A. Planting and Early Growth Conditions–Spring (March–May)
Early planting was adversely impacted by cold temperature snaps and no rain
Weather factors impacting corn yield and quality include the amount of precipitation and the temperature just prior to and during the corn growing season. These weather factors interact with the corn variety and the soil fertility to influence final grain yield and quality. Grain yield is a function of the number of plants per acre, the number of kernels per plant, and the weight of each kernel. Cold or wet weather at planting could reduce plant numbers or hinder plant growth, both of which would produce lower yields. Some dryness at planting time is beneficial, as it promotes a deeper root system to access water later in the season. Extreme dryness during the first few weeks of growth, on the other hand, may lead to “rootless” corn in which the plants do not form a fully normal root system and may be vulnerable to heat and moisture stress and nutrient deficiencies later in the growing season, even if conditions subsequently improve.
In contrast to 2011 when planting was delayed due to a cool, wet spring, a record-setting warm March and dry spring this year encouraged early planting. Following the early planting, three significant waves of cold air and freezing temperatures (on April 5-7, 11-12, 27) in the Midwest hindered plant growth.
The warm and dry early spring conditions jump-started the 2012 corn crop. As a result, 96% of the corn was planted by May 21 (15% ahead of the five-year U.S. average), while emergence was at 76% (28% ahead of the five-year U.S. average). Earlier planting is beneficial because farmers want the corn plant to be as large as possible in the long days of June and July.
Unfortunately, however, by the end of May, more than half of the Southern Rail and Gulf ECAs was abnormally dry, setting the stage for this past summer’s drought.