1. Weed Management Update
Larry Binning and Tim Trower
University of Wisconsin
Joe Bollman
UWEX- Columbia County
2. Topics
• New Herbicides
• Label changes
• Synthetic Auxin herbicides for soybeans-
where are we now?
• Resistance update
• Dandelion control
3. New Herbicides
What’s Up?
• No new Modes of Action on the horizon
– Last new MOA were the HPPD’s in the 1990’s:
• Callisto, Laudis, Impact
– Companies are still screening but introducing
new herbicides are complicated by:
• Stringent environmental laws
• Costs
– Heavy effort in seed trait technology
• Using existing herbicides
4. New Herbicides
What’s Up?
• Long story short:
We need to protect our current herbicide
portfolio from resistance!
(No silver bullet on the horizon)
5. Realm Q
DuPont
• Premix containing rimsulfuron, mesotrione
and the safener isoxadifen
– Two MOA’s: ALS and HPPD inhibitors
• Formulated as a WDG
• Application rate of 4 oz/a will provide:
– 1.2 oz/a of rimsulfuron
– 2.5 oz/a of mesotrione (equivalent to 2.5 fl oz/a of
Callisto)
6. Realm Q
DuPont
• Apply postemergence:
– After corn emerges but before corn reaches 20” or 7
leaf collars
• Adjuvants are required unless tank mixed with a
fully-loaded glyphosate formulation
• Can be used alone, in a sequential program or
tank mixed with glyphosate and many other
herbicides
– Third MOA for resistance management
• Registration is pending
7. Results- Arlington
Rate Percent Control Yield
Treatment (rate/a) Timing G. foxtail C. lambs Velvet Dandelion (bu/a)
Realm Q + 4 oz Post 100 100 100 88 203
COC+AMS 1% + 2 lb
Cinch ATZ fb 1 qt Pre 100 100 100 93 213
Realm Q + 4 oz Post
COC+AMS 1% + 2 lb
Realm Q + 4 oz Post 100 99 100 95 213
Abundit 32 fl oz+
AMS 2 lb
Realm Q + 4 oz Post 100 100 100 95 219
atrazine + 0.5 lb
COC+AMS 1% + 2 lb
Nontreated 0 0 0 0 151
Preemergence treatment applied May 4.
Total post treatments applied on June 1.
Sequential post treatment applied June 13.
8. Authority XL
FMC
• Premix containing sulfentrazone and
chlorimuron ethyl
– Two MOA’s: PPO and ALS inhibitors
• Formulated as a DG
• Soil applied only
– Application rates are dependent on soil texture
and pH
– 4 oz/a provides 0.155 lb ai Authority and 0.02 lb ai
of Classic (medium soil rate)
9. Authority XL
FMC
• Use as part of a planed sequential program in RR
or LL soybeans
– Can not use full rates in Wisconsin
• Will provide good early-season control of most
broadleaf weeds and grasses
• Soil pH will influence crop rotation interval, check
the label before using!
– pH less than 6.8: corn- 10 months
– pH greater than 6.8: corn- 18 months
• Registered
10. Results- Arlington
Rate Percent Control Yield
Treatment (product/a) G. foxtail C. lambs Velvet R. pigweed C. ragweed (bu/a)
Authority Broadleaf 4 oz 75 100 90 100 100 46
Authority First 4 oz 64 93 100 98 100 45
Authority Assist 4 fl oz 84 100 95 100 100 46
Nontreated 0 0 0 0 0 16
All products applied preemergence
Rates represent the set-up rate for each product
Evaluated prior to glyphosate application
11. Warrant
Monsanto
• Formally know as MON63410
• Encapsulated acetochlor
• Labeled for postemergence use in soybeans
and field corn
– Do not use on sweet corn
– Does not contain the safener; do not use prior to
crop emergence
– Corn- up to 30 inches
– Soybeans- up to R-2
12. Warrant
Monsanto
• Do not apply with liquid fertilizer as a carrier
• Will not control emerged weeds:
– Can be tank mixed with glyphosate on RR corn
and soybeans only
• Will provide residual control of most annual
grasses and control/suppression of some
annual broadleaves
• Registered
13. TripleFLEX
Monsanto
• Premix of acetochlor, flumetsulam and
clopyralid
– Three MOA’s: cell division, ALS and synthetic auxin
• Labeled for use on herbicide tolerant field and
silage corn
• A rate of 1.5 pt/a provides:
