July 22, 2002

LINCOLN, Neb. — Producers in areas of Nebraska with drought-stricken dryland or water-limited irrigated corn may want to get what they can from their crop by using it for forage, haying or grazing, a University of Nebraska forage specialist said.

Using the damaged corn can provide livestock feed and reduce grazing of already short pastures, said Bruce Anderson, Institute of Agriculture and Natural Resources forage specialist.

Nutritionally, this drought-damaged corn is adequate for beef cows – with or without suckling calves, replacement heifers and steers. Small, weaned calves may struggle at first with grazing corn as well as with eating unground hay, Anderson said.

However, there are several considerations before producers feed their drought-stressed corn.

Drought-stricken corn can contain high levels of nitrate, which can sicken or kill cattle Anderson said. Producers may need to harvest the corn differently or mix feed rations differently, he said.

Corn can be harvested as hay – similar to cane hay, with a thick, slow drying stalk – but may be difficult to harvest, to keep bales together and to determine nitrate content.

"Testing is a must and cutting at taller stubble heights will help reduce nitrate contents," Anderson said.

Chopping corn for silage is an excellent choice for reducing nitrate problems. Silage can neutralize nitrates by about one-third. But silage doesn't transport well, making it a poor choice unless livestock are near.

Nitrates also can be a worry with grazing if the animals are forced to eat the lower stalks. A bigger challenge is fencing and water since most fields do not already have these. Proper management, such as strip grazing, is needed for efficient use of the corn. Otherwise cattle will trample and waste a large portion of the crop, Anderson said.

"However, greenchop is the most hazardous feed to use when nitrates are high," he said. "Never allow greenchop to sit in feed bunks or feed wagons and heat."

During the heating process, nitrates get converted into nitrites, which can be 10 times more toxic than nitrates, he said.

"To avoid this, only chop and feed what the animals will eat in a single meal," he said. "To further minimize nitrate risks, leave a tall stubble in the field."

Using insecticide treated crops for forage and feed also can be a problem, said Tom Hunt, entomologist at NU's Haskell Agricultural Laboratory near Concord.

"Read the insecticide label when treating for grasshoppers and other insects in crops that may be used for forage or feed," he said. "Restrictions vary for different insecticides."

Producers need to read the insecticide label and discuss grazing restrictions with their chemical dealer, he said.

Before making any changes in operating plans, producers with crop-insured acres should contact their insurance provider for an appraisal of the crop's value and to request a release of the crop.

If producers graze the corn, it will not be eligible for loan deficiency payments. For more information, contact a local Farm Service Agency.

If the crop is reduced or removed as forage, erosion protection will still need to be maintained. Producers should check with their local Natural Resources Conservation Service office to determine the amount of residue that needs to be left to achieve the level of erosion protection specified in their farm operation plan.

To learn more about some common insecticides registered for use in field corn and/or grain sorghum for grasshopper control visit NU Cooperative Extension's Crop Watch Newsletter Web site. More information on pesticide labels can be found at Greenbook Home.

For more information, contact Hunt at (402)584-2863 or Anderson at (402)472-6237.

07/22/02-SA

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

Tom Hunt - Ph.D.
Entomology
Associate Professor
(402) 584-3863

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

Department: Agronomy & Horticulture|Entomology