A common winter forage option utilized in the Upper Midwest is grazing cornstalks. Whether it be in fields or in round bales, cornstalks provide a resource to maintain cows and reduce costs.
“The combination of dropped ears, grain, husks, and leaves provide an adequate ration for spring-calving cows and can be managed to maintain body condition or even add weight with supplementation,” says Taylor Grussing, cow-calf extension specialist at South Dakota State University (SDSU) in an article published on the SDSU Extension iGrow website.
The amount of residue available for cows is dependent upon the amount of grain produced. Each bushel of corn produced per acre equates to about 15 pounds of husks and leaves, which is the most palatable portion of the residue.
If a field yields 150 bushels per acre, then there is 2,250 pounds of husks and leaves for grazing. After taking trampling, wind, and waste disappearance into consideration, there should be enough residue left on 1 acre to support a 1,300-pound cow for about 30 days.
When it comes to managing residue grazing, the first step is to walk the field and clean up any large amounts of grain to reduce the chance of acidosis. Examine fences and relocate water sources to facilitate grazing, which can last from November to January depending on snowfall.
“Cross fencing can be utilized to facilitate strip grazing, which will provide a more balanced ration for cattle over the winter,” advises Grussing. “If residue is not sectioned off, the quality of the ration will deteriorate as winter progresses,” she adds.
As cattle use up resources, supplement a protein source to help maintain rumen function as well as mineral and salt.
Residue grazing can even benefit crop producers. Grazing cattle saves time and money spent on removing excess residue from fields.
When discussing a grazing agreement, be sure to clarify the start and end of grazing, the stocking rate, fences and water availability, and the management of the fences, water, and cattle.
“There is no one-size-fits-all rental agreement for grazing corn residue as it will vary by the needs of both parties,” Grussing explains. The beef specialist explains that if water and fencing are already available, cattlemen she’s familiar with will pay 50 cents to around a dollar per head per day for cornstalks, depending on yield. Residues can also be rented on a per acre basis.
To limit soil disturbance and compaction, Grussing advises to pull cattle from cornstalks once the soil thaws or becomes saturated.
“Similar grazing agreements can be made when grazing cover crops in the spring or fall; yet, the value of cover crops will differ based on quality, quantity, and input costs,” Grussing concludes.
Kassidy Buse was the 2018 Hay & Forage Grower summer editorial intern. She is from Bridgewater, S.D., and recently graduated from Iowa State University with a degree in animal science. Buse is currently attending the University of Nebraska-Lincoln pursuing a master’s degree in ruminant nutrition.