This battle is decidedly, and Midwesternly, pragmatic: In 1993, scab — a fungus also known as Fusarium head blight — tore through this region, wiping out thousands of acres of wheat, one of the prized crops in North Dakota, where agriculture remains the largest element of the economy. Hard rains left water pooling in fields, giving the scab an opening. It has turned up in varying degrees ever since, even as farmers searched for a cure. On a recent afternoon, as rain pounded his 710 acres, Mr. Monson gloomily yanked the head off a stalk of his wheat, revealing for a visitor whitish, shriveled seeds — the telltale signs of scab.

When Mr. Monson began his efforts in the late 1990s, some here balked. He remembered John Dorso, a former Republican leader, rolling his eyes and asking Mr. Monson if he knew what he was getting mixed up in.

But hemp, Mr. Monson argued, offered an alternative for North Dakota’s crop rotation. Its tall stalks survive similarly cool and wet conditions in Canada, just 25 miles north of here, where it is legal. And it suits the rocky soil left behind here by glaciers — soil that threatens to tear up farm equipment for anyone who dares to plant crops like beets or potatoes beneath ground.

Years and studies and hearings later, few here have much to say against hemp — a reflection, it seems, of the state’s urgent wish to improve its economy. Recent hemp votes have passed the legislature with ease, though some questions linger. How big a market would there really be for hemp? What about the worries of drug enforcement officials, who say someone might sneak into a farmer’s field of harmless hemp and plant a batch of (similar-looking) marijuana?

Such fears, Mr. Monson insisted, are silly in North Dakota, which is the 48th most-populous state, with fewer than 640,000 people. This is the only state where voter registration is not required. (Everyone would know, the logic goes, if someone who did not belong tried to vote.) “You can’t go down to get the mail around here without someone knowing,” Mr. Monson said.

But Blair Thoreson, a Republican state representative who has voted against hemp measures, is less sure. “Everyone here knows everyone,” Mr. Thoreson said, “and yet we’ve had a huge problem here with homegrown methamphetamine labs, too.”

Roger Johnson, the state’s agriculture commissioner, said hemp fields would be the worst places to hide marijuana. Under state rules, he said, such fields must be accessible for unannounced searches, day or night, and crops would be tested by the state. Also, he said, a field of hemp and marijuana would cross pollinate, leaving the drug less potent.