– 0.88 pt/a Surpass, 2.3 fl oz Stinger and 0.45 oz
Python
– Same ratios as SureStart
14. TripleFLEX
Monsanto
• Can be used ppi, pre or postemergence
• Can be tank mixed with glyphosate
– Use a RR hybrid if using postemergence
• TripleFLEX is one component of resistance
management
• Registered
15. Callisto Xtra
Syngenta
• Premix of mesotrione and atrazine
– Two MOA’s: HPPD and photosystem II
• For postemergence use on corn
(field, seed, sweet, silage and yellow popcorn)
– Up to 12 inches in height
• A rate of 20 fl oz will provide:
– 2.5 fl oz Callisto and 0.5 lb atrazine
16. Callisto Xtra
Syngenta
• Restrictions:
– Do not tank mix with certain EC grass herbicides
– Do not apply to crop treated with Counter or Lorsban
– Do not tank mix with OP or carbamate insecticides
– Do not use liquid fertilizers as the carrier
• Will control most annual broadleaves and many
small grasses
– Many tank mix options including glyphosate on RR
corn
– Registered
17. Fierce
Valent
• Premix of pyroxasulfone (KIH-485) and Valor
– Two MOA’s: PPO and seedling shoot inhibitor
• Formulated as a 76% WDG containing 33.5%
Valor and 42.5% pyroxasulfone
• Rate is soil dependant
– Medium soil rate of 3.75 oz/a contains:
• 2.5 oz Valor and 1.88 oz pyroxasulfone
• Preemergence in soybeans
18. Fierce
Valent
• Seven days pre-plant in no-till or reduced till
field corn
• Pyroxasulfone has provided very good annual
grass control and crop safety in trials at the
Arlington station
– Evaluated since 2006
• Component of a planned sequential weed
control program
• Registration expected mid-to-late 2011
19. Results- Arlington
Rate Percent Control Yield
Treatment (product/a) G. foxtail C. lambs Velvet C. ragweed (bu/a)
Valor 2 oz 81 100 98 94 60
Fierce 3 oz 98 99 100 100 61
Fierce 3.75 oz 99 99 100 100 62
Nontreated 0 0 0 0 33
All products applied preemergence
Evaluated prior to glyphosate application
20. Other Updates
• Integrity (BASF) is now Verdict
– Soybean has been added to the label
• 5 oz/a: Outlook at 4 fl oz and Sharpen at 1 fl oz
– Corn use rate has expanded
• Coarse: 10-12 fl oz
• Medium: 13-15 fl oz
• Fine: 16-18 fl oz
– Burndown applications:
• Always add glyphosate
• Use MSO and AMS or 28% UAN
21. Other Updates
• Impact (AMVAC)
– Increase maximum rate to 1 fl oz/a in a single or
sequential application
– Added fall panicum, yellow foxtail and woolly
cupgrass as controlled IF applied prior to grasses
exceeding 3 leaves.
– Crop rotation restrictions:
• wheat, barley, oats and rye- 3 months
• alfalfa, potato, soybean and sunflower- 9 months
• all other crops- 18 months
22. Other Updates
• Impact (cont.)
– Dry beans and snap beans can be rotated at 9
months when using 0.5 fl oz/a
• Basis (DuPont)
– Soybean rotation has been reduced to 15 days if
using the 0.33 oz/a rate
– Remains 10 months for rates greater than 0.33
oz/a
23. Synthetic Auxin Herbicides
“Back in the Saddle Again”
• DHT from Dow
– Dow AgroSciences Herbicide Tolerance Trait
• Provides tolerance to post applied 2,4-D
– Glufosinate tolerance in soybeans and “fop” grass
herbicide tolerance in corn
• Developing technologies to mitigate off-target
concerns and decrease potential for off-target
movement
• Commercial launch:
– Corn: 2013
– Soybeans: 2014
24. Synthetic Auxin Herbicides
“Back in the Saddle Again”
• Dicamba tolerant soybeans from Monsanto
• Provides tolerance to post applied dicamba
• Working in partnership with BASF to develop
technology to reduce off-target movement
• Commercial launch unknown
– Earliest expected is 2015
BUT
25. Synthetic Auxin Herbicides
“Back in the Saddle Again”
• Dicamba tolerant soybeans will not be
tolerant to 2,4-D applications and visa-versa
• Technology brings another tool to combat
resistance but will require vigorous
stewardship
• Phenoxy off-target movement is on the EPA’s
radar screen………………..
