1. Herbicides for Sugarcane
Calvin Odero
Everglades REC
Belle Glade

2. Herbicide Basics What is the application timing
Common sugarcane timing
Preemergence (PRE)
Applied prior to weed and crop emergence
Generally soil active herbicides (some exceptions)
Postemergence (POST)
Applied after weeds have emerged
Can be early, mid, late
Generally over-the-top
Generally more foliar active herbicides

3. Herbicide Basics What is the application timing
Common sugarcane timing
Post-Direct/Lay-by
Applied after sugarcane is fairly large
Direct herbicide at base of plant
Generally for herbicides that cause crop injury
Can be foliar or soil active (or both)
Non-Crop/Fallow
Generally foliar active
Can help with hard to control weeds

4. PRE Herbicides

5. Atrazine Backbone of sugarcane weed control Used both PRE and POST PRE
Good soil activity (2-4 qt/A)
Controls most broadleaves
Suppress/control certain grasses
Activity begins to fade 3-5 weeks after application
Broadleaf activity last longer than grass activity

6. Evik (Ametryn) Generally applied POST, but some PRE
Controls many small grasses and broadleaves
Weeds need to be less than 4 inches
Less than 3 inches for alexandergrass
Crop injury
More common with higher rates and warmer temperatures

7. Evik (Ametryn) Rates Tankmixture: 0.5-1.5 lb/A (labeled)
Lower rates often used
Efficacy?
Tankmixture:
Often tank mixed with atrazine (2-4 lb/A) at 0.25 to .75 lb/A

8. Prowl H2O (Pendimethalin)
Used on moderate acreage
Excellent grass control
Can be season-long under good conditions (incorporation by rainfall)
Not so good on broadleaves
Tank-mix with metribuzin helps
Still may need follow-up for spiny amaranth

9. Prowl H2O (Pendimethalin)
Challenges
Needs rainfall/soil moisture for activity
Can be good when soil is moist
More consistent when soil moisture is good
Rates
Sand
qt/A
Muck
qt/A

10. Prowl + Metribuzin Good broad spectrum PRE program Rates
Muck soil only!!!
Ideally, don’t cultivate if there aren’t weeds
Some broadleaves can come through
Spiny amaranth
Expensive
Can be very good with good soil moisture
Rates
Prowl (4 qt/A)
Metribuzin (1 lb/A)

11. K4 Registered for FL sugarcane in 2005
Mixture of hexazinone (Velpar) and diuron (Karmex)
Applied at 2-4 lbs/A
Higher rates for muck soils, lower on sand
Good control of many grass and broadleaf weeds
Can go out early POST
Apply to cane less than 18 inches tall
Not currently used in Florida

12. Diuron (Direx, others) Not used much Rate
Sand soils (binds very strongly on muck)
Better control of broadleaves than grass
Not much experience
Crop injury?
Rate
1.6 lb/A PRE

13. Glyphosate (several trade names)
MUST BE APPLIED PRIOR TO CANE EMERGENCE!!!!!!!!
Excellent control of emerged weeds
Excellent control of sugarcane if emerged!
Timing is very, very critical
Controls some hard to manage species
Bermudagrass
Paragrass
Rate
qt/A

14. Valor (Flumioxazin) PRE/POST-Direct
Good broadleaf control PRE
Grass control has been variable
Active POST on small grass and broadleaves
High levels of burn on sugarcane
Post-direct only
Cannot be applied over the top of sugarcane
Not currently used in Florida

15. POST Herbicides

16. Atrazine POST Use with crop oil concentrate Rate still 2-4 qt/A
Controls many small broadleaves
Grass needs to be small
3 inches of less is ideal
Provides residual activity

17. Envoke (Trifloxysulfuron)
Applied at 0.3 to 0.6 oz/A
POST, ratoon sugarcane only
Excellent nutsedge product
Good control of small broadleaves
Controls some small grasses
Excellent on alligatorweed, spiny amaranth
Looks good in combination Asulox/Asulam at 0.5 gallon/A for fall panicum control
Good, wide spectrum treatment

18. 2,4-D Amine Very versatile, useful product Controls most broadleaves
Can use lower rates on smaller weeds
Can suppress nutsedge growth
Probably not long-term control
Alligatorweed activity can be good
Need good conditions for best control

19. 2,4-D Amine Challenges Can drift and volatilize Major problems!!!!
Follow the Florida Organo-Auxin Rule
No volatile formulations (esters)
Application restrictions based on wind speed
Also distance from sensitive crops

20. 2,4-D Amine Rates 0.5 to 2.0 lb ai/A
Note rates in ai due to many formulations
Lower end will control many small weeds
Higher rates for alligatorweed, large weeds
For vine control later in the season

21. Asulox (Asulam) Excellent POST grass herbicide
Controls most common grasses
Size of weeds is important
Can use 6 pt/A if grass is 6-8 inches or less
Preferably less!
Use 1 gal/A (8 pt) is grass is greater than 8 inches
Use a surfactant (0.25% v/v) or COC (1% v/v)

22. Asulox (Asulam) Challenges Good spray coverage is very important
Many control issues relate to coverage
Use the proper rate
If it’s 6 inches today, it will probably be 8 inches next week
Slow activity
Need to be patient
Injury
We can see burning to leaves at higher rates
Can use a directed application

23. Asulox (Asulam)

24. Evik (Ametryn) Controls many small grasses and broadleaves
Needs to be less than 4 inches
Less than 3 inches for alexandergrass
Directed application
Injury will be seen on treated foliage
Use surfactant at 0.5% v/v
Rates
lb/A
Lower rates (0.25 lb/A) often used
Efficacy?

25. Sandea (Halosulfuron)
Excellent nutsedge control
Yellow and purple (4-12 inch ideal)
Works best under good moisture conditions
Controls some small broadleaves
Small pigweed, ragweed (less than 4 inches)
Use surfactant or COC
% v/v surfactant or 1% COC v/v
Rate
1 to 1.33 oz/A

26. Callisto (Mesotrione)
Applied POST at 3 fl oz/A for broadleaf weed control
Reduces atrazine dependence
May reduce the need for 2,4-D
Reduces amount of herbicide applied per acre
Minimizes broadleaf weed escapes

27. Callisto (Mesotrione)
Low use rate
Greatly reduces chemical storage, transportation and handling
1 gal of Callisto (3 fl oz rate) will treat 42 acre
Takes 31.5 gals of Atrazine 4L (3 lb ai/A rate) or 35 lbs of AAtrex Nine-O to treat 42 acres
Reduces container disposal, handling
Reduces environmental risks
Tank-flexibility
Tank-mix with Atrazine 4L (1 qt/A) or Aatrex Nine-O (1.1 lb/A), Evik ( lb/A)
Envoke, Asulam

28. Fallow Land Treatments

29. Glyphosate Excellent control of emerged weeds
Controls many hard to manage species
Bermudagrass
Paragrass
Napiergrass
Nutsedge (better on yellow)
Many, many others

30. Take Home Always follow the label!!! Several effective herbicides
Identify weed spectrum
Apply correct rate
Apply to correct weed size
Let the herbicide work!
We will hopefully have more options in the future!

31. Contact Information
Calvin Odero Extension Weed Specialist & Assistant Professor Everglades Research & Education Center 3200 E Palm Beach Road Belle Glade, FL Phone: