Command / clomazone

WSSA Resistance Group: 13

Crop/non-crop registration: Soybean, peppers, pumpkins, peas

Sensitive weeds: Annual grasses and BLW (broadleaf weeds): barnyard grass, Panicum spp., crabgrasses, velvetleaf, common ragweed, lambsquarters.

Application method: PPI or PRE.

Absorption & Translocation: Not highly absorbed when foliar applied;readily absorbed by roots and emerging shoots (grass coleoptile and broadleaf hypocotyl) and is translocated to foliage via xylem.

Mode of Action: Not completely understood; but thought to inhibit the isoprenoid pathway.

Metabolic pathway inhibited: Inhibition of the isoprenoid pathway stops production of among other things gibberellin, plastoquinone, carotenoids, and the phytol tail of chlorophyll.

Basis of Selectivity: Metabolized to non-toxic compounds by tolerant species.

Symptoms: Susceptible seedlings typically emerge from treated soil, but are bleached white and become necrotic after a few days.

Residuality: Intermediate (1- 4 months); decreasing persistence in sandy loam soils compared with silt loam or clay loam soils.

Toxicity: Oral LD50 = 2077 mg/kg - moderately toxic (COMMAND = 2343 mg/kg - moderately toxic).

Additional comments: Susceptible species in later growth stages may exhibit foliar bleaching when treated POST or when exposed to vapor drifting from nearby treated areas.

Images above: Clomazone (PRE) on wild mustard (left). Clomazone (PRE) on tomatoes (right).

Images above: Clomazone (PRE) on redroot pigweed (left). Clomazone (PRE) on grass weeds including barnyardgrass, yellow foxtail and large crabgrass (right).

Images above: Clomazone (PRE) on various crops including corn, soybean, alfalfa and winter wheat (left). Clomazone (PRE) on corn (right).