Around Heihe, some growers are trying to modernize in other ways.

Hou Wenlin started the Linfeng Modern Agricultural Specialty Cooperative in 2014. He does not believe that China will be able to replace soy imports entirely.

“There’s no point,” Mr. Hou said. “It just can’t be done.”

He does, however, believe that China can grow soybeans more scientifically. In one of his cooperative’s fields, the soy grows in neat rows that are spaced farther apart to keep the plants at the right temperature and moisture. Each season, he plants a number of different types of seeds to understand how each performs. He has two drones for spraying pesticide.

Modern farming is expensive, however. And in Mr. Hou’s case, it involves a secret weapon: American technology.

In front of the cooperative’s office is a yard full of bright-green John Deere farm machines, which Mr. Hou buys with the help of government subsidies. Chinese machinery is cheaper but more prone to breakdowns, he says.

Even some of the fertilizer Mr. Hou uses comes from the United States.

The Chinese equivalents are better now than they used to be. Earlier, though, there was something that was commonly said, according to Mr. Hou, among farmers around here who knew the chemical name of one of the most widely used plant foods:

“We rely first on the heavens,” the saying went. “We rely second on American diammonium phosphate.”