NEW YORK, United States (AFP) — Months without rain have left farmers across the vast United States Midwest, part of the country's essential "breadbasket," seeing crop yields in freefall, with some fields too damaged to harvest.

At the 4,000-acre (1,600-hectare) Tucker Farms in Venango, Nebraska, "we were only able to harvest… around 500" acres, most of it wheat, Rachel Tucker said.

Much of the rest had shriveled up under a relentlessly hot sun.

The drought has attracted grasshoppers, which threatened the flowers the Tuckers also grow — until they brought in praying mantises to control the winged pests.

If the American West has been suffering through water shortages for years, the Midwest has not seen conditions this bad since 2012.

"It's even worse than 2012," Tucker said. "Much worse."

The story is just as grim to the south, in western Kansas.

"I was catching up with some older farmers this morning," Marc Ramsey, whose family has farmed near the small town of Scott City for nearly a century, said.

"Guys that are in their 70s and 80s are saying, you know, they haven't even experienced anything like this in their lifetime. So it's pretty bad."

Rainfall has been almost nonexistent since late July, he said. Two inches "was all we've had, basically all year."

Dwindling groundwater

Drought has hit the three major US crops: wheat, corn and soybeans, and the US Department of Agriculture recently had to lower its nationwide yield predictions.

Along With Kansas and Nebraska, the Midwestern state of South Dakota has also been hard-hit.

In normal times, these three states provide one-third of US winter wheat production, and one-fourth of the corn output.

Approximately 30 percent of Marc Ramsey's land is irrigated and, meaning that portion is doing better than his other fields. Tucker Farms' single irrigated field also fares better than the others.

But even some of Ramsey's irrigated fields are producing only 80 bushels of corn per acre, less than half the usual rate.

High levels of water usage have led to "pretty dramatic declines" in aquifers across western Kansas, Buchanan said, adding that farmers in some areas "have really struggled."

"They've seen some wells go dry. They've had to return to dryland farming," meaning without irrigation.