LITTLE ROCK (AP) — Arkansas lawmakers have endorsed a proposal to allow limited use of an herbicide that was banned following complaints that it drifted onto nearby crops and caused widespread damage.
A subcommittee of the Joint Budget Committee on Monday approved the state Plant Board's proposed rules regarding the use of the herbicide dicamba. The Plant Board last week voted to allow dicamba's use through May 25.
The rules now head to the full Joint Budget Committee.
The new restrictions also would impose a half-mile buffer zone around research stations, organic crops, specialty crops, non-tolerant dicamba crops and other sensitive crops. The state had previously banned dicamba's use from April 16 through Oct. 31. Arkansas enacted the ban last year after receiving nearly 1,000 complaints about damage from dicamba.
Dicamba kills annual and perennial broadleaf weeds. Its primary commercial applications are weed control for grain crops and turf areas. It is also used to control brush and bracken in pastures, as well as controlling legumes and cacti. In combination with a phenoxy herbicide or with other herbicides, dicamba can be used for weed control in range land and other noncrop areas (fence rows, roadways, and wastage).
Dicamba is toxic to conifer species but is in general less toxic to grasses.
Dicamba functions by increasing plant growth rate. At sufficient concentrations, the plant outgrows its nutrient supplies and dies.
The growth regulating properties of dicamba were first discovered by Zimmerman and Hitchcock in 1942. Soon after Jealott's Hill Experimental Station in England was evaluating dicamba in the field. Dicamba has since been used for household and commercial weed control.
Increasing use of dicamba has been reported with the release of dicamba-resistant genetically modified plants by Monsanto. In October 2016, the EPA launched a criminal investigation into the illegal application of older, drift prone formulations of dicamba onto these new plants. Older formulations have been reported to drift after application and affect other crops not meant to be treated.
A less volatile formulation of dicamba made by Monsanto, designed to be less prone to vaporizing and inhibit unintended drift between fields, was approved for use in the United States by the EPA in 2016, and was expected to be commercially available in 2017.