Wiregrass, African or ventenata (Ventenata dubia)

imazapic (Plateau, Panoramic)

Rate 5 oz /a Plateau or Panoramic

Time Apply in the fall after African wiregrass has emerged.

Remarks High litter levels may reduce effectiveness, some bare ground should be visible for better control. Labeled for use on pasture, range, Conservation Reserve Program (CRP), and non-cropland.

Caution Many perennial grasses can be injured if applications are made during the spring.

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

Chemical family Imidazolinone

sulfosulfuron (Outrider)

Rate 0.75 oz/a Outrider

Time Apply in the fall after African wiregrass has emerged (1 inch rain and soil temperature above 45°F).

Remarks Many grasses are sensitive to sulfosulfuron so selection of grasses for any revegetation efforts should consider use of wheatgrasses. Mature Idaho fescue is tolerant and while perennial bromes are injured during the first season, they will persist. Meadow foxtail (Alopecurus pratensis) is removed from perennial grass stands so if this species is used for forage, avoid applying sulfosulfuron.

Caution Labeled for use on pasture, range, Conservation Reserve Program (CRP), and non-cropland. Wheat is the only rotational crop for one year after application, see label for details.

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

Chemical family Sulfonylurea

flufenacet + metribuzin (Axiom DF)

Rate 0.27 to 0.31 lb ai/a flufenacet + 0.068 to 0.084 lb ai/a metribuzin (8 to 10 oz/a Axiom) in established timothy hay.

Time Apply before weeds emerge, or no later than the two-leaf stage.

Remarks Do not graze timothy in the fall and cut height cannot be shorter than 3.5 inches. Rain or irrigation after application is needed for sufficient weed control activity.

Caution Harvest at lower than 3.5 inches may cause injury to timothy. Grazing in fall after hay harvest may cause injury to timothy. It is best to harvest at 4 inches to allow energy stored in stems to be used to produce new stems next year.

Site of action (flufenacet) Group 15: inhibits very long chain fatty acid synthesis; (metribuzin) Group 5: photosystem II inhibitor

Chemical family (flufenacet) oxyacetamide; (metribuzin) triazinone

indaziflam (Esplanade 200 SC)

Rate 3.5 to 7 oz/a

Time Apply preemergence.

Remarks Controls many other annual grasses and some broadleaf weeds.

Caution Keep away from surface water, at least 25 feet, and areas below the mean watermark.

Site of action Group 29: cellulose biosynthesis inhibitor

Chemical family Alkylazine

rimsulfuron (Matrix, Laramie)

Rate 2 to 4 oz /a

Time Apply before or soon after seedlings emerge.

Remarks Controls some other annual grasses, and some annual broadleaf species. Add a nonionic surfactant at 1 quart/100 gal spray to improve activity.

Caution Consult label if there are plans to seed grasses after application.

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

Chemical family Sulfonylurea