Strange Pollination Patterns Showing up in Corn Fields

If enough are is affected, yield could be impacted in that field.

Published on: Aug 22, 2011

Those who are lucky enough to have planted on time and had enough rain, and especially those who escaped the incredible heat wave that covered mid-July through early August, may have escaped kernel set problems. If you're one of those people and you've checked enough ears to know that they look normal, especially if they're big and girthy and you've got a good population, congratulations! You've probably got a good crop on the way. But before you make further marketing decisions,. Perhaps you should read on to find out what is being found in very stressed fields, many in the central to eastern Corn Belt, form parts of Illinois eastward through Ohio. Indiana fields, especially the eastern half of Indiana and western side of Ohio, may be the epicenter of poor pollination.

If you're one setting with fields that you know have problems, your concern may be have you8 contracted too much corn already. What was a good decision at the time can become haunting if you don't get good yields, or at least enough to fill your contracts.

Bob Nielsen, Purdue University Extension agronomist, says he's getting several reports of fields where at least a portion of the ears have 'outgrown' the shucks. The cob length may be similar to ears that are normal with normal husks, but the shucks quit developing prematurely, and the top inch to three inches of ear may be exposed.

The likely cause is stress. The more the stress, whether from root lodging or heat or drought, or all three, the more likely the condition. Nielsen says it typically is noticed most in years when there is a stress like there was this year, and then after pollination it turns cooler and rains. It turned cooler after early August. Whether it rained or not depends upon where you live.

The problem with these ears is that the exposed portion is unprotected, and subject to bird damage. It also makes it susceptible to molds, since the tip kernels are exposed. Some of these factors may cause yield loss, but the real loss due to this condition can occur if there is enough of it in one field to result in moldy or damaged kernels in enough quantity to lead to a dock at the elevator, Nielsen says.

You may also find what Nielsen calls 'zipper' ears. One or more rows on one side of the ear fail to develop. Why they fail to develop is not clearly known. It typically runs the entire length of the cob. Nielsen believes the condition is also related to stress. What you typically wind up with is a nubbin-size ear which is missing rows on the bottom. It may cause the ear to have an odd shape as well.

A number of these types of problems and the more common tip-back abortion or poor kernel set are being reported in areas hit the worst by mid-season drought and the heat wave during pollination and early grain fill, Nielsen notes. Before you head back to marketing grain, you may want to factor in this element, no matter which side of the fence that you are on.