Corn Stalk Grazing Calculator is available to help determine the number of acres at a certain corn yield needed for a certain number of cows.
It seems that annual cow costs get higher each year, or at least they can potentially increase each year. This year is no exception. Drought has increased forage prices nationally. There are some management practices that are essential to consider this year. Having the cows graze to meet their nutrient needs is less expensive than having to carry harvested forages to them. Crop residues, such as cornstalks, can also be an inexpensive option.
When grazing residue, cattle will select and eat the grain first, followed by the husk and leaf and finally the cob and stalk. Because of this selection process, the cornstalk residue diet consumed could be very high in energy content (70% TDN) at the first of grazing, to low (48-52% TDN) at the end of grazing. Also, as the stocking rate (number of cows per acre) increases, the nutrient content of the residue declines more rapidly as the grain and husk are being removed at a much faster rate.
In the Midwest, weather records indicate the range in number of continuous grazing days for crop residue is 65-111 days. Weather can be the most important factor in successfully grazing crop residue.