Gov. Asa Hutchinson has approved proposed regulations by the Arkansas Plant Board to limit use of herbicides containing dicamba. Hutchinson said Wednesday that he’s determined the proposal will not cause unnecessary burdens on businesses but said the methods and research used by the board must be clearly defined and he wants the board to provide “clear rules” within 45 days. Dicamba is a relatively inexpensive weed killer but is prone to drift and damage nearby row crops such as soybeans and cotton in addition to fruit and vegetable farms and ornamental trees. The proposals include banning dicamba known as DMA except on pastures at least 1 mile from susceptible crops and prohibiting dicamba known as DGS from April 15-Sept. 15, except on pasture and rangeland with a 1-mile buffer zone.