DES MOINES, Iowa (AP) — A freeze could stop the growing season in the upper Midwest as far south as Nebraska and Iowa, leaving farmers in a difficult situation because much of the region's corn and soybean fields are not quite ready for harvest.

The area of most concern includes Minnesota, North Dakota, South Dakota and Wisconsin, where just 40 percent to 50 percent of the corn crop is mature, but a U.S. Department of Agriculture meteorologist says a freeze could reach as far south as Iowa and Nebraska. A hard freeze would stop growth, leaving the crop underdeveloped and lower in quality.

In some areas of Iowa and Nebraska corn and soybeans were planted weeks later than normal due to spring storms. Agronomists say fields need more time to dry before they're harvested.

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