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Everglades Station Mimeo Report EES 67-3 September 1966
SUGARCANE HERBICIDES FOR THE FLORIDA EVERGLADES1-
2/
J. R. Orsenigo-
Recommendations and suggestions given here are based primarily
on research conducted by the Everglades Experiment Station but
may be supplemented by data developed elsewhere. Growers are
urged to observe the manufacturer's label and precautions for
commercial use of herbicides in sugarcane.
Herbicides are effective, economical tools in sugarcane production but are
not substitutes for good agronomic practice. The best chemical performance is
obtained by adhering to certain guides: USE the RIGHT CHEMICAL for the particular
weed problem at the RIGHT TIME, in the RIGHT AMOUNT, WAY AND PLACE.
The economics and potential of weed control chemicals in farm management
must be evaluated by each grower for his particular situation. Initial use of
these chemicals should be restricted to a limited acreage for familiarization.
Many preemergence herbicides are effective only against germinating weed
seed and small annual weed seedlings. These chemicals generally do not control
emerged weeds and should be applied promptly after planting or to freshly weeded
soil. Preemergence chemicals perform best when applied to a moist soil surface
or when application is followed by moderate rainfall.
Broadcast-overall herbicide application is ifcated in plaht sugarcane
since the conventional ridge-and-furrow planting/system does ,9t rmit ready
tillage of row middles when chemicals are appli to the dr~t. ss pronounced
ridge-and-furrow to almost flat planting are de liable ifJpreemerg nce herbicides
are to be used. /
Herbicide rates in this mimeo report are stated on a PER-TED ACRE basis
in terms of the usual commercial formulation. Thorough_~un ground or weed
coverage is necessary. Sprayable (soluble salts, emulsifiable concentrates and
wettable powders) and granular formulations (some chemicals) are available. The
customary active ingredient content of herbicides mentioned in this report is
given in the Glossary along with herbicide nomenclature and terminology.
RECOMMENDED herbicidal treatments (chemical, rate, manner of use) are those
generally reliable for commercial production when used as specified. Growers
without prior herbicide experience should confine initial applications to a
limited acreage.
SUGGESTED herbicidal treatments represent promising materials not fully
evaluated locally or materials approved for sugarcane not generally applicable
to the Everglades. Growers may wish to use these on a very limited acreage.
/ A revision of EES 65-25 and earlier Mimeo Reports.
SAssociate Horticulturist, University of Florida, Everglades Experiment Station,
Belle Glade, Florida.
CHEMICAL WEED CONTROL FOR SUGARCANE
PREEMERGENCE TO ANNUAL WEEDS IN PLANT CANE
A. Early-fall planting (mid-August to mid-October): Use modified ridge-and-
furrow or flat planting and apply herbicides immediately after covering and
bedding when mature seed of good quality is planted at the proper rate. Use
procedure "B" if seed cane quality is poor or planting rate is low.
B. Late-fall planting (after mid-October): Cultivate until need for replanting
"skips" can be determined. After replanting "skips" in stand or after a
decision not to replant! clean-cultivate to a modified ridge-and-furrow and
apply herbicides immediately with a semi-directed spray to minimize wetting
the cane foliage. Granular formulations may be applied over the plants.
RECOMMENDED PREEMERGENCE
"Randox"
"Randox"
plus
2,4-D amine
"Limit"
"Randox"
plus
"Atrazine"
"Fenac"
10 qts/A
8 to 10 qts/A
+
2 qts/A
8 qts/A
Note
6 qts/A
4 to 5 lb/A
6 gpa
FOR ORGANIC SOILS
Usually requires a postemergence broadleaf
weed control treatment at 1 to 2 months after
application.
This combination will provide good grass and
broadleaf weed control for several months under
average soil moisture and rainfall conditions.
A commercial formulation of "Randox" and 2,4-D
acid.
"Randox" and "Limit" are not postemergence
herbicides and will not control perennial or
established weeds. Grass weed control is
improved with good soil moisture or light rain-
fall and is decreased by heavy, persistent
rainfall.
Duration of good annual grass and broadleaf
weed control is 2 to 4 months after fall or
spring application. The combination also has
postemergence activity against small grass and
broadleaf weeds. Cane foliage contracted by
the combination will be "burned" but future
growth is unaffected.
