It seems like just yesterday, farmers were pulling that last load of grain out of the field. Cows were just starting to be turned out on cornstalks and then, wham! Snow, cold and winter is upon us. While I appreciate a white Christmas just as much as the next guy, a large amount of snow this early in the season can create difficulties for producers who were planning on grazing corn residues.
The first thing we need to be aware of when dealing with a snow covered corn field is the physical impact snow has on cow foraging. A general rule of thumb is with over 6 inches of uncrusted snow or ½ inch of ice, cows start to have difficulty reaching residue to eat. Some things, like the quality of snow received, can throw off our 6 inch rule. Heavy, wet snow is harder to move than the light, fluffy stuff. This last storm was wet, with well over 6 inches accumulating in some areas and ice buildup in others. In these conditions, supplementing animals until the snow settled enough that grazing could again occur unimpeded was a good strategy.
Another physical factor that needs to be watched is crusting. As the snow settles, it may compress below 6 inches in height, but in most places, a firm crust forms, which still prevents cattle from getting to the residue below.
Beyond physically preventing animals from reaching the residue below, winter weather can also impact the quality of what’s being grazed. While snow might melt off later on this winter to allow easy access by cows, the quality of the residue remaining will be decreased. This comes in two forms. First, wet conditions with unfrozen ground increase the chances for residue to be trampled and muddied, making it unavailable for animal consumption. Secondly, both rain and snow cause leaching of sugars and other nutrients from the residues. These nutrients provide the energy and protein needed to meet animal requirements. Less of these means lower quality forage. With a wet fall this year, molds and fungus may have begun growing in the residue, stealing away even more nutrients to fuel their own growth, and decreasing feed value even further.
While weathered corn stocks aren’t unusable, they may require little extra work to utilize well. Producers need keep a closer eye on their animals and provide extra supplementation a bit earlier than they normally would. If multiple fields are available for use, another option to maximize their potential would be to graze hard and fast. Concentrate animals into one larger group and switch fields quickly. The animals will use the residues that are readily available, then get moved to a new field before performance suffers as quality residue becomes more difficult to find.
While snowy conditions make utilizing corn stocks for winter feed a bit more difficult, they are still a very economic option to consider. A bit more effort may be required of the producer to assure proper use and prevent a drop in animal condition, but with the right management, corn residues remain a grazing option we can continue to utilize well into the winter months ahead.
-Ben Beckman is a beef systems Extension Educator serving the counties of Antelope, Cedar, Knox, Madison and Pierce. He is based out of the Cedar County Extension office in Hartington. You can reach him by phone: (402) 254-6821 or email: ben.beckman@unl.edu .