Arkansas regulators have voted to expand limited use of a new formulation of dicamba despite complaints that it drifted onto neighboring fields and destroyed crops.

A subcommittee of the state's Joint Budget Committee approved a proposal to allow use of the herbicide through May 25, by a vote of 9 to 6.

The proposal also requires a half-mile buffer around soybean and cotton fields for crops not specially engineered to withstand dicamba, and a mile buffer around research, specialty and organically grown crops.

Last year, the state had approved a ban of dicamba from April 16 to October 31 after hundreds of complaints from farmers when a recently reformulated version of the herbicide drifted onto nearby fields and damaged crops.

Producers of dicamba, Monsanto and BASF, have rejected research demonstrating the herbicide's harm to other crops, and claim that measures like improved applicators and training have solved issues with drift.

Studies at state universities in Nebraska, Indiana, Missouri, Arkansas, and Tennessee have shown that the new dicamba formula stays volatile and harmful to crops for at least four days after application.

Last year a farmer in Mississippi was convicted in the murder of another farmer in a dispute over dicamba drift.

Allan Curtis Jones was sentenced to 24 years in prison for shooting Mike Wallace during a physical confrontation.

Jones previously told The Wall Street Journal that at least 40 percent of his soybean crop had been damaged by dicamba drift.

Jones, who said in court that the shooting had been in self-defense, stated he will appeal the verdict.

Read More:

• Arkansas Lawmakers Back Limited Use Of Herbicide Dicamba (Associated Press)
• Arkansas Approves Expanded Dicamba Use, Dismissing Scientific And Public Concerns (Fern's Ag Insider)

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