Provides good annual grass weed control which
has continued into the ratoon crop following
application. Usually requires a postemergence
broadleaf weed control treatment 1 to 2 months
after application and in the following crop.
'UGGESTED PREEMERGENCE
"Atrazine"
"Karmex:;
or
"Telvar"
4 to 5 lb'o/
2 to 4 lb/A
Good soil moisture or light rainfall is essential.
Broadleaf weed control may be superior to annual
grass weed control. May be used,as a split appli-
cation: 2-1/2 lb/A preemergence and 2-1/2 lb/A
later as required. Application may be delayed
until small weeds and cane have emerged.
Control of broadleaf weeds better than grasses,
especially under low soil moisture. An additional
directed postemergence spray of 2 lb/A may be
applied to prolong weed control.
PREEMERGENCE TO_ANNUAL W EEDS IN RATOON CANE: ALL SOILS
C. Before or after emergence of stubble growth in trash-free rows only:
SUGGESTED PREEMERGENCE
After fertilization, tillivate row middles, then apply chemicals listed for
plant crops above. Apply soon after ratooning in early fall and late spring
harvest; do not delay more than 2 weeks during remainder of season. Tillivate
and apply herbicides to trash rows when trash has decomposed. Tillage machinery
should not throw weedy soil onto chemically treated areas.
POSTEMRGENCE TO SUGARCANE AND ANNUAL WEEDS: ALL SOILS: PLANT OR RATOON CROPS
D. For emerged annual grasses only: Ale;andergrass, crabgrass, goosegrass; etc.
RECOMMENDED POSTEMERGENCE
"Dowpon"
"Atrazine"
4 lb/A
4 Ib/A
"Atrazine" 1 lb/A
- 2,4-D amine 1/2 lb/A
SSurfactant 1/24 by vol.
Apply as directed or semi-directed sprays to avoid
wetting cane foliage. Apply 2 or 3 times at 7 to
14 day intervals. Bermudagrass and other perennial
grasses will be controlled also. Serious yield
reduction can occur if much sugarcane foliage is
wet repeatedly. Grass weeds die slowly following
treatment.
Apply only to seedling grass (and broadleaf) weeds
2 to 3 inches tall and with not more than 3
expanded leaves. Semi-directional equipment
preferred With good soil moisture or light rainfall
this treatment will provide some residual control
of annual grass and broadleaf weeds, especially on
sandy soils.
Apply tank-mix combination as semi-directed spray
to annual grass and broadleaf weed seedlings not
more than 3 inches tall. 2,4-D may be omitted in
fields near sensitive crops. May be repeated 2 or
3 times as required by weed growth. Effectiveness
diminishes in April and when applied to tillering
grasses.
FOR SANDY SOILS
SUGGESTED POSTEMERGENCE
"Fenac"
+ 2,4-D
5 to 6 qts/A
1 to 1-1/2 lb/A
"Karmex" 1
+ 2,4-D amine 1/2
r- I facbant 1/4 to
by
lb/A
Ib/A
1/2%
vol.
Apply tank-mix combination as semi-directed spray
to annual grass and broadleaf weed seedlings not
more than 3 inches tall. May be repeated within
2 or more weeks as required by Weed growth. Annual
grass seedlings not killed will have restricted
root growth.
Apply tank-mix combination ONLY as directed spray
to annual grass and broadleaf weed seedlings not
more than 3 inches tall. 2,4-D may be omitted in
fields near sensitive crops. May be repeated once
as required by weed growth.
E. Spot treatments to control emerged annual and perennial grasses.
RECOMMENDED
"Dowpon"
SUGGESTED
"Urox 114o"
7 to 10 lb.
per 100 gal.
water.
3/4 ounce or
20 grams per
square yard.
Apply as light foliage wetting spray to clumps or
individual plants of annual or perennial grasses,
especially Napiergrass, paragrass, Bermudagrass,
barnyardgrass, wild sorghum, Alexandergrass, crab-
grass, goosegrass and others. These "spot sprays"
should be applied 1 or 2 times. Hand gun booms may
be fitted with inverted funnels which can be used
to push cane leaf cover aside.
