Purdue extension specialist provides tips on what to consider
Farmers with drought-damaged corn in the U.S. might be able to turn it into animal feed to get back some of its value, which would also help livestock owners supplement low forage supplies, according to Keith Johnson, a forage specialist at Purdue University Extension.
The damaged corn could be harvested as either whole-plant silage or green chop. “Feeding value of drought-stressed corn is influenced by several factors, but in general is higher than expected,” said Johnson. “Most studies indicate feed value of drought-stressed corn to be 80–100 percent that of normal silage.” Purdue University studies showed little or no difference in feedlot gain or milk production when beef and dairy cattle were fed normal or stressed corn silage, said Johnson, but as a rule drought-stressed corn will have slightly more fiber, less energy and 1 percent to 2 percent more protein than normal silage.
Moisture content of the crop is important when trying to get the most money out of it, said Johnson. “Ideally, the crop should contain 60–70 percent moisture at harvest,” he said. “For upright silos, to avoid seepage, growers should harvest at 60–65 percent, whereas for bunker silos, harvesting at 65–70 percent moisture will result in better packing and storage qualities.” He said producers tend to harvest the damaged crop too soon, meaning silage has too much moisture, which can result in poor fermentation and lower feed value.
Nitrate is also a concern, and Johnson said livestock producers need to make sure they have their feed tested for it as nitrate levels can be higher in drought-damaged corn. While the potential for nitrate toxicity after fermentation is reduced, Johnson said it’s still a good idea to have the feed analyzed. Johnson said that herbicides and insecticides applied to the corn crop have feeding restrictions, and growers should watch labels and be in touch with chemical suppliers to make sure the crop is harvested and fed safely.