1. Issues in Weed Management, 2004 Fabián Menalled Cropland Weed Specialist 719 Leon Johnson Hall Montana State University menalled@montana.edu 406-994-4783

2. Weed Science at MSU Herbicide Resistance Herbicide Update Issues in Weed Management, 2004

3. Cropland Weed Management Web Site http://scarab.msu.montana.edu/cropweeds/index.htm Google: Cropland + weed + Montana

10. Weed Management Handbook Available: December 2004 On-line Extension Publications Montana State University P.O. Box 172040 Bozeman, MT 59717-2040 406-994-3273

11. Weed Science at MSU  Herbicide Resistance Herbicide Update Issues in Weed Management, 2004

12. Herbicide Resistance Innate ability of a species to survive and reproduce after treatment with a dose of herbicide that would normally be lethal

14. WeedSituationHerbicide Mode of Action Kochiarailways Photosystem II inhibitors (atrazine) wheat ALS inhibitors (chlorsulfuron, metsulfuron-methyl) wheat Synthetic Auxins (dicamba, fluroxypyr) Wild oatbarley Thiocarbamates and others (difenzoquat, triallate) barley Pyrazoliums (difenzoquat, triallate) sugarbeet, wheat ACCase inhibitors (diclofop-methyl, fenoxaprop-p-ethyl, tralkoxydim) cereals ALS inhibitors (imazamethabenz-methyl) Russian Thistlewheat ALS inhibitors (chlorsulfuron) Persian Darnellwheat ACCase inhibitors (diclofop-methyl)

15. Herbicide Resistance Idaho –Prickly lettuce –Kochia –Russian thistle –Wild Oat –Italian ryegrass –Mayweed chamomile Wyoming –Kochia –Italian ryegrass North Dakota –Kochia –Green foxtail –Wild oat –Redroot pigweed –Wild mustard –E. black nightshade Utah –Kochia

17. Herbicide Resistance Selection intensity –Herbicide efficacy –Number of herbicide applications / year Weed biology –Genetic variability –Reproduction mechanism Genetics of resistance –ALS or ACCase vs. EPSP synthase

18. Resistance Management ROTATE!!!!! –Management practices –Crops SITE OF ACTION –Herbicides with different SITE OF ACTION

19. Herbicide Mode of Action Sequence of events from absorption of the herbicide into the plant until the plant dies

20. Contact Absorption Toxicity Movement Herbicide Mode of Action

21. Commercial Products ( Roundup, Ultramax, etc. ) Mode of Action (Amino Acid Biosyntehsis Inhibitors) Site of Action ( EPSPS inhibitor ) Chemical Family ( Glyicines ) Active Ingredient ( Glyphosate )

22. Herbicide Mode of Action HMOAExample Growth regulators2-4,D; Banvel; Starane Amino acid synthesis inhibitors ALS inhibitors: Glean; Harmony Extra; Everest EPSP inhibitors: Roundup Lipid inhibitorsACC-ase inhibitors: Select; Puma; Hoelon Seedling growth inhibitorsFar-go Photosynthesis inhibitorsTriazines: Bladex Nitriles: Buctril Cell membrane disruptorsDiquat; Gramoxone Pigment inhibitorsCommand

23. Weed Management in Montana Based on few HMOA –Amino acids biosynthesis inhibitors (Roundup and the Sulfonylureas) –Growth regulators (2,4-D, MCPA) –ACCase inhibitors (Holeon and Achieve )

24. Weed Science at MSU Herbicide Resistance  Herbicide Update Issues in Weed Management, 2004

25. Herbicide Update Familiar Faces, New Names

26. WideMatch, Dow AgroSciences Osprey, Bayer Silverado, Bayer Olympus, Bayer Durango & Glyphomax XRT, Dow AgroSciences Velpar Alfamax, DuPont

27. WideMatch Clopyralid/MCPA ester + fluroxypyr WideMatch Clopyralid/MCPA ester + fluroxypyr Curtail + Starane Growth regulators Wheat, durum, oat, barley Broadleaf control: Canada thistle, wild buckwheat, ALS-resistant and large kochia. Tank-mixed: Achieve, Discover, Everest, Puma Three-leaf stage to flag leaf emergence Rate: 1.0 to 1.3 pt / A Rotation: 18 months for pea, lentil, and potato Cost: approximately $7.50 to $8.00/A

28. ALS-inhibiting herbicide Winter wheat Wild oats, Persian Darnel, ryegrass and certain broadleaf weeds Control ACC-ase resistant grasses (wild oat) Emergence to jointing stage Rate: 4.45 oz / A + adjuvant Flathead and Lake Co. Restrictions! Tank-mixed: Curtail, Harmony, Bronate Advance, etc. Rotation: 7 days for wheat; 90 days for lentils, peas and dry beans; 12 months for corn Osprey Mesosulfuron-methyl

29. Silverado Mesosulfuron-methyl ALS-inhibiting herbicide winter and spring wheat, including durum Wild oat control in Eastern Montana ACC-ase-resistant wild oats Emergence to jointing stage 1.75 -2.25 ounces / A + adjuvant Tank-mixed: MCPA ester, Harmony Extra, Curtail, etc Rotation: 7 days for wheat and barley; 90 days for lentils, peas and dry beans; 12 months for corn Cost: $8.75/A + the adjuvant

30. ALS-inhibiting herbicide spring, durum and winter wheat Cheat grass, downy brome, Japanese brome. Suppression of jointed goatgrass Control ACC-ase resistant grasses (wild oat) Emergence to jointing 0.6 to 0.9 oz./acre in a single application Tank-mixed: Amber, MCPA, Starane, 2,4-D, etc. Rotation: 4 months for Proso Millet, 22 months for corn Cost: Approximately $ 9.00 / Acre Olympus Propoxycarbazone-sodium

31. EPSP inhibitors Glyphosate stewardship guidelines Durango & Glyphomax XRT Glyphosate

32. Velpar – Alfamax Velpar – Alfamax Diuron and Velpar (hexazinone) Established alfalfa Contact and residual control One single application during winter Rates = 3.3 – 10 Acres / Unit Pack (14.2 pounds), Mustards, pigweed, chickweed, common lambsquarters Branyardgrass, cheatgrass Dry bulk fertilizer may be coated with Velpar - Alfamax Caution: can damage trees and shrubs

33. Section 24(c). Special Local Needs Velpar LAlfalfa, dormant forage General weed control Roundup (Original and Ultra Max RT) Peas (Dry), Lentils, Chickpeas General weed control BasagranSeed AlfalfaCanada thistle, mayweed & other weeds ProwlSeed AlfalfaGeneral weed control Sonalan HFPSeed AlfalfaNightshade and Dodder Fusilade DXSeed AlfalfaQuackgrass SencorSeed GrassesBromus Species

34. ALWAYS READ THE LABEL!!!!!!!!