Distribute uniformly over Napiergrass stools in
spring ratoon growth as soon as Napiergrass can
be distinguished from sugarcane. Urox is a soil
sterilant at this application rate and will injure
or kill sugarcane immediately adjacent to treated
grasses. Do not apply more than 25 pounds per acre
of sugarcane. "Urox 22%" may be used at one-half
the rate indicated.
F. For emerged broadleaf weeds:
RECOMMENDED
For 2,4-D susceptible weeds: 2,4-D up to 2 lbs/A Amine salt preferred
For 2,4-D resistant weeds (d.og fennel, ground cherry, nightshade, ragweed):
2,4-,5-T up to 1 lb/A Amine salt preferred
or
silver up to 1 Ib/A
For mixed broadleaf weeds: 2,4-D + 2,4,5-T at 3/4 lb/A each in tank mixture.
For pe9litoryweed (artilleryweed)
a. "Atrazine", "Karmex" or "Telvar" at 1/2 to 3/4 lb/A
plus
b. 2,4-D amine at 1/2 Ib/A
plus
c. Surfactant at 1/2 to 1% by volume
Note: The 2,4-D component may be omitted in fields near sensitive
crops or where other broadleaf weeds are not a problem.
These combinations should be applied with directional spray
equipment.
a- For mixed annual grass and broadleaf weeds:
For small seedling weeds: Use "D" recommended or "D" suggested combinations
above.
For larger establhsherl weeds: Use "Dowpon" plus 2,4-D as "D" and "F" above.
-6-
GLOSSARY AND STATUS OF HERBIbIDES FOR SUGARCANE
Chemicals recommended or suggested for Florida.
Atrazine 2-chloro-4-ethylamino-6-isopropylamino-S-triazine. Geigy "Atrazine
80W" an 80% wettable powder. Maximum cleared rate: 5 lb/A per
application, 12-1/2 lb/A per crop.
DoWpon Sodium salt of 2,2-dichloropropionic acid. Dow "Dowpon", 74% acid
equivalent. Maximum cleared rate 11.1 lb/A acid equivalent. Effective
against established grasses. Should be used in repeated or split
applications.
2,4-D Amine salt formulations of 2,4-dichlorophenoxyacetic acid containing
4 lb/gal acid equivalent. Treatment rates must be adjusted for 6 lb/
gal formulations. Many suppliers. Maximum cleared rate 2 Ib/A acid
equivalent applied prior to cane emergence or postemergence until
layby. Use caution to prevent damage to nearby sensitive crops.
Fenac Sodium salt of 2,3,6-trichlorophenylacetic acid. Amchem "Fenac"
containing 1.5 lb/gal acid equivalent.
Karmex diuron, 3-(3,4-dichlorophenyl)-l,l-dimethylurea. duPont "Karmex",
an 80% wettable powder. Maximum cleared rate for Florida is 4 lb/A
preemergence to weeds after planting with additional postemergence
sprays to a maximum of 6 lb/A.
Randox CDAA, 2-chloro-N,N-diallylacetamide. Monsanto "Randox" containing
4 lb/gal active. Maximum cleared rate is 10 Ib/A: do not apply more
than once per crop nor within 10 months of harvest. Monsanto "Limit"
contains Randox and 2,4-D acid.
Silvex Low volatile esters of 2-(2,4,5-trichlorophenoxy) propionic acid.
Formulations containing 4 lb/gal acid equivalent are available
from Amchem, Chipman and Dow. Cleared from Florida at 1.5 lb/A
broadcast with second application before cane is 3- feet tall.
Cleared for use in Louisiana only at l- lb/A acid equivalent
preemergence to cane and weeds or after off-barring and until cane
reaches 3 to 32 feet tall. Cleared for use in Hawaii only at 5 lb/A
acid equivalent preemergence after planting or ratooning and bef-vife
cane emergence. Use is limited to 2 applications per crop. Pre-
cautions similar to 2,4-D and 2,4,5-T are required.
Surfactant non-ionic surfactant, Triton X-100, or others of similar activity.
Telvar monuron, 3-(p-chlorophenyl)-l,l-dimethylurea. duPont "Telvar",
an 80% wettable powder. Cleared rate same as for "Karmex".
