2,4-D LV ester
Rate 1 to 2 lb ae/A
Time Apply in early spring when plants are actively growing before bloom stage.
Remarks Halogeton is poisonous to livestock. Chemical control is effective but will be futile unless desirable plants occupy the site immediately.
Caution Following application, do not graze until after plants dry up.
Site of action Group 4: synthetic auxin
Chemical family Phenoxy acetic acid
aminocyclopyrachlor + chlorsulfuron (Perspective)
Rate 1.2 to 1.8 oz/A aminocyclopyrachlor + 0.5 to 0.7 oz/A chlorsulfuron (3 to 4.5 oz/A of product)
Time Apply to actively growing vegetation.
Remarks Adjuvants can be used; these include methylated seed oils 0.5 to 1% v/v, nonionic surfactants at 0.25 to 1% v/v, and crop oil concentrates at 1% v/v. Can be applied using an invert emulsion rather than water.
Caution Even low rates can kill nontarget tree and shrub species, so avoid application within a distance equal to the tree height of the sensitive species. Do not allow spray to drift off target. Can injure several grass species including bromes, as well as basin wildrye.
Site of action (aminocyclopyrachlor) Group 4 synthetic auxin (chlorsulfuron) Group 2: ALS inhibitor
Chemical family (aminocyclopyrachlor) Pyrimidine carboxylic acid; (chlorsulfuron) Sulfonylurea
imazapic (Plateau)
Rate 0.063 to 0.188 lb/A
Time Apply preemergence or early postemergence.
Remarks For postemergence timing, use at least 0.094 lb/A plus a surfactant. Selective to most native grasses. Higher rates may suppress seed of some cool-season grasses.
Caution Before using, note crop rotation restrictions.
Site of action Group 2: acetolactate synthase (ALS) inhibitor
Chemical family Imidazolinone
metsulfuron (Escort and others)
Rate Escort: 0.45 oz ai/A (0.75 oz/A)
Time Apply to actively growing halogeton.
Remarks Use a surfactant. Application sites differ among products at the above rate; consult labels.
Caution Do not let spray drift onto sensitive crops. Apply only to pasture, rangeland, and non-crop sites.
Site of action Group 2: acetolactate synthase (ALS) inhibitor
Chemical family Sulfonylurea