Do you have downed corn?

Take time to evaluate, make adjustments

Tony Nye - OSU Extension

Harvest has been moving right along now with hopes that it will continue with little delay. The weather lately has been very cooperative.

Locally, several acres of both soybeans and corn have been harvested. There are some reports early that certain corn fields have had lodging issues. This goes along with what has been reported throughout the state the last week or so.

Generally stalk quality is the issue and with the number of reports we are hearing, this is probably not a year to “store” corn in the field as some say. In fact, Peter Thomison, Ohio State Corn specialist, suggests stalk rots are largely responsible for the problem which has been promoted by stressful production environments and susceptible hybrids.

Affected corn stalks are characterized by internal plant tissue that has disintegrated and often appears “hollowed out.” These symptoms are also often present in the crown of the plant.

Severe lodging slows the harvest operation causing delays that expose the crop to less favorable weather conditions, as well as wildlife damage. Another loss may occur if ear rots develop when ears on lodged plants come in contact with wet soils and surface residues. Even certain hybrids that normally exhibit good stand ability and stalk quality are exhibiting significant lodging.

Thomison reports that some grower accounts have noted corn that had been standing well, collapsed in the course of a few days. In these extreme situations, growers may face major challenges harvesting lodged corn which is nearly flat on the ground.

Thomison shares some tips that experts agree throughout the industry as standards that should be followed when dealing with downed corn. The following tips are taken from a fact sheet by Dr. Mark Hanna, an extension agricultural engineer in agricultural and biosystems engineering at Iowa State University, “Harvest tips for lodged corn”

First of course is to scout fields to determine where problem areas are and the condition of stalks and ears. Harvest the problem areas first when field conditions are better and before kernels in close proximity to the ground have an opportunity for potential further deterioration.

An exception might be made to harvest an area with particularly weak stalk strength that is still standing if the odds of lodging from weather seem high.

The only way to evaluate whether any harvesting aid or technique is helping is to measure harvest losses. Keep in mind each ¾-pound ear on the ground per 436 square feet equals a loss of one bushel per acre. Be prepared to get out of the combine and check for harvest loss in these situations.

Many of you are connected to web by way of your smart phones – check out a great fact sheet by Iowa State, Profitable Corn Harvesting. This fact sheet provides easy ways to measure harvest loss.

For example: Use a rectangular frame enclosing 10 square feet. Every 20 kernels of corn found within the frame is approximately equal to 1 bushel per acre loss. For ease, take a measuring tape to the field at harvest and spend a few minutes behind the combine checking losses.

Other suggestions by Thomison are to look at the machine itself to reduce losses as follows:

• Set gathering chains for more aggressive operation with points opposite each other and relatively closer together. Adjust deck plates over snapping rolls only slightly wider than cornstalks so that they hold stalks but not so narrow that stalks wedge between the plates.

• Operate the head as low as practical without picking up rocks or significant amounts of soil.

• Single-direction harvesting against the grain of leaning stalks may help. Evaluate losses though before spending large amounts of time dead-heading through the field.

• Limited field measurements suggest a corn reel may or may not help limit machine losses; however, a reel likely allows greater travel speed and improves productivity. Losses may be similar comparing harvest at 1 mile per hour without a reel and 3 miles per hour with a reel, but harvest goes much faster. Spiral cones mounted atop row dividers or the addition of higher dividers on each end of the corn head are other potential after-market harvest aids.

• If harvest speeds are significantly reduced, the amount of material going through the combine is reduced. Fan speed may need to be reduced to avoid blowing kernels out of the combine. Rotor speed may need to be reduced to maintain grain quality. Check kernel losses behind the combine and grain quality to fine tune cleaning and threshing adjustments.

Grain platforms have been used to harvest corn in relatively severe cases. More cornstalks and material other than grain enters the combine. Expect capacity to be reduced somewhat. Concave clearance may need to be increased for increased throughput and fan speed may need to be increased to aid separation in the cleaning sho

Perhaps as important as anything, get into the correct frame of mind and keep the right mental attitude. Recognize that speeds will be slower. Communicate these expectations with others. Don’t allow an accident to compound harvest problems.

Take some time to make adjustments; commodity prices are lower than in the past so margins may be smaller as well. Every dollar counts, so take some time to evaluate, adjust, and slow down.

Tony Nye is the state coordinator for the Ohio State University Extension Small Farm Program and has been an OSU Extension Educator for agriculture and natural resources for 28 years, currently serving Clinton County and the Miami Valley EERA.
Take time to evaluate, make adjustments

Tony Nye

OSU Extension