Over the past three years, Mike Yoder made a name for himself in rural Ohio selling a spray-drone trailer kit that saves farmers money and weeks of labor by dropping seeds, fertilizer and fungicide from the sky.

But Mr. Yoder’s company, nuWay Ag, has been struggling since last winter, when it became far more difficult to import drones made by a Chinese company, DJI, into the United States.

DJI, the world’s largest manufacturer of commercial and industrial drones, is on the verge of being banned in the United States by federal lawmakers who accuse the company of a variety of infractions, including using forced labor, benefiting from unfair subsidies and being a cybersecurity threat.

Mr. Yoder recently had to let go of two of his 22 employees because he couldn’t get enough DJI drones to sell to make payroll.

The looming ban is part of a push to decouple the U.S. economy from China’s. It comes as artificial intelligence is transforming what drones can do, and as American manufacturers struggle to get a share of a growing market. DJI commands roughly 75 percent of the consumer market globally and is known for making drones that buyers say are affordable, easy to use and full of bleeding-edge features that save time and money.

Construction companies use specialized DJI drones to monitor the progress of skyscrapers and submit automatic reports. Mining companies use DJI drones to calculate the output of mines. Land surveyors use drones with high-quality lenses to create detailed maps of terrain. Police officers use thermal drones to find lost children and fleeing suspects.