Imagine a crop that can be used to purify soil and make food, clothing, rope, paper, plastic, pest-resistant building material, oil, fuel, animal bedding and tens of thousands of other products. The Declaration of Independence was written on it; George Washington and Thomas Jefferson grew it; Betsy Ross made the American flag out of it; and Henry Ford built and ran cars with it.

But it’s been illegal to grow in the United States for more than 50 years.

"I’ve worked to legalize industrial hemp for Hawaii as a mainstream agricultural crop for 20 years," state Rep. Cynthia Thielen, a champion for hemp legalization, said during an interview in her office Thursday. "When the sugar plantations began to shut down, I looked at hemp as a natural replacement for the sugar crop. … It’s one of the most valuable crops for farmers, and there are 25,000 uses for the plant — none of which will get you high."

Although hemp is identified as part of the cannabis sativa plant species along with marijuana, it doesn’t contain anywhere near the level of tetrahydrocannabinol (THC) needed to get a user high.

Thielen (R, Kailua-Kaneohe) and other industrial hemp supporters caught a break in February when President Barack Obama signed an agriculture bill with language that authorizes state universities and agriculture departments to engage in industrial hemp research projects without obtaining Drug Enforcement Administration permits that were previously required.

IN LIGHT of that law, state legislators worked this session to craft a bill asking the University of Hawaii’s College of Tropical Agriculture and Human Resources to start an industrial hemp research project, and the measure recently went to Gov. Neil Abercrombie for final approval.

During World War II, the U.S. government produced an informational film in the 1940s titled "Hemp for Victory" to encourage farmers to grow the crop to help with war efforts, such as making ropes and parachute cords.

But there hasn’t been a commercial crop planted since 1957, when the DEA began interpreting the Controlled Substances Act as preventing industrial hemp growth.

The state in 1999 implemented a law similar to the proposed bill, but Thielen said the DEA "really yanked the rug out from under that project after three years."

Some lawmakers, including Thielen, are confident that growing hemp in Hawaii could make good use of vacant or contaminated agriculture land and kick-start a new industry in the isles.

Sen. Will Espero, chairman of the Senate’s Public Safety, Intergovernmental Affairs and Military Affairs Committee, also supports the bill.

"This is a plant that has been used by man, by civilization, for (tens) of thousands of years," he told the Honolulu Star-Advertiser. "And so as people’s attitudes and feelings are changing … people are understanding and seeing that industrial hemp has great potential. And that’s why Hawaii has finally said, ‘OK, we’re beyond the fear and the unfounded concerns. Let’s take a look and see where we can use this to improve, benefit and help our state and possibly the world.’"

Espero (D, Ewa Beach-Iroquois Point) said hemp research is also important because it could pave the way for hemp to be processed as biofuel.

"That area is something that states, countries and nations are all working on, and if we can be a leader … that would be fantastic," he said. "There’s some great economic possibilities and we’ll hopefully be able to take a look at those in the future."

Senate Bill 2175 authorizes the dean of UH tropical agriculture to establish a two-year industrial hemp research program. On a single site, the program would explore how hemp pulls contaminants from the soil, its viability as a biofuel feedstock, and several other factors. A report would be due to the Legislature ahead of its 2016 session.

Harry Ako, a UH professor who will lead the project, said a site has been picked on the Hickam side of Joint Base Pearl Harbor-Hickam where the soil has been contaminated by petroleum products, likely from solvents used to clean off guns.

"We intend to just grow the hemp in the soil and take a before and after (sample) and look at the rate of bio-remediation done by the hemp plants," he said.

Ako also was involved with the state’s first research project 15 years ago.

"My job in those days was to just prove that it wasn’t a hallucinogenic or psycho-­active," he said, later adding: "Probably if you smoked it, you’d get sick."

The three-year project lasted long enough to determine which hemp variety grows best in Hawaii, so researchers this time around wouldn’t be starting from square one. European varieties turned out to be quite susceptible to bugs and birds, Ako said, but Chinese varieties worked well.

The Legislature transmitted SB2175 to Abercrombie’s office Monday, triggering the 10-day countdown to enactment with or without signature, or a veto.

"The governor, along with his staff, relevant departments and the attorney general, will thoroughly review the final language of SB2175 and all bills presented on or before April 14 … in order to make a decision based on their content and merit," said Justin Fujioka, Abercrombie’s press secretary.

Thielen said she’s pleased to see government officials coming around to the idea of commercial hemp cultivation.

She’s been waging a hemp battle for two decades and even met with the head of the DEA once to say "Issue regulations allowing farmers to grow hemp," she said.

A World War II-era poster hangs in her office that reads, "Grow hemp for the war."

She displays a photograph of the first hemp seed being planted in Hawaii in 1999 and has a framed picture of herself standing in a French hemp field. Thielen keeps a hempcrete brick (made of hemp, lime and a binder) on hand to show visitors because she believes being able to use the pest-­resistant hempcrete in construction would mean importing fewer building materials to the isles.

"They have built some public housing (in England) with hemp and I have also been in people’s private homes and it is so climate-controlled," Thielen said. "It is just beautifully comfortable. It would be wonderful for Hawaii, and the idea that you wouldn’t have to worry about termites is a major, major plus."

It was Thielen’s son, who lives on Kauai, who first suggested she sponsor hemp legislation when he saw sugar plantations disappearing and workers losing their jobs.

"I was a little startled and I said, ‘Well, isn’t that a drug?’" she recalled. "He said, ‘No, mom, it’s not. Why don’t you learn about it?’ … I did, and it was an amazing education."

Sen. Mike Gabbard (D, Kapolei-Makakilo), chairman of the Senate Energy and Environment Committee and introducer of the bill, said he, too, was surprised when he learned of the valuable uses for hemp just this year.

"I’m a believer," he said during a phone interview.

Gabbard said his wife has been feeding him hemp seeds in shakes and smoothies for years, but watching a documentary titled "Bringing it Home" and hearing from a constituent before the session persuaded him to take action and introduce a bill. He said hemp can be grown to pull nuclear material and other contaminants out of the soil — such as around the Chernobyl and Fukushima disaster sites — and noted that $550 million in hemp products are imported into the U.S. every year.

"All these things started adding up and I was like, ‘This is just a no-brainer,’" he said.

Thielen said she hopes Hawaii and the 22 other states planning on taking advantage of the 2014 federal Agricultural Act will present their research to Congress in coming years.

"I believe at that point Congress is going to say there’s no reason to have any restriction whatsoever on this crop, and the crop will be able to be just widely grown by farmers," she said.