College News

Ag Instructor Vic Martin: What to do with Crop Residue

Great Bend Tribune
Published November 21, 2021

As of November 16th drought conditions are essentially unchanged for the state and the cooler conditions should keep it that way.  The six to ten-day outlook (November 24 to 28) indicates we are on the line between normal and slightly above normal temperatures and normal to below normal precipitation. The eight to fourteen-day outlook (November 26 to December 2) indicates we have a 40 to 50% chance of above normal temperatures and a 33 to 40% chance of below normal precipitation.  Currently, input prices are considerably higher for crop and livestock producers while commodity prices while higher than a year ago are lower than recent highs for crops.  While prices for beef in stores is much higher than a year ago, from cow-calf to stocker and fed cattle and finally finished cattle aren’t great.  To make this work cattle producers need to find ways to be more efficient (decrease input costs) so they can work towards profitability.  Before heading to the feedlot, producers use several techniques.  One common method is winter cereal grazing (wheat, barley, rye, triticale).  Another common technique is grazing stalks from corn and grain sorghum.  Occasionally, a combination of these two methods are employed.  The upshot is that this can minimize supplemental feeding and decrease costs while producing desired gain and outcomes.  Today, what are the considerations in grazing corn and grain sorghum (milo).

  • This was especially common prior to Bt corn as a way to take advantage of dropped ears and grain on the ground it presented challenges to cattle health.  Typically, today there is much less due to improved technology and Bt corn.
  • While the nutritional value of corn and sorghum stalks is similar, sorghum stalks are normally more digestible.  Corn husks have more energy as they possess less lignin than stalks.
  • A benefit of grazing stalks is eliminating heavy residue cover, especially under irrigated conditions without tillage.  Care should be taken to leave around 40 to 50% of the residue to protect the soil.  The length of time for effective grazing is a function of grain yield and animal weight.  Lactating cattle will naturally consume more.
  • Cattle will selectively graze more palatable plant parts, grain followed by husks and leaves.  Stalks are the least palatable.  The quality is also affected by wet weather and trampling. 
  • A very desirable grazing system if feasible is having winter cereal pasture and stalks adjacent to each other.  Cattle really need to only be on winter cereal pasture a few hours a day to optimize gain and can spend the rest of time on crop residue.  This potentially allows for a heavier stocking rate on the winter cereal.  This system does take more time and management.
  • Two caveats are in order.  Depending on soil conditions, cattle can compact and tear up the soil, especially the top several inches and may take some tillage to fix.  And for sorghum, while normally not a problem – check for nitrates.  Finally, a producer must be ready to supplement as dictated.