Corn stalks, alfalfa crops available for grazing after harvest this fallWritten by Saige Albert
As cattle come off summer ranges to their fall and winter pastures, Steve Paisley, UW Extension beef specialist, says that corn residue and fourth cutting alfalfa are options that producers have for grazing cattle.
“Sometimes we also have residue from dry beans,” Paisley adds, “but the way we harvest today, there isn’t as much as far as residue left.”
When grazing cornstalks, Paisley notes that this year, there shouldn’t be as many concerns for producers to worry about as in the drought years seen recently.
“We can always come up with a bad situation, but for the most part, we had a wet year, so we don’t have to worry about nitrates as much,” he comments.
In general, when put on a cornfield to graze, Paisley says cattle will first seek the ear corn and kernels left over from harvest.
“A lot of times, if ranchers have any problems grazing cornstalks it will likely be in the first week because the cattle seek out the grain left in the field,” he explains. “If there was trouble during harvest or there was an area where there was more ear drop in the field, we can have problems.”
After cattle have eliminated the excess corn in the field, they eat the husk and leaves, then work their way down to the stalks and to more course material.
“We typically say that corn is at its best quality when we turn out,” Paisley says. “If we leave cattle out on stalks for a period of time, the stalks and remaining residue are exposed to the elements, so they decrease in quality.”
Because cattle select the highest quality feed first, in some situations they may need supplement toward the latter end of their time on cornstalks.
“If a producers figures they are going to be on the field for 990 days, we save supplementation for the second half of that period,” Paisley describes. “That is when the combination of two things happens. First, the quality of the remaining forage drops. Second, we are getting into colder weather.”
At the same time, the cow’s nutritional requirements increase as she nears calving.
“At that point, the cows can benefit from some protein supplement,” he says.
Grazing fourth cutting alfalfa presents a separate set of challenges, Paisley says.
“Trying to decide when cows can go in on fourth cutting alfalfa is our top concern,” he comments. “We have to wait until the fourth cutting is completely killed.”
If the alfalfa isn’t completely dead, the soluble proteins in the plant can cause bloat in cattle, particularly in calves and yearling cattle.
“Weaned or young calves seem to be much more susceptible to bloat, and if we turn them out too soon, that is the perfect scenario to see problems,” Paisley explains.
After a partial freeze can be more damaging, he continues.
“If alfalfa has gone through a partial freeze, the cells are ruptured,” Paisley says. “That makes the soluble proteins that cause bloat more accessible. A partially frozen field provides high risk.”
Before turning cattle out onto the fourth cutting of alfalfa, Paisley encourages producers to make sure the crop is completely yellow and dead.
Finally, if any questions or concerns remain, Paisley encourages producers to contact their local Extension specialist for more information.