By Charlotte Meeks
Anyone that has managed cow/calf operations for more than a few days can tell you that the most expensive cost is feeding. Grazing is a cost-effective way of providing livestock with their nutritional needs. One method that can extend our gazing season involves grazing crop residue. After a crop (usually corn or cotton) is harvested, crop residue is left in the field until it is plowed under or another crop is planted to take its place. This crop residue can be utilized as part of a rotational grazing system. Grazing crop residue works best in a frontal grazing system, where cattle are continuously moved forward into ungrazed areas.
Things to Consider:
• Check pesticide labels
• Water source
• Weeds/poisonous plants
• Compaction concerns
When grazing a crop residue check the pesticide labels for the pesticides that have been sprayed on the crop. Not all pesticides have a grazing label or may have grazing restrictions. Many of our producers work in a diverse agronomic system of row crops and livestock so many fields in South GA already have permanent fencing to include grazing livestock in their rotation. For areas that do not, movable/temporary electric fencing should be considered. Regardless, movable fencing will be needed to incorporate frontal grazing. There are many options for water sources. Check out the Georgia Forages website (www.georgiaforages.com) for more information. Noxious and poisonous weeds are generally managed in cattle pastures, whereas they are ignored in row crop areas. Before turning cattle out to graze crop residue, note the weeds in the field and check the toxicity to cattle. Soil compaction is a concern when grazing livestock, but the compaction is usually shallow and temporary. Two main factors to consider are soil moisture and soil type. Soils with high clay content and moisture are more prone to compaction than our dry/sandy soils.
In general, quality of crop residues are quite variable and are considered to be a low quality forage that is best suited for dry cows. To make the quality more uniform you can bale the residue, but this is not usually not cost effective. Grazing crop residue also allows for some residue to remain on the field, as well as the manure from the cows. This adds nutrients and organic matter to the soil for next year’s crop. The stocking rate for cattle on corn residue is 1 cow per acre for 60-100 days. As the grazing time increases the quality of the forage decreases. According to the University of Nebraska, 45-50% of above ground biomass is residue. From each bushel of corn produced, 41 pounds of residue is also produced. Cattle are selective grazers and will first consume any remaining grain followed by the husk and leaf. Corn stalks are not palatable with a digestibility of about 35-55% according to Kansas State University.
For cotton the stocking rate is 1 cow per acre for 30-35 days. When cattle graze cotton residue, they consume many byproducts of the cotton harvest including cottonseed, gin trash, and cotton stalks. As study in Georgia showed that approximately 4,500 pounds of cotton residue per acre were left after harvest.
Grazing crop residue also gives our bermuda pastures some rest before winter dormancy. Continuous grazing of bermuda pastures results in poor root development. Allowing the pasture time to rest increases root development which better equips the grass to survive a harsh winter or drought period. While the cattle are moved onto the crop residue, the producer has time to perform fall herbicide applications and to prepare/overseed for winter grazing.
With some fencing and a water source, grazing crop residue can be another option to add into your grazing system.