THE BURNED OVER DISTRICT

Industrial hemp is truly the plant with a thousand uses andall of them stifled in this country because of that flaming asshole Harry Anslinger. What few products are found in this country are made from foreign grown hemp and the profits sent overseas.

The Romans have been using it since the days of Julius Caesar, but not to get high. Both Washington and Jefferson grew it.

Now that several states have legalized the use of marijuana for some recreational and medical purposes, one of the biggest untapped markets for the cannabis plant itself — at least one variety — could be as a building tool.

The most sustainable building material isn’t concrete or steel — it’s fast-growing hemp. Hemp structures date to Roman times. A hemp mortar bridge was constructed back in the 6th century, when France was still Gaul.

Now a wave of builders and botanists are working to renew this market. Mixing hemp’s woody fibers with lime produces a natural, light concrete that retains thermal mass and is highly insulating. No pests, no mold, good acoustics, low humidity, no pesticide. It grows from seed to harvest in about four months.

A strain of the ubiquitous Cannabis sativa, the slender hemp plant is truly weedlike in its ability to flourish in a wide variety of climates, growing as high as 15 feet and nearly an inch in diameter. The plant’s inner layer, the pith, is surrounded by a woody core called the hurd. This is the source of the tough fiber, which can be used for rope, sails and paper.

Hemp is typically planted in March and May in northern climes, or between September and November below the Equator. Once cut, usually by hand, plants are left to dry for a few days before they’re bundled and dumped into vats of water, which swells the stalks. Those dried fibers are then blended for a variety of uses, such as adding lime. This creates block-like bricks known as hempcrete.

Industrial hemp contains a mere 0.3 percent of THC (tetrahydrocannabinol), the substance responsible for the buzz when smoking weed. The cannabis present at a reggae fest, for instance, contains as much as 20 percent.

The two strains look different, too. Hemp’s sativa is taller; the shorter indica has resiny trichomes accounting for its psychoactive power. The rule goes: the better the budding flower, the poorer the hemp.

Also unlike pot, you can’t grow hemp in an indoor hydroponics setup; the plant’s deep roots need to spread, so outdoor cultivation is required. The plant’s seeds and leaves can be eaten raw, dried into powder or pressed into oils.

Getting a mature plant in just a few months — with less fertilizer than needed for industrial crops like corn, and without chemical fertilizers or bug sprays — makes the potential for profit huge. As hemp taps water underground, its long roots circulate air, which improves soil quality — another boon for farmers looking to rotate crops.

Battling the plant’s powerful drug connotation might be the toughest hurdle for farmers and builders, and is possibly a more formidable obstacle during the Trump administration. The plant is still highly regulated.

This January, though, California legalized use of the plant in full. And the federal farm legislation of 2014 legalized hemp’s cultivation for research purposes in universities in states where it’s been approved by law. New York now funds a research initiative for as much as $10 million in grants toward hemp businesses, with participation in the pilot program from institutions that include Cornell University.

Still, in the United States special permits are needed to build with hemp, and the requirements can vary by county and state. The first modern hemp house was constructed in 2010, in North Carolina. There are now about 50 such homes in the country.

During World War II hemp prohibited status was lifted because the navy needed rope and hemp made the best. But when the shooting stopped, the hemp competition got the ban reinstated and know-nothings at all levels of government have kept it that way. It is time for this to stop.