The Ongoing Battle with Weeds

Transcription

1 The Ongoing Battle with Weeds

2 Current Weed Control Issues Pigweed Control Herbicide Resistant Weeds New Weed Control Technologies

3 Glyphosate Resistant Palmer amaranth in Soybeans

4 Glyphosate Resistant Waterhemp in Eastern Kansas

5 Weed Management Theme for 2017 Multiple Pronged Approach Cultural practices Sequential herbicide programs Residual herbicides Multiple herbicide sites of action Timing, Timing, Timing!

6 Maximum growth stage/height label guidelines for postemergence waterhemp and Palmer amaranth control. Herbicide Rate Waterhemp Palmer Amaranth Cobra 12.5 oz 6 lf/3 in 6 lf/3in Ultra Blazer 1.5 pt 6 lf/4 in 6 lf/4 in FlexStar/Reflex 1 pt 2 lf 4 lf FlexStar GT 3.5 pt 2 in 1 in Marvel 7.25 oz 4 in 3 in Liberty 29 oz 5 in 4 in Cadet 0.9 oz 2 in --

7 Growth of Palmer Amaranth with 5 days of Hot Weather June 15 June 20

8 New Technologies for Soybeans New Herbicides Zidua Pro Proliferation of generics: fomesafen, aciflourfen, flumioxazin, glufosinate New Trait Technologies Xtend Soybeans Enlist Soybeans HPPD Soybeans

9 Zidua Pro (BASF) Premix containing 2.28 lb pyroxasulfone (Zidua, 15), 1.33 lb imazethapyr (Pursuit, 2), and 0.48 lb saflufenacil (Sharpen, 14) per gal. Fall, Preplant, or PRE to soybeans Rates: 4.5 to 6 oz/a Adjuvants: MSO and N fertilizer source for burndown activity. Do not plant wheat for 4 Mo; corn for 8.5 Mo; Clearfield Sunflower for 9.5 Mo; alfalfa for 10 Mo; Clearfield canola for 12 Mo; or cotton, oats, sorghum or sunflower for 18 Mo after application.

10 New Seed Technologies in Soybeans No new novel herbicide modes of action or active ingredients on the near horizon Crops stacked with multiple traits Dicamba resistant soybeans (Xtend) from Monsanto 2,4-D resistant soybeans (Enlist) from Dow HPPD resistant soybeans from Bayer and Syngenta

11 Roundup Ready 2 Xtend Soybeans Soybeans that contain a gene that confers resistance to dicamba stacked with the Genuity Roundup Ready 2 trait technology. Resistant gene isolated from a soil bacteria. Resistance is based on metabolism of dicamba by soybeans. New dicamba formulations specifically for RR2X soybeans. Traits and some herbicides finally approved. XtendiMax and Engenia recently approved for RR2X soybeans.

12 Dicamba Products for Xtend Crops New low volatile formulations of dicamba have been developed by industry, which will be the only dicamba products labeled on Xtend crops. Monsanto dicamba products for Xtend soybeans Xtendimax new dicamba product with Vapor Grip Technology Roundup Xtend Glyphosate + dicamba premix with Vapor Grip DuPont dicamba product for Xtend soybeans Fexapan same formulation as Xtendimax BASF dicamba product for Xtend soybeans Engenia new dicamba BAPMA salt Standard rate of dicamba will be 0.5 lb ae/a

13 Xtendimax and Engenia Label Guidelines for use on Xtend Soybeans Rates: Xtendimax: 22 to 44 oz Pre, 22 oz Post Engenia: 12.8 to 25.6 oz Pre, 12.8 oz Post Timing: preplant through R1 soybeans before weeds exceed 4 inches tall Do not tank-mix with any other herbicide Only apply with approved adjuvants Do not apply with Ammonium sulfate

14 RR2X Soybean Response to Dicamba several hours after treatment

15 Weed control in Xtend soybeans, Manhattan, KS, 2016 (Peterson and Thompson). Herbicide Rate Paam Vele (% control)----- Roundup Pmax+dicamba 32oz+0.5lb Fierce/RU Pmax+dicamba 3oz/32oz+0.5lb Auth Elite/Pmax+dicamba 25oz/32oz+0.5lb Boundary/Pmax+dicamba 2pt/32oz+0.5lb Rowel+Warrant/Pmax+dic 2+64oz/32oz+0.5lb LSD (5%) 4 NS Planted & PRE 6/1, poor Pre activation; Post treatments 6/20, Paam~10

