Corn harvest is ongoing in many parts of the country and cows are starting to graze the stalks. How should this grazing be managed to get the most out of them?
One of the most important decisions in all grazing situations is stocking rate, including corn stalks. Fortunately, you can get a good estimate for corn stalks by dividing the corn grain yield by 3.5 to estimate grazing days per acre for a 1,200-pound cow.
So, for a field that yielded 210 bushels per acre, dividing 210 by 3.5 gives 60 grazing days per acre. Thus, a 160-acre field could provide 9,600 cow grazing days.
One possibility is to graze 60 cows for 160 days. Starting here at the end of October, that could take you all the way through March. Sounds pretty good but how will this work nutritionally? Cows will eat the best feed first, any downed grain and the husks. After a couple months, all that will be left are stalks and leaves that have been walked over, rained or snowed upon. Without a lot of supplements, these cows will be in very poor shape by the end of March.
Clearly, shorter grazing periods are needed. Maybe, instead of 60 cows for 160 days you graze 160 cows for 60 days. Better, but you still may need supplements near the end of the 60 days. Better still would be to give those 160 cows just one week’s worth of the stalks to start, a little over 18 acres. By day 6 and 7 those 160 cows will have cleaned up just about everything, but on day 8 you give them a fresh 18 acres, returning them to high quality feed without so much supplement.
Both stocking rate and changes in the quality of grazing with time need consideration as you plan and manage stalk grazing. Do it right and corn stalks become a great winter feed resource. ~ Bruce Anderson, MyCentralNebraska.com