August 26, 2004
What To Do With Immature Corn
Some producers may be faced with the necessity of using their corn crops for hay, grazing, or silage because of the cool weather or frost damage, or to supplement poor grazing conditions because of drought.
"One of the major concerns with corn in drought areas is the level of nitrates," says Greg Lardy, a North Dakota State University beef specialist. “Whether haying or ensiling corn, the producer needs to cut the stalks higher off the ground. Nitrates accumulate in the lower portion of the corn stalk. Ideally, wrapping or bagging the bales to produce bale silage will help the process of fermentation start and lower the concentration of nitrates in the hay. Ensiling whole corn plants can be difficult due to the challenges in getting adequate oxygen exclusion necessary for proper fermentation. Nitrate levels will not decrease in corn hay as they will in silage. Whether or not you put up drought-stressed corn as hay or silage, it’s a good policy to have nitrate levels tested.
"Check the labels of any herbicide you have been using, and make sure that it is labeled for haying," Lardy says. Moisture level in corn hay is also a concern. "To store the corn as hay, you want a moisture level of about 15 to 18 percent or less."
If the drought-stressed crop is going to be hayed, the sooner the producer harvests it, the better, according to Lardy. "We are talking about what is basically a coarse grass," he says. "The hay must be mechanically processed or crimped to help facilitate field curing, and should be cured about seven to 10 days to cure effectively. Baling can also be a challenge with corn. In some cases, large square bales may work the best. Previous producer experience with baling corn indicates it can be very difficult. Spontaneous combustion can be a danger with poor dry down and excessive moisture. In addition, mold development can also occur which will lower the feeding value of the hay and potentially cause other feeding problems. Haying may work in areas with drought-stressed corn. In areas where corn height is near normal, the volume of material which would need to dry down in the windrow may prevent effective use of hay. In these cases, grazing or silaging immature corn may be the only options.
"The level of nutrients in the hay will decrease with maturation," Lardy says. "Along with nitrate levels, it would be a good idea to test for nutrient composition as well. Drought-stressed corn hay will provide nutrient quality comparable to a medium to poor quality forage. Immature corn silage will have a higher crude protein content and a lower energy content than normal corn silage. In addition, immature corn will have greater levels of moisture making ensiling more challenging."
Nitrate-containing feeds should be introduced slowly into rations, according to Lardy. Nitrate poisoning symptoms include increased pulse rate; heavy, quickened breathing; muscle tremors; weakness; staggered gait; blue mucous membranes and blindness. Should any of these symptoms occur, remove the animals from the feed and contact your veterinarian.
For more information, go to http://agbiopubs.sdstate.edu/articles/ExEx4017.pdf.