16 RR2 Xtend Soybeans Roundup PowerMax + Dicamba (P)

17 RR2 Xtend Soybeans Fierce XLT (PRE) fb Roundup PM + Dicamba (P)

18 Weed control in different soybean systems at Manhattan, KS, 2016 (Peterson and Thompson). Herbicide Trait Rate Injury Paam Vele Ilmg Yield SB SB (%) ----(% control)---- (Bu/a) Rowel/Roundup Pmax RR2Y 2oz/32oz Warrant+Tric/RU+WUltra RR2Y 48+5oz/32+50oz Rowel/RU Xtend RR2X 2oz/64oz Row+Dic/RXtend+War RR2X 2oz+0.5lb/64+48oz Valor/Liberty LL 2oz/29oz Auth Maxx/Liberty+Zidua LL 64oz/29oz+2oz Lsd (5%) Planted and PRE 5/12, good PRE activation; Post 6/10, weeds < 2.

19 Weed control in Xtend soybeans, Manhattan, KS, 2016 (Peterson and Thompson). Herbicide Rate Girw Lacg Paam RU Pmax+Dicamba+Envive/ PMax+Dic RU Pmax+Dic+Envive/ Pmax+Dic+Cinch RU Pmax+Dic+Fierce/ Pmax+Dic RU Pmax+Dic+Fierce/ Pmax+Dic+Warrant 22oz+0.5lb+2.5oz/ 22oz+0.5lb 22oz+0.5lb+2oz/ 22oz+0.5lb+1pt 22oz+0.5lb+3.5 oz/ 22oz+0.5lb 22oz+0.5lb+3.5 oz/ 22oz+0.5lb+1 pt (% control) Lsd (5%) NS 3 NS PP treatments applied 5/3 To 8 giant ragweed; Xtend soybeans planted 5/23; Post treatments applied 6/13 to large crabgrass and Palmer amaranth < 4.

20 RR2 Xtend Soybeans Envive+Glyphosate+Dicamba (PP) fb Glyphosate+Dicamba (P)

21 RR2 Xtend Double Crop Soybeans Roundup Xtend+Auth MTZ (PP) fb Roundup Xtend +Warrant (P)

22 Xtendimax and Engenia Label Guidelines for Xtend Crops Weather restrictions Buffer zones Application requirements Approved spray tips Spray pressure limits No aerial application New e-label website for latest label updates

23 Xtendimax and Engenia Label Guidelines for Xtend Crops Only apply with TTI nozzles at a maximum of 63 psi. Minimum 10 gpa Do not exceed 15 mph ground speed Do not exceed boom height 24 above canopy Do not apply during temperature inversion Spray only between 3 and 15 mph Do not spray if wind > 10mph in direction of sensitive areas DO NOT APPLY this product when the wind is blowing toward adjacent commercially grown dicamba sensitive crops, including but not limited to, commercially grown tomatoes and other fruiting vegetables (EPA crop group 8), cucurbits (EPA crop group 9), and grapes.

24 Xtendimax Label Guidelines PROTECTION OF SENSITIVE AREAS Maintain a 110 foot downwind buffer (when applying 22 fluid ounces of this product per acre) or a 220 foot downwind buffer (when applying 44 fluid ounces of this product per acre) between the last treated row and the closest downwind edge (in the direction in which the wind is blowing). If any of the following areas below are directly adjacent to the treated field, the areas listed below can be considered part of the buffer distance. To maintain this required buffer zone: No application swath can be initiated in, or into an area that is within the applicable buffer distance. The following areas may be included in the buffer distance calculation when adjacent to field edges: Roads, paved or gravel surfaces, Planted agricultural fields containing: corn, dicamba tolerant cotton, dicamba tolerant soybean, sorghum, proso millet, small grains and sugarcane. If the applicator intends to include such crops as dicamba tolerant cotton and/or dicamba tolerant soybeans in the buffer distance calculation, the applicator must confirm the crops are in fact dicamba tolerant and not conventional cotton and/or soybeans. Agricultural fields that have been prepared for planting. Areas covered by the footprint of a building, silo, or other man made structure with walls and or roof.

25 Enlist Soybeans Soybeans that contain a 2,4-D resistant gene that is also stacked with both glufosinate and glyphosate resistant traits. 2,4-D resistance is based on metabolism of 2,4-D by soybeans Enlist trait deregulated by USDA and Enlist Duo approved by EPA in fall of 2014 Export approvals for China and EU pending

26 Enlist Soybeans 2,4-D Product New 2,4-D choline formulation that has less volatility losses than 2,4-D amine. 2,4-D choline is the only 2,4-D formulation labeled for use on Enlist soybeans. Enlist Duo is a premix of glyphosate and 2,4-D choline and will be the only 2,4-D choline product available initially. Standard rate of 3.5 pt/a. is equal to 0.75 lb ae glyphosate lb ae 2,4-D (~ 1.5 pt of 4lb 2,4-D).