2,4,5-T tnmine salt formulations of 2,4,5-trichlorophenoxyacetic acid
containing 4 Ib/gal acid equivalent. Treatment rates may be adjusted
when 6 lb/gal formulations are used. Many suppliers. Rate of 1 Ib/A
acid equivalent cleared for postemergence use in established cane up
to 2 feet tall. Use caution to avoid damage to nearby susceptible
crops.
Urox monuron TCA. Allied Chemical "Urox 11 Weed Killer", an 11if granilar
formulation. Also available in a 22o granular formulation. This
is a soil sterilant formulation not cleared for crop use.
Cleared chemicals not suggested for Florida.
PCP or Pentachlorophenol. Available from several suppliers. Cleared at
Penta 4.5 Ib/A when used preemergence to 'cane at 1 to 2 days after
planting. Cleared at same rate for directed postemergence sprays
before weeds are 2 inches tall.
NaICP or Sodium salt of pentachlorophenol. Available from several suppliers.
SFCP Cleared at 44 lb/A preemergence immediately after planting and before
weed seedlings emerge. A rate of 10-2 lb/A is cleared for use
immediately after weed seedlings emerge.
ry.~~ine a2-hloro-4,6-bis(ethylamino)-s-triazine. Geigy "Simazine 80s",
an 80% wettable powder. Application- rates and conditions similar
to Atrazine.
TCA, NnTCA or Sodium salt of trichloroacetic acid. Available from many
,_cA suppliers in formulations containing about 80% TCA equivalent.
lJe.red at 31.7 lb/A for pre-and early postemergence and at 45 lb/A
aW-id equivalent as late postemergence directed sprays at base of
'cane plants.
2,4,5-T As given above. Cleared at 4.5 lb/A acid equivalent for preemergence
use in IHawaii only.
SHORT GLOSSARY OF HERBICIDE TERMINOLOGY
Band application Using the herbicide in a narrow, continuous strip in, over
or along the crop row rather than over the entire field.
Broadcast application Using the herbicide over an entire field or area.
Contact herbicide An herbicide that kills primarily by direct contact with
plant tissue rather than by translocation within the plant.
Directed application Using an herbicide in a restricted location such as the
crop row or bed at the base of plants to avoid wetting plant foliage.
Overall application Applying an herbicide from directly above plants.
Postemergence treatment Application after crop plants emerge. Treatments may
also be specified as postemergence to weeds or both crop and weeds.
Preemergence treatment Application after a crop is planted but before it emerges.
Treatments may be specified preemergence to weeds or both crop and
weeds. Treatments may be specified preemergence to weeds but post-
emergence to the crop. Usually, preemergence treatments are made
before both crop and weeds emerge. Contact preemergence treatments
kill emerged weeds by contact action and are applied before the crop
comes up. Residual preemergence treatments kill weeds as their seed
germinate or as seedlings emerge, either before or after crop coming-up.
Preplanting treatment Application of an herbicide before planting a crop.
USE CAUTION WHEN APPLYING 2,4-D and 2,4,5-T
Chlorophenoxy herbicides are capable of causing severe injury to sensitive
vegetable, fruit and ornamental crops several miles from the actual spraying
site. The degree of hazard in the use of these chemicals is related directly
to the manner of application and weather conditions. Aerial application is
most hazardous. Ground eqlta.pmr should. he oh-rat efl Vwit low spray volunce and
at low spraying pressure.
Not more than 10o of a farm unit should be treated per day. Chlorophenoxy
herbicides should not be applied within one-half mile of susceptible crops
except under the most carefully controlled and supervised conditions. These
chemicals should not be applied when wind velocity exceeds 8 mph in isolated
areas nor when wind exceeds 4 mph when sensitive crops are grown less than 2
miles downwind. The safest formulations are the salts, particularly amine
salts. The above rules-of-thumb are guides not guaranteed for prevention of
damage. For more detailed information refer to Mimeo Reports EES64-12 and
EES65-21.
READ THE LABEL
Labels on herbicide containers should be read and understood prior to use
of the chemical contained therein. This is the final and most appropriate guide
to economical and successful chemical usage.
EQUrlIMrT FOR SUGARCANE HERBICIDE APPLICATION
A separate mimeographed report, EES64-9, contains information on basic
spraying equipment, calibration, shielded sprayer design and methods of
application. Callbration procedures are detailed in Florida Extension
Circular 275A.
EES67-3
500 copies
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