27. Resistance to Glyphosate in Wisconsin
• No confirmed resistance of giant ragweed,
common lambsquarters, or waterhemp
• Variability in control has been observed at
reduced rates
• Seed from two susceptible giant ragweed
populations (Rock & Grant Co.) are being
evaluated for resistance
28. Resistance to HPPDs
• Callisto, Impact and Laudis
– Newest mode of action (MOA) on market
• Latest MOA with confirmed resistance in U.S.
• Waterhemp-Iowa, Illinois
29. Herbicide Resistance Weeds of the Midwest
Wisconsin Iowa Illinois Minnesota
Giant Foxtail ACCase, ALS PSII, ACCase - ALS
Lambsquarters PSII PSII PSII PSII
C. Ragweed - - ALS ALS
G. Ragweed - ALS, Gly ALS Gly
Waterhemp ALS ALS, PSII, HPPD, ALS, PSII, HPPD, Gly
PPO, Gly PPO, Gly
Velvetleaf PSII - - PSII
ACCase---Select, Poast, Fusion ALS---Harmony GT, FirstRate
PSII---atrazine, Sencor PPO---Reflex, Valor
HPPD---Callisto, Impact, Laudis Gly---Roundup
Once a population becomes resistant to a MOA, it is always resistant!
30. Dandelions
“What was old is new again”
• Increasing problem in many cropping systems
• Reduced tillage and less phenoxy herbicide use
may be a contributing factor
• Glyphosate controls seedlings but is less effective
on mature plants
• We have conducted several studies over the past
three years on the most effective treatments
• Research is continuing on herbicides and timings
31. Dandelion Control
Fall applied and evaluated the following spring
2,4-D @ 32 fl oz +
Nontreated PowerMax @ 21 fl oz
Synchrony @ 0.375 oz/a +
2,4-D @ 16 fl oz + Enlite @ 2.8 oz/a +
PowerMax @ 21 fl oz PowerMax @ 21 fl oz
32. TABLE 1: Control of dandelions with common fall and spring burndown applications
Percent Dandelion Controla
Treatmentb Rate Fall Applied Spring Applied Plant-back restrictions
(unit/A) Evaluation Timing corn soybeans
Early Late Early
Octe Octe
Mayc Mayd June (days)
2,4-D LVE + 16 fl oz +82 42 3 72 40 7 14
Roundup PowerMax 21 fl oz
2,4-D LVE + 32 fl oz + 76 44 15 Not applied 14 14
Roundup Original 24 fl oz
Distinct + 2 oz + 73 57 48 Not applied 14 30
Roundup Original + 21 fl oz +
2,4-D LVE 16 fl oz
Valor + 2 oz + 82 39 20 Not applied 30 14
Roundup PowerMax 21 fl oz +
2,4-D LVE 16 fl oz
Canopy EX + 1.1 oz + 95 87 93 70 53 9 months 14
2,4-D LVE 16 fl oz
Autumn + 0.3 oz 91 75 48 Not applied 30 90
Roundup PowerMax 21 fl oz
Synchrony + 0.375 oz 90 40 28 81 66 9 months 14
Roundup PowerMax + 21 fl oz
2,4-D LVE 16 fl oz
Enlite + 2.8 oz + 91 43 5 86 71 9 months 0
Roundup PowerMax 21 fl oz
Express + 0.25 oz + 93 65 51 Not applied 14 14
Roundup PowerMax + 21 fl oz +
2,4-D LVE 16 fl oz
a
-Data average from 2009 and 2010 results at Arlington, WI
b
- Recommended adjuvants were added to all treatments
c
- Coincides with corn planting
d
- Coincides with soybean planting
e
- Data from 2010 only; All plots received a broadcast treatment of glyphosate in June. Typical when
growing glyphosate resistant crops.
33. Summary
• While fall applications of 2,4-D and glyphosate can provide good control
by the time that corn is planted, control quickly drops by the end of May
when soybeans are planted. In 2010 control from fall applications was
essentially zero by the following fall even after an in-crop glyphosate
application. This suggests that addition measures need to be taken to
reduce weed populations.
• Delaying applications of glyphosate and 2,4-D into spring can provide
some decent suppression for 1-2 months as table 1 shows, but dandelions
recovered by mid season and perennial plants are often not killed. This
can result in an increase in old plants which will be more difficult to
control.
• Application of residual herbicides can extend control into mid-
summer, and sometimes even for one year. We observed Canopy
EX, Enlite, and Synchrony all provided good suppression of seedling and
perennial dandelions through mid-summer unlike other treatments.