Annual Grasses and Broadleaf Weeds in Established Stands

flumioxazin (Chateau)

Rate 0.6375 lb ai/a (4 oz/a Chateau)

Time Apply preemergence to the weeds.

Remarks Applications should be made as soon as possible after cutting and removing alfalfa to minimize crop injury. Flumioxazin will burn treated leaves and stems. A second application can be made 60 days after the first application. Gives only fair control of many annual grasses. Apply with paraquat to burn down weeds when applying after the last harvest in the fall or when alfalfa is dormant.

Caution Do not apply harvest or graze within 25 days of application. Do not make second application within 60 days of the first application. Do not exceed 8 oz of Chateau during a single growing season.

Site of action Group 14: protoporphyrinogen oxidase (PPO) inhibitor

Chemical family N-phenylphthalimide

imazamox (Raptor)

Rate 0.031 to 0.047 lb ai/a (4 to 6 oz/a Raptor)

Time Apply postemergence to actively growing weeds before they are 3 inches tall or across, and the alfalfa has less than 3 inches of regrowth.

Remarks May be applied to established alfalfa in the fall or winter, or in the spring to dormant or semi-dormant alfalfa, or between cuttings. Adding an adjuvant (nonionic surfactant or crop oil concentrate) and a liquid fertilizer or ammonium sulfate solution is required. Weeds under stress are less susceptible to control. Apply at least 1 hour before rain or overhead irrigation.

Caution Do not exceed 6 oz product/a per season. Note recropping restrictions before using. Some crops cannot be planted within 26 months of application. Only rotational crops harvested at maturity may be used for feed or forage.

Site of action Group 2: acetolactate synthase (ALS) inhibitor

Chemical family Imidazolinone

imazethapyr (Pursuit)

Rate 0.047 to 0.094 lb ai/a (3 to 6 oz/a Pursuit)

Time Apply to established alfalfa in the fall, in the spring to dormant or semidormant alfalfa (less than 3 inches of regrowth), or between cuttings, and when most weeds are actively growing and 1 to 3 inches tall or across.

Remarks Adding an adjuvant (nonionic surfactant or crop oil concentrate) and a liquid fertilizer solution is required. Temporary height reduction or slight leaf yellowing may occur soon after application. Weeds under stress are less susceptible to control. Apply at least 1 hour before rain or overhead irrigation.

Caution Do not feed, graze, or harvest alfalfa for 30 days after applying. Note recropping restrictions before use. Some rotation crops cannot be planted within 40 months of application. Only rotation crops harvested at maturity may be used for feed or food.

Site of action Group 2: acetolactate synthase (ALS) inhibitor

Chemical family Imidazolinone