October 01, 2002

LINCOLN, Neb. — With Nebraska pastures depleted by drought, hay prices high and supplies tight, using cornstalks to their fullest could be especially important this winter for cattle producers, said Bruce Anderson, University of Nebraska forage specialist.

More than 10 million tons of crop residues from corn production will be available following combining the grain crop. That's enough to feed all the beef cows in Nebraska through the entire winter two times, Anderson said.

"These residues can provide a valuable forage for beef cattle this winter to replace forage lost due to the drought," Anderson said. "They also can stretch the supply of higher quality hay such as alfalfa."

Grazing is the easiest way to take advantage of corn's forage value, but baling or chopping also are options.

Producers should start grazing stalks as soon after harvest as possible to relieve pastures stressed by the drought, the Institute of Agriculture and Natural Resources specialist said.

"Grazing cornstalks right away will put more condition on cows and faster gains on young stock," Anderson said. "Grazing pastures hard this fall will only make them worse, and cornstalks' nutrient value will decline the longer they are exposed to weather."

Normally, producers graze cattle on the whole field. With average cornstalk production, one cow can graze one acre for about 45 days. However, drought stress, grasshopper feeding and hail reduced grazing capacity on many fields this year.

Strip grazing – fencing off portions of a field or moving cattle from field to field – may be a better strategy this year. Strip grazing reduces trampling waste so the number of cow days of grazing per acre can increase.

Producers also need to be careful about extra grain left behind by the combine. It can be a bonus for cattle grazing, but too much grain can cause health problems.

Anytime more than about eight bushels of grain per acre are left in the field after harvest, cattle grazing the stalks risk getting acidosis and founder.

Both ailments are caused by excess grain intake, which increases rumen acid production. Both can cause foot and hoof problems, including lameness.

Before turning cattle out for the first time, fill them with hay so they don't eat too much of this new feed right away.

Early on, dry cows will at least maintain body weight and may gain a 1/2 to 1 pound per head daily while grain, husks and leaves are available. After grain is gone, cows can lose condition unless supplemented.

Since cattle and cornstalks can be miles apart, another strategy might be to bale or chop corn residue and haul it to the cows.

There are many methods, such as copping into a stack wagon or cutting, raking and baling. However, these methods remove most of the stalk reside, which is valuable for erosion control, Anderson said.

"A better method might be to start by removing the chopper from behind the combine," Anderson said. "Let the husks, leaves, escaped grain and other tailings fall directly behind the combine. Then round bale, square bale or stack this strip of residue but leave everything else."

These bales should have between 50 percent and 60 percent total digestible nutrients. Protein might be only 5 percent, but with a little protein supplement, cows could actually get fat eating these residues, Anderson said.

Fields with heavy grasshopper or hail damage may have less feed value than undamaged crops or irrigated fields. Before feeding, sample and test bales or stacks for protein, energy and nitrate levels to formulate rations that will be safe to feed.

For more information on using corn as forage, visit NU Cooperative Extension's Beef Cattle Production Web site.

10/02/01-SA

Bruce Anderson - Ph.D
Agronomy
Professor
(402) 472-6237

Sandi Alswager Karstens
IANR News and Photography
(402) 472-3030

Department: Agronomy & Horticulture