Frost Won’t Hurt Crops in 2010

Published on: 07:29AM Oct 12, 2010

When entering the fall season, farmers often become weary of an early frost that can lead to crop damage and yield loss. This fall, frost concerns are minimal as farmers were able to get into their fields in early spring and crops matured ahead of schedule due to favorable weather during the growing season.

For farmer’s schedules, frost is the limiting factor for both planting and harvesting. If farmers plant their crops early and frost hits when the plants are small and emerged, the frost could affect development and lead to yield loss. On the other hand, if frost arrives before the crops are not fully mature, yield loss will also transpire as the plant may no longer be able to grow. A damaging, hard frost occurs when temperatures reach 28 degrees Fahrenheit, according to Iowa State University.

Growing degree days (GDD) dictate how fast corn matures, while moisture levels dictate when farmers harvest. The warmer a day is on average, the more GDD units the crop receives. Typically in fall, farmers are hoping to squeeze in every last GDD before the first frost strikes.

For farmers in the Corn Belt, October is corn harvesting season. In early October, corn kernels can dry down about 0.50% to 0.75% per day in good weather, according to Iowa State. In late October, kernels will only dry down about 0.33% per day. The ideal harvest moisture for corn is around 15%.

The average first fall frost varies as the further North you travel. In Cedar Rapids, Iowa the average first fall frost occurs on October 7th, giving the area a 161 day growing season, according to the Farmer’s Almanac. About 300 miles to the North, Bismarck, ND receives its first frost on September 20th on average, giving the region about 129 days to its growing season.

2010’s Difference

The planting season started early for the Corn Belt in 2010. The warm spring lead to an early thaw and fields were dry and ready to be planted as soon as crop insurance allowed farmers to start. Since crops were planted early, and favorable weather was present throughout the summer, corn matured quickly. In the end of May, 71% of the U.S. corn crop had already emerged compared to the 5-year historical average only 62%, according to USDA Crop Progress Reports. In mid-August, 74% of the corn crop had entered the dough stage, compared to the 5-year historical average of only 58%. Throughout the 2010 growing season, crops were well ahead of schedule.

Since this season has allowed corn to mature faster than in previous years, some agriculture specialists feel that the crop may have actually matured too quickly and may suffer some yield loss. If the weather continues to remain favorable and dry, expect farmers to finish their harvest early, and move right on to fall tillage in preparation for the 2011 season.

Often an early frost will send grain prices on the rise because of the risk of lower production. Recently, we have seen a rise in grain prices, but not because of frost concerns, rather decreased production estimates due to the fast maturity of the corn crop and unfavorable weather in August. The most recent USDA WASDE Report from last week estimated the average U.S. corn yield at 155.9 bushels per acre compared to last year’s 162.5.

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