27 Enlist Duo on Enlist Soybeans Rate: 3.5 to 4.75 pt/ac Timing: Preplant or preemergence Postemergence from Emergence to R2 soybeans Weeds less than 6 inches tall Do not apply more than 1 PP or PRE treatment and no more than 2 Postemergence treatments. Recommended as part of sequential program with residual PRE herbicide program Do not apply aerially

28 Enlist Duo Stewardship Guidelines Weather restrictions Buffer zones Application requirements Approved spray tips Spray pressure limits Enlist Ahead Website: Enlist Ahead App for treatment decisions

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30 Protection of sensitive areas or state restrictions which ever is most restrictive

31 You must maintain a 30 foot downwind buffer (in the direction in which the wind is blowing) from any area except: 1. Roads, paved or gravel surfaces. 2. Planted agricultural fields. (Except those crops listed in the Susceptible Plants section) 3. Agricultural fields that that have been prepared for planting. 4. Areas covered by the footprint of a building, shade house, green house, silo, feed crib, or other man made structure with walls and or roof. At the time of application, the wind cannot be blowing toward adjacent commercially grown tomatoes and other fruiting vegetables (EPA crop group 8), cucurbits (EPA crop group 9), grapes and cotton without the Enlist trait.

32 2,4-D and Dicamba Resistant Soybeans Potential Benefits Improved control of hard to control weeds Morningglory, velvetleaf, kochia, buckwheat, smartweeds, etc Improved control of herbicide resistant weeds Marestail, pigweeds, ragweeds, kochia Excellent crop tolerance on resistant varieties Expanded rate options Improved flexibility of burndown options without preplant interval restrictions

33 2,4-D and Dicamba Resistant Soybeans Potential Risks Perception that herbicide resistant crops will solve all weed problems Discourage use of residual herbicides Over reliance on new technology and development of 2,4-D and/or dicamba resistant weeds Further development of weeds with multiple resistance to different herbicide MOA s

34 2,4-D and Dicamba Resistant Soybeans Potential Risks Spray drift to non-resistant varieties and crops Spray tank contamination on subsequent applications to non-resistant varieties and crops Misapplication to non-resistant fields Poor record keeping Miscommunication with applicator

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36 Xtend and Enlist Soybeans are not Cross Resistant Dicamba application to Enlist Soybeans 2,4-D application to Xtend Soybeans

37 Rinse Effect following Dicamba Single Rinse Double Rinse Triple Rinse

38 2,4-D and Dicamba Resistant Soybeans Summary New herbicide resistant crop technologies will provide new options to help with weed control, but need to be part of an integrated weed management program that utilizes residual herbicides and different herbicide modes of action to optimize weed control and crop production, while sustaining the technology. Stewardship will be critical to long-term success.

39 HPPD Soybeans Soybeans that contain a gene that conveys resistance to certain HPPD herbicides. Varieties will be phased in over time with different stacked traits. Balance GT Beans from Bayer Resistance to isoxaflutole (Balance Bean herbicide) and glyphosate. Balance GTLL Beans from Bayer Resistance to isoxaflutole, glyphosate, and glufosinate. MGI soybeans from Syngenta Resistance to mesotrione (Callisto), isoxaflutole (Balance), and glufosinate (Liberty). Likely stacked with glyphosate resistance. Metabolism based resistance. Commercialization 2017?

40 Balance 2 fl oz/a + Sencor 5.33 oz/a

41 Balance 3 fl oz/a + Dual II 1 pt/a Fby 29 oz/a

42 HPPD Resistant Soybeans Potential Benefits and Risks Improved control of herbicide resistant and other hard to control weed species in soybeans. New herbicide mode of action for soybeans. Multiple herbicide resistant traits and herbicide options. Increased selection pressure for HPPD resistant weeds.

43 Dallas Peterson Extension Weed Specialist Department of Agronomy

44 Dallas Peterson Professor and Extension Weed Specialist Department of Agronomy Kansas State University 2014 Throckmorton Hall Manhattan, KS Office: Cell: Biography Dallas Peterson is a Professor and Extension Weed Specialist at Kansas State University. He grew up on a small farm in north central Kansas and received his B.S. and M.S. degrees in Agronomy from Kansas State University and Ph.D. at North Dakota State University. Dallas worked as an Assistant Professor and Extension Weed Specialist in North Dakota before returning to Kansas State in 1989 in a similar capacity. He conducts applied weed management research on agronomic crops and provides educational programming and weed management information to Kansas farmers and crop advisors. Dallas recently served as President of the Weed Science Society of America.