1. What’s Happening in Weed Control 2001
Dr. Eric P. Prostko
Extension Weed Specialist
Tifton
Certified Crop Advisors Meeting, Dec 15, 2000, Tifton GA

2. Topic for Discussion
2000 Problems
peanuts
cotton
corn
soybeans

3. How dry was it??? May Precipitation in Georgia
85-90% of GA peanuts were planted in May

4. Drift Problems in 2000
Staple Plus on Sorghum
Roundup on Peanuts

5. Top 10 Tips For Reducing Pesticide Drift Problems
nozzle selection
reduce pressure
lower boom height
increase nozzle size
avoid spraying when winds exceed 10 MPH
lookout for inversions
use additives
calibrate sprayer
keep records
use common sense

6. “The Year of the Pigweed”
dry weather
incorporation
big weeds
Palmer amaranth
resistance??

7. Palmer Amaranth Control with Blazer Applied at Different Timings
Mayo et al (KS)

8. Pigweed Control with Blazer and Classic - 28 DAT
Gossett and Toler, 1999 (SC)
Applied at V3-V4 stage

9. Pigweed Identification World Wide Web
Iowa State University
* waterhemp/default.htm
Kansas State University *

10. PEANUTS

11. 11% of peanut market
in southeast

12. How would you rate the overall performance of Strongarm in your county?
2000 UGA County Agent Survey

13. What were the weeds that most frequently escaped control of Strongarm?
2000 UGA County Agent Survey

14. Strongarm - Does it work in GA? Attapulgus - 7 WAP
Strongarm + Prowl
(PPI)
Untreated

15. Variety Tolerance to Strongarm (PRE) Tifton, GA 2000
Weed-free test
Averaged over 2 varieties (GA Green, C99R)
LSD = 561

16. Strongarm How Should It Be Used in GA?
use where starbur, eclipta, and copperleaf are problems
tank-mix with DNA
irrigate in if possible
variable on nutsedge
poor sicklepod control

17. Strongarm Label Update 2001
“at cracking” applications
Snapbean rotation = 9 months

18. Valor 50WDG Valent introduced in 1989 flumioxazin
N-phenylphthalimide derivative
PPO oxidase inhibitor
PRE
2-3 ozs/A
label in 2001 (I hope!!)

19. Why do we need Valor?? Florida beggarweed rotation restrictions
mode of action
reduced costs/A?

20. Although Valor has many strengths, growers/dealers need to be made aware of its weaknesses such as
cocklebur
nutsedge
sicklepod
increased crop injury with delayed applications

21. Other Peanut Weed Control Issues
paraquat formulations
* Starfire (old)
* Gramoxone Max
* Boa
Ultra Blazer
* sodium salt vs. amine formulation
* less peanut injury???

22. COTTON

23. GMO Cotton Varieties in GA
Source: NASS, June 2000

24. Top 12 Varieties in 2000 GA Crop

25. Roundup Ready Programs

26. Glyphosate formulations (labeled for OT uses on RR cotton)
* not Touchdown 5L

27. Glyphosate is a good herbicide but it does have some weaknesses such as …..
morningglory
nutsedge
dayflower
hemp sesbania
prickly sida
Florida pusley

28. Say Bye Bye to Bladex (cyanazine)
no sales or distribution after 9/30/02
cannot be used after 12/31/02
Does anyone have some??

29. Cyanazine Replacements
Goal
Harvade
Valor
glyphosate
diuron
prometryn
fluometuron
Cobra

30. Cyanazine Replacements Issues
Contact activity (CoA)
Residual activity (R)
Carryover potential (CaP)
Injury potential (I)
Cost ($)

31. Cyanazine Replacements Strengths / Weaknesses
diuron -- CoA, R, I, $ / CaP?
prometryn -- CoA, R, CaP, I, $
fluometuron -- R, I, $ / CoA, CaP?
Cobra -- CoA, CaP, I / R, $
Goal -- CoA, CaP, I / R, $
Harvade -- CoA, CaP, $ (IPOZZ) / R
Valor -- CoA, R, CaP / I, $? experimental
Glyphosate -- CoA, CaP, $ / R only RR

32. Conventional Programs

33. CORN

34. Weed Control in Corn numerous options
tough to beat atrazine + cultivation ($$$)
Prowl and/or Accent for PANTE
need something for late-season MG

35. Weed Control in Corn New Stuff
herbicide resistant hybrids
* cost/A
* hybrid performance
* 6% of U.S. crop
* GMO Issue
new labels

36. Herbicide Resistant Corn Hybrid Technologies Cost/A

37. Herbicide Resistant Corn Hybrids in GA - 2000
hybrids that performed equal to or better than the test averages included the following:
* Pioneer 32K63LL (Liberty)
* Garst 8222 IT (Clearfield)
* Dekalb 626RR (Roundup)

38. Weed Control in Corn New (er) Labels
Accent Gold
Action
Axiom
Axiom AT
Aim
Balance
Celebrity Plus
Distinct
Degree Extra
Epic
Northstar
Spirit

39. SOYBEANS

40. GA Soybean Production 1989-2000
Source: GASS

41. Weed Control in Soybeans Roundup Ready Tank-Mixes
oz/A ($3.14)
ozs/A ($3.11)
4 ozs/A ($4.30)
improved control of morningglory (5-10%)
mixed results across southern US
cheaper than split applications of Roundup but not as effective

42. Newer Roundup Premixes Soybeans
BASF
Extreme
* Roundup (2 lb/gal) + Pursuit (0.17 lb/gal)
Backdraft
* Roundup (1.25 lb/gal) + Scepter (0.25 lb/gal)
knockdown + residual
NIS + N required on label

43. Roundup/Boron/Dimilin Tank Mixes??
full-bloom to early pod-fill
R2-R3 stage
Is this the best time for Roundup?
Crop injury?
Need more data

44. Soybean Yield Response to Roundup/Boron/Dimilin Tank-Mixes Hartz 7550RR
Bu/A
Tifton, GA 2000
P = 0.85
CV = 23

45. Weed Control in Soybeans Other New(er) Stuff
Action
Axiom
Boundary
Detail
Domain
Expert
Pendimax
Raptor
Resource

46.
University of
Georgia
Extension
Weed Science