The Corn Feed

As a result of the current record-breaking heat throughout the U.S., farmers who were forced to plant corn later in the season due to heavy spring rains may be noticing signs of heat stress and reduced yield potential.

Peter Thomison, corn scientist at The Ohio State University Extension, says that because of the wet spring, corn was either planted early or late this year. In Ohio alone, it’s estimated that 30 to 40 percent of the corn crop was planted in mid-May, while the bulk was planted after Memorial Day.

“Given the variability of corn in the fields, some of the later corn isn’t rooting very well because of soil conditions at planting – things like sidewall compaction and varying planting depths,” said Thomison. “Because of the intense heat and lack of rainfall this summer, some of that corn isn’t performing well, even though it was planted in a moist soil bed. Some of this corn could be six feet tall, and in the same field there’s corn waist high.”

The high temperatures and reduced moisture in the soil can also wreck havoc during tasseling, as corn’s water use is highest during this stage. Thomison suggests that the combination of high temperatures and the lack of water could result in sizable kernel abortion after pollination. While the ovules may still get pollinated, the lack of moisture will cause the kernels to abort – prompting tip dieback.

Across the U.S. the forecast for August shows average or below average rainfall and more high temperatures, ensuring this issue will remain paramount.

Read Thomison’s full comments on the subject in this AgWeb article.