What ate my corn?
Wildlife damage to corn is common in Michigan. Consider these tips for growers to determine which species causes what type of damage.
Deer will begin feeding on or tramping down corn starting at emergence. As long as the growing point remains undamaged, the plant will continue to grow to growth stage V5. From V6 to prior to tassel, deer browse leaves. Deer damage during this time can be a complete bite of the stalk below the tassel and at the center of the growth whorl.
Damage to ears during their development causes a telescoping husk as they mature. Feeding on young ears during late vegetative growth will, of course, result in near entire loss of yield for that plant.
During corn reproductive stages, deer damage is concentrated during the silk stage, milk stage and maturity. During silking, deer bite the tender corn silks. The impact on yield during this depends on whether or not the damage occurred prior to pollination. Feeding usually occurs before pollination because the silks quickly dry out after pollination. Silk feeding prior to pollination impacts yield.
During the milk stage, deer remove kernels by using their lower incisors (teeth) to scrape an ear along its length. They can also knock down mature corn stalks. Signs of deer damage include a small number of stalks knocked down and lying in the same direction. This damage is usually caused by deer running through the area rather than feeding on the corn.
Raccoons damage corn by climbing the stalks and breaking them to reach the ears, pulling back the husks and partially eating the cob. Damage almost always occurs after the corn has begun its reproductive stage and continues until harvest. Corn damaged by raccoons will lie down in many directions, and the number of stalks knocked down is typically more than deer will knock down. Raccoon damage to corn results in shredded husks and muddy cobs.
Wild turkeys may be blamed for crop damage, but this is not usually the case. They are most likely consuming insects and waste grain and not causing the initial damage.
While groundhogs will damage soybeans, they are not typically responsible for much damage to corn.
For a more in-depth look at this topic, read Purdue University Extension’s publication on “Corn and Soybean Crop Depredation by Wildlife.”