Feeding corn from burnt corn fields

Mary Drewnoski, Beef Systems Specialist

Fire damaged grain, if not completely destroyed, will have an appearance ranging from a slight brownish tint to black. This grain can be salvaged and fed to cattle. Common methods used by commercial labs for evaluation of energy content such as NIR analysis will not provide an accurate estimate of the energy availability from heat damaged corn. However, color can be used as a crude indicator of the relative energy available for cattle. Based on research conducted at Iowa State, the amount of starch from brown and black corn that was digested in the rumen was about 30% less than normal corn. However, this corn would still have a significant amount of energy and can be sued as an energy source. 

The corn in burnt fields can be gleaned through grazing. However, cattle will need to be adapted to corn similar to working cattle on to a finishing diet before turn out or have limited access to avoid acidosis.  Strip grazing is one   Due to the fire removing the residue in the field cattle will need to have a roughage source such as hay provided when grazing.  

Grazing weaned calves on burnt corn fields could be a great way to use this feed resource. It is recommended to have them used to consuming at least 5 lbs of corn before turnout.  In addition to a roughage source these calves will need supplemental protein to make use of the best energy in the corn.  Alfalfa hay could be used as a source of protein and roughage.  Another option would be to provide free-choice grass hay plus 2 lbs of dried distillers.  

Cull cows would be the next best option, as the corn can be used to put on extra weight and increase their value. Before turnout, producers should start feeding grain and work them up to at least 7 to 10 lbs/hd of grain over a week to 10 days.  If you don’t want to feed corn before turn out then strip grazing can be used to adapt the cows to consuming corn. This excel tool can be used to determine how much area to allocate.