too heavily are usually sappy, perishable, and lack-
ing in good flavor. The soil is made compact and more difficult
to cultivate. Over-irrigated soil is likely to become sour, which
is detrimental to most crops.
Cooperative Extension Work
appliances should always be provided in the stop pockets as
there is danger of flooding the surface if the small openings be-
come clogged.
SUBIRRIGATION AS DRAINAGE
A subirrigation system, properly installed, provides a perfect
subdrainage system during excessive rains, or whenever the soil
becomes too wet. It prevents water-logging, which is so de-
structive to bacterial life in soil. In a few hours after the heav-
iest rains it is possible to turn the land with heavy plows.
CROPS THAT MAY BE IRRIGATED
Subirrigation can be used for most truck and field crops
grown in Florida. It may be used in groves where the surface
and subsoil are suited, but roots of the trees may plug the
tile. In this case it will be necessary to re-lay the tiles every
four or five years.
Tomatoes, watermelons, cantaloupes and sweet potatoes are
not usually benefited by subirrigation. They prefer a drier soil
except during periods of continued drought. Celery, lettuce and
Irish potatoes require an abundance of water and are grown most
successfully in Florida where subirrigation is practiced.
EXCESSIVE IRRIGATION
Where the water supply is abundant it is easily possible to
give the crop too much water. Injuries from excessive irriga-
tion are usually more serious and much harder to overcome than
those from lack of water. Plants start slowly or become stunted.
Many will actually die or become worthless, or they may not
mature early enough to obtain a good market.
The bad results produced by excessive irrigation- are due to
driving the air out of the soil, filling the spaces with water, and
thus creating unfavorable conditions for soil bacteria. It causes
heavy loss of fertilizer by leaching, especially the ammonia,
which is very soluble and expensive. Crops grown on lands that
are irrigated too heavily are usually sappy, perishable, and lack-
ing in good flavor. The soil is made compact and more difficult
to cultivate. Over-irrigated soil is likely to become sour, which
is detrimental to most crops.
Bulletin 5
EXTENSION WORK IN AGRICULTURE AND HOME
ECONOMICS IN THE STATE OF FLORIDA
The demonstration work in agriculture and home economics
in Florida is conducted cooperatively between the Extension
Division of the University of Florida and the States Relations Ser-
vice of the United States Department of Agriculture, and is pri-
marily educational.
The principal work is conducted under three projects:
County Cooperative Demonstration Work with Adult Farmers;
Boys' Agricultural Clubs;
Home Demonstration Work.
County Demonstration Work is conducted by demonstra-
tion agents who give instruction in better methods of agriculture,
horticulture, live stock, and dairying. The instruction is given
largely thru such demonstrations on farms in the county as will
give object lessons to others in the same community. The county
agent becomes the leader in various forms of extension activity
and extends his work in every agricultural section of the county.
Boys' Agricultural Clubs are devoted to corn and pig clubs.
The corn clubs have been organized generally thruout the State
and have awakened new interest for staple crops, opening the way
for a more stable agriculture. The larger yields of corn produced
have added materially to the value of the corn crop in Florida.
The greatest benefit, however, has come by placing emphasis
on the economic importance of growing staple crops necessary for
home consumption and maintenance of the necessary livestock.
The boys' pig clubs represent a progressive movement to en-
courage profitable hog raising. Pig club boys begin with pure-
bred brood sows. They are taught to give the pig the proper care,
grow the best feeds for its upkeep, and keep accurate records of
all costs and gains, and thereby work out the most profitable sys-
tems of hog raising in Florida.
The Home Demonstration Work is carried on cooperatively
with the Florida State College for Women. It is organized pri-
marily for the benefit of the women and girls in rural commun-
ities. Agents are employed for various counties to instruct in
home economics and domestic art, which is accomplished among
the girls by organizing them into canning and other clubs, fol-
lowed by demonstrations and lectures in home economics in the
rural school centers and rural homes. The work is carried on in
cooperation with the county boards of education. The women's
clubs are organized in various localities. The object of these
clubs is to study home economics problems.
The poultry club work is carried on among the various
women's and girls' clubs with a view of studying home poultry
raising and the marketing of poultry products.
Cooperative Extension Work
BOARD OF CONTROL
P. K. YONGE, Chairman, Pensacola, Fla.
T. B. KING, Arcadia, Fla.
E. L. WARTMANN, Citra, Fla.
W. D. FINLAYSON, Old Town, Fla.
F. E. JENNINGS, Jacksonville, Fla.
J. G. KELLUM, Secretary, Tallahassee, Fla.
COOPERATIVE DEMONSTRATION WORK IN AGRICUL-
TURE AND HOME ECONOMICS
STAFF
A. A. MURPHREE, President of the University.
P. H. ROLFS, Director.
C. K. MCQUARRIE, State Agent.
A. P. SPENCER, District Agent for East and South Florida.
E. S. PACE, District Agent for North and West Florida.
G. L. HERRINGTON, Boys' Club Agent.
AGNES ELLEN HARRIS, State Agent for Home Demonstration
Work.
SARAH W. PARTRIDGE, District Agent for East and South Florida
Home Demonstration Work.
HARRIETTE B. LAYTON, District Agent for North and West
Florida Home Demonstration Work.
MINNIE FLOYD, Agent for Poultry Clubs.
A. H. LOGAN, Hog Cholera Demonstration Work, Bureau of An-
imal Industry, United States Department of Agriculture.
M. N. BEELER, Editor.
BESSIE V. GLOVER, Secretary.
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