Senator Ron Wyden (D-Oregon) on Thursday introduced an amendment to the farm bill that would allow farmers to grow industrial hemp.

The amendment, S.3240, would exclude industrial hemp from the definition of "marihuana," thereby allowing hemp farming to be regulated by state permitting programs, bypassing the federal government's long-standing prohibition of marijuana. A sister bill, H.R. 1831, was introduced in the House earlier this session by Rep. Ron Paul (R-Texas).

"The federal prohibition on growing industrial hemp has forced companies to needlessly import raw materials from other countries," said Wyden in a statement on Thursday. "My amendment to the Farm Bill will change federal policy to allow U.S. farmers to produce hemp for these safe and legitimate products right here, helping both producers and suppliers to grow and improve Oregon's economy in the process."

Seventeen states have passed pro-hemp legislation, while eight have removed barriers to its production. Still, farmers in these states are at risk of being raided by federal agents and losing their crops.

Vote Hemp, a national nonprofit dedicated to promoting the crop, is encouraging people to write and call their senators in support of the amendment and has received hundreds of supporter emails, according to National Outreach Coordinator Tom Murphy.

The organization's president, Eric Steenstra, said he thinks current hemp prohibitions stem largely from the failure of federal policy to distinguish between oilseed and fiber varieties of cannabis.

"Senator Wyden's effort is unprecedented and totally commendable, but in my view the existing prohibition of hemp farming stems less from current law, but rather the misinterpretation of existing law by the Obama administration," he said.