Quackgrass, Volunteer Grains, and Annual Grasses in New or Established Stands

clethodim (Select 2EC, Select Max, Intensity, or Intensity One)

Rate Select 2EC, or Intensity: use 0.094 to 0.25 lb ai/a (6 to 16 fl oz/a product). Select Max or Intensity One: use 0.07 to 0.24 lb ai/a (9 to 32 fl oz/a product).

Time Apply to actively growing annual or perennial grasses in the labeled growth stage.

Remarks Controls grass only, but is weak on quackgrass. Refer to label for specific weed species and weed size. Always add a crop oil concentrate containing at least 15% emulsifier, at 1% v/v, in the finished spray volume. Adding ammonium sulfate improves control of difficult-to-control grasses. Most effective on actively growing grasses before they reach the maximum size listed on label. For best results in irrigated alfalfa, apply within 2 to 4 days after irrigation. Use higher rate under heavy grass pressure and/or when annual bluegrass is more mature.

Caution Control may be erratic on grasses stressed by drought, temperature extremes, insect damage, herbicide injury, or other factors, or if grasses are larger than indicated on label. Do not apply if rain is expected within 1 hour after application. Do not apply within 15 days of grazing, feeding, or harvesting for forage or hay. Do not exceed 0.5 lb ai/a per season (32 fl oz/a of Select 2EC or 64 fl oz/a of Select Max).

Site of action Group 1: acetyl CoA carboxylase (ACCase) inhibitor

Chemical family Cyclohexanedione

fluazifop (Fusilade DX)

Rate 0.125 to 0.188 lb ai/a (0.5 to 0.75 pints/a Fusilade DX)

Time Apply to actively growing, susceptible grasses in the labeled growth stage.

Remarks Special local needs labels OR-040006, ID-950006, and WA-040007. Add a crop oil concentrate at 0.5% to 1% concentration or a nonionic surfactant at 0.25% to 0.5% concentration. Results often are erratic on grasses stressed from lack of vigor, drought, high temperatures, low fertility, or other factors. More mature grasses and quackgrass can be controlled but may require two applications. Will not control annual bluegrass or any of the fine fescues. Fluazifop is often weak on foxtails and perennial bluegrass.

Caution Do not feed treated forage to livestock.

Site of action Group 1: acetyl CoA carboxylase (ACCase) inhibitor

Chemical family Aryloxyphenoxypropionate

pronamide (Kerb 50-W, Kerb SC)

Rate 0.5 to 2 lb ai/a (1 to 4 lb/a 50-W; 1.2 to 4.8 pints/a SC)

Time Apply October through early December.

Remarks Results are best if applied under cool conditions (55°F or cooler) and followed by rain or overhead irrigation. Use the higher rates for perennial grass control. On fields to be treated, remove residue by burning or tilling into the soil.

Caution A restricted-use herbicide. Apply on new plantings only after alfalfa has reached the first trifoliate-leaf stage of growth. Do not apply preplant, preemergence, or in the seed-leaf stage. Do not graze treated fields or feed clippings and crop residues to livestock within 25 days of application (if less than 1.5 lb ai/a) or within 45 days (if 1.5 to 2 lb ai/a). Do not apply on frozen ground. Must be applied by certified applicators, or people directly under a certified applicator's direction. Kerb SC is registered for OR, WA, and ID under Special local needs labels.

Site of action Group 3: microtubule assembly inhibitor

Chemical family Benzamide

quizalofop (Assure II)

Rate 0.034 to 0.0825 lb ai/a (5 to 12 oz/a Assure II)

Time Apply to actively growing annual or perennial grasses in the labeled growth stage.

Remarks See label for specific herbicide rates, weed species, and weed size. Under arid conditions, use higher rate for the target grass weed. Always include a nonphytotoxic crop oil concentrate at 1% v/v or a nonionic surfactant at 0.25% v/v. Crop oil concentrate is preferred in arid areas. Will not control annual bluegrass or fine fescue. Control may be reduced on grasses stressed from lack of moisture, cold, herbicide injury, or insect injury or disease.

Caution Do not apply within 14 days of anticipated bloom. Do not use any part of crop (seed, sprouts, screenings, hay, forage, etc.) for animal or human consumption. Do not exceed two applications or 0.17 lb ai/a (25 oz/a product) per season.

Site of action Group 1: acetyl CoA carboxylase (ACCase) inhibitor

Chemical family Aryloxyphenoxypropionate

sethoxydim (Poast or Poast Plus)

Rate 0.19 to 0.47 lb ai/a (1 to 2.5 pints/a Poast)

Time Apply to actively growing annual or perennial grasses in the labeled growth stage.

Remarks See label for specific herbicide rates, weed species, and weed size. Always add a nonphytotoxic oil concentrate to spray tank at 2 pints/a. Most effective on actively growing grasses before they are cut or reach the maximum size indicated on label. Larger, more mature grasses can be controlled, but two applications may be required. Will not control annual bluegrass or any of the fine fescues.

Caution Control often is erratic on grasses stressed by drought, temperature extremes, insect damage, herbicide injury, or other factors. Do not apply if rain is expected within 1 hour after application. Do not exceed 1.22 lb ai/a in one season.

Site of action Group 1: acetyl CoA carboxylase (ACCase) inhibitor

Chemical family Cyclohexanedione