Corn futures surged more than 20% to a three-year high over the past few weeks on fears farmers wouldn’t be able to get seeds in the ground ahead of crop-insurance deadlines. So-called prevented plant claims reached 3.6 million acres in 2013, according to the U.S. Department of Agriculture’s Farm Service Agency.

Field conditions deteriorated over the past few weeks, indicating significant corn acreage loss was a risk, according to Gro Intelligence, a New York-based analysis firm that uses satellites among other data sources. Areas with the biggest risk of acreage loss were in central Illinois, Indiana and Ohio, and the region around the borders of South Dakota, Minnesota, Iowa, and Nebraska.

Such insurance claims are considered a last-ditch effort for farmers, who can receive about half of the value of their crop. Analysts in the Bloomberg survey cautioned estimates could still be skewed by the weather and the government’s market facilitation program, a $16 billion aid package to mitigate the impact of trade wars. Soaring corn prices could also prompt farmers to plant the crop without insurance.“The MFP payment is dependent upon acres being planted,” said Karl Setzer, market analyst at Agrivisor in Bloomington, Illinois. Setzer estimated that 4 million to 5 million acres of corn could be left planted. However, “the recent rally in futures will also encourage planting beyond normal dates,” he said.