Brash, or weedmaster weed killer, comes in a premix formula of amine plus dicamba with 2,4-D. A growth regulator, the substance controls broadleaf weeds. Brash should always be used with caution when applied to a cattle foraging pasture. The herbicide offers the best control of weeds when applied during the active growing phase of the pasture.

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Brash works an effective broadleaf weed control herbicide in cattle pastures.

Applicaton Rates and Hay Harvest

Always wait at least 37 days after applying Brash to a hay field before harvesting for livestock consumption. Control annual weeds by applying 1 pint of Brash per acre during the weeds active growth phase. Biennial weeds will require 1 to 2 quarts per acre for successful control. The herbicide can provide excellent control if the pasture biennial weed appears within the rosette growth stage. Apply 2 quarts of Brash per acre to control perennial weeds. The herbicide will give only limited success at controlling creeping perennial weeds.

Lactating Cows and Herbicide Application Precautions

Avoid allowing lactating cows to graze on any field sprayed with Brash for at least seven days. Lactating cows can eat hay harvested from a field treated with Brash if the harvest took place 37 days after the herbicide's application to the field. When applying the herbicide, make sure that it does not drift or blow onto neighboring trees, shrubs or fields. The herbicide can cause serious injury or death to broadleaf crops. Insure that no danger of groundwater contamination can occur when applying brash. The pesticide 2,4-D can pose a threat to groundwater if runoff should occur. Do not use Brash where it can come into contact with aquatic life. If accumulation or runoff should appear in streams or other water bodies, the aquatic life can die.

Application Considerations

When applying brash to a field, avoid applying it within four hours of any irrigation or rainfall. If applied within four hours, the herbicide may not produce maximum benefit at weed control. The field should not suffer stress when applying Brash; drought, flooding, cultivation injuries, varying outdoor temperatures and any type damage the fodder crops have sustained may all reduce the effectiveness of Brash. Always remove cattle from any field treated with Brash at least 30 days prior to slaughtering the animal, so no herbicide residue remains in the animal's flesh.

Warnings

Avoid feeding any sorghum forage or silage to livestock prior to the mature grain stage. Wait at least seven days after applying Brash before harvesting a wheat field. When renovating a field with new seeds wait at least three weeks after using Brash before seeding so damage does not happen to the newly seeded field. Avoid using more than 2 pints of Brash per acre in a newly seeded pasture. Brash offers reduced control potential if the weeds exceed 1 inch in height at the time of application. Do not use Brash on alfalfa, bentgrass, buffalograss, St. Augustine grass, clover, vetch, wild winter peas or lespedeza or damage will occur to the pasture.