NEW YORK (Bloomberg) — Insurance claims filed by US farmers for crops they couldn't plant have jumped 48 per cent this year, government data show, the latest indication of how adverse weather is curbing production of corn and other crops.

Total claims so far in 2015 related to 6.45 million acres (2.61 million hectares), the US Department of Agriculture's Farm Service Agency said in a report.

Corn farmers filed claims on 2.301 million acres, compared with 1.608m acres a year earlier. Soybean farming claims more than doubled to 2.17 million acres. Corn and soybean futures prices rose in early Chicago trading.

“This reduction in acres takes production down,” Michael McDougall, senior vice president at Societe Generale in New York, said in an e-mail. “This caused the early morning firming in prices.”

Harvests in the US, the world's largest grower and exporter, are heading for a decline after two successive record years. The growing season began with higher-than-normal moisture in parts of the Midwest, followed by unusually dry weather in other areas.

While there's agreement that output will be lower in 2015, estimates differ over the extent of the decline. Last week the USDA unexpectedly raised its corn and soybean output estimates from a month earlier, citing higher yields than those seen previously.

On Monday corn for December delivery was 0.1 per cent lower at $3.75 a bushel on the Chicago Board of Trade after earlier rising as much as 1.1 per cent. Soybeans for November delivery rose 0.3 per cent to $9.19 1/4 a bushel, erasing earlier losses.

The record payout to farmers who didn't sow crops took place 2012, according to USDA data. Growers are required to file a report on all cropland eligible for benefits.