Site Maintenance-Postemergent Grass Control

clethodim (Arrow and others)

For control and/or suppression of tall fescue in native prairie warm-season grass restoration projects

Rate 0.156 to 0.1875 lb ai/a (10 to 12 fl oz/a) depending on growth stage of grass.

Time Usually before weeds are 4 to 6 inches tall, but depends on grass species present. Apply to actively growing grasses that are not stressed by drought.

Remarks Annual and perennial grass control. Always add crop oil concentrate at 1% v/v and spray grade ammonium sulfate at 2.5 to 4 lbs./a.

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

Chemical family Cyclohexanedione

fluazifop (Fusilade DX)

Oregon only. For control of grassy weeds in prairie, riparian, and habitat restoration projects

Rate 0.375 lb ai/a (24 oz/a) Maximum use rate is 72 oz/a per year.

Time Apply spring or fall to actively growing grasses 2 to 4 inches tall.

Remarks Apply with 1% v/v crop oil concentrate or 0.25% v/v nonionic surfactant. Repeat application may be needed to control perennial weeds such as quackgrass. Cultivate perennial weeds to break up roots to produce more shoots before spray. Do not cultivated within 7 days of application. Acts very slowly, taking at least 2 and often 4 weeks to show effects. Do not apply to stressed grasses. Apply with 20 to 40 gal/a water; thorough spray coverage is important. SLN OR-120016

Caution Do not graze treated fields. Do not tank mix with triclopyr or aminopyralid containing products as reduced grass control may occur.

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

Chemical family Aryloxyphenoxy propionate

sethoxydim (Poast)

Natural areas including wildlife management areas and wildlife openings and wildlife habitats

Rate Maximum single application is 0.47 lb ai/a (2.5 pints/a); maximum annual rate is 7.5 pints/a

Time Apply to actively growing grasses.

Remarks Apply with 2 pints/a crop oil concentrate. Sethoxydim acts very slowly, taking at least 2 weeks and often 4 weeks to show herbicide effectiveness. Do not apply to stressed grasses. Grasses such as fescue are tolerant.

Caution Do not apply if rain is expected within 1 hour. Do not graze.

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

Chemical family Cyclohexanedione