Supporters of legalized hemp are counting heavily on Mitch McConnell | McClatchy Washington Bureau

The future of hemp legalization is up to Mitch McConnell. Period.

House supporters of the idea tried to include legalization measures into the big farm bill lawmakers have been considering, but were advised to back off

McConnell’s taking care of things, they were told.

Reps. Andy Barr, R-Kentucky, and James Comer, R-Kentucky, and others tried to get the House to vote on a plan.

Forget it, said Rules Committee chairman Rep. Pete Sessions, R-Texas. The committee, controlled by House leaders, largely decides what the House will consider.

Sessions made it clear this issue is all McConnell’s.

“A decision on this effort, including the language, has been determined by an agreement that would be reached with Mr. McConnell,” Sessions told Rep. Jared Polis, D-Colorado, who asked for a vote on a proposal by him and Comer to take hemp off the list of controlled substances. Their effort failed 8 to 3.

McConnell, the Senate Majority Leader, has long been an advocate for legalized hemp, an important crop in his home state. The six-term senator is expected to seek another term in 2020, and has already begun putting an organization together. Support from the state’s rural sector will be crucial.

McConnell is a member of the Senate Agriculture Committee and has won the Kentucky Farm Bureau’s “Golden Plow” award.

Hemp was once a leading cash crop in Kentucky. The federal government during World War II had the state’s farmers grow hemp for the war effort, though it was banned elsewhere.

Nowadays, Comer, a former Kentucky agriculture commissioner, said Kentucky's hemp pilot program has been a "great success."

He said it had evolved from 20 growers and 33 acres in 2014 to 201 growers and 14,000 acres approved this year.

Comer told the Rules Committee that farmers "want confidence that this is a legitimate crop and this amendment would do that."

But hemp has found roadblocks. Critics have been worried that legal hemp could provide momentum to marijuana supporters, who want to scrap the federal ban against pot. Both are classified as controlled substances, banned by Congress for decades.

Hemp is the non-intoxicating sister plant of marijuana. Both come from the same species, Cannabis sativa, but hemp has only a trace of THC, the chemical that produces a high.

Hemp has several uses, its supporters say, from clothing to construction materials. Kentucky automakers want to copy their German counterparts and use hemp fiber in car dashboards and door panels.

Senate Agriculture Committee Chairman Pat Roberts, R-Kansas, said he's talked to McConnell about including the hemp provision, which Roberts said could benefit farming states beyond Kentucky.

"This is the newest crop we have and there's an awful lot of things that research has proved we can do with hemp," Roberts said.

A spokesman for McConnell, who successfully tucked a provision into the 2014 farm bill to allow states to make limited hemp cultivation legal, said the senator has had numerous conversations about including hemp legislation in the 2018 farm policy bill.

“We look forward to continuing those conversations … as we continue to move toward delivering a final bill to the president,” said Robert Steurer, a McConnell spokesman.

Barr and Comer, who introduced hemp-related amendments to the House farm bill, said they had assurances from Sessions that the final farm bill — one where compromise is negotiated between the House and Senate versions — would include McConnell’s initiative.

That would remove hemp from the federal list of controlled substances, giving farmers across the country the ability to grow it legally.

“We believe that this approach will give us the best chance for a successful outcome,” Barr said.

The House version of the farm bill collapsed Friday when conservative lawmakers voted against it over frustrations with unrelated immigration legislation. It’s unclear when the House will return to the legislation, which faces opposition in the Senate because of the changes to the Supplemental Nutrition Assistance Program.

The Senate is expected to consider its own bill later this year. Should it pass, and a version of the House measures passes, negotiators would craft a single measure — a bill that thanks to McConnell would almost certainly include a provision on hemp.