Tips for Grazing Standing Corn to Save Feed Costs

By Scout Nelson

Extreme heat stress this year may have reduced corn ear size, causing smaller ears to bounce off combine head during harvest. This can increase yield losses and leave more whole ears on the ground. Cattle may eat these ears whole while grazing cornfields. Although whole ears are generally less concerning than piles of spilled corn, farmers should monitor their quantity and manage grazing carefully to keep cattle safe.

Taylor Grussing, SDSU Extension Cow/Calf Field Specialist, and Kim Ricardo shared practical guidance on managing standing corn for cattle grazing. Their recommendations cover feed planning, daily grazing areas, cattle diet changes, fencing, and safety measures that help farmers reduce costs while meeting livestock needs.

Planning Grazing on Standing Corn

Doug Sieck, a cattle producer from the Selby, South Dakota, area, recommends leaving 30 rows of standing corn and harvesting a pass of 6 or 12 rows to estimate yield potential. This information helps producers determine how much grain and crop residue they can allocate to cattle for a planned grazing period.

As a general guide, Sieck recommends providing about 10 pounds of corn and 10 pounds of corn residue per cow per day. This amount can meet the energy needs of a midgestation cow, but it may not satisfy the animal's total daily dry matter intake.

Before cattle enter a standing cornfield, producers should gradually adjust their diets to help prevent digestive problems. A suggested approach begins with 3 to 4 pounds of corn per head per day, followed by increases of 2 pounds per head each day until cattle reach the target of 10 pounds per head per day.

Farmers can estimate available crop residue using approximately 50 pounds of corn residue per bushel harvested. Even with this approach, cattle may require additional feed because the suggested grain and residue allocation may not meet the daily dry matter intake target of 2.5 percent of body weight. Supplemental protein, such as alfalfa or cake, can be provided twice a week to help balance nutrient needs.

Good fencing and cattle trained to respect electric fences are important for successful grazing. Jim Gerrish recommends ‘putting up tomorrow’s fence today’ as a backup plan in case cattle leave their assigned grazing area.

Creating Grazing Allotments

Temporary fencing allows farmers to control how much feed cattle access each day. Allotments should reflect crop yield, herd size, and expected intake. Farmers should watch body condition and adjust grazing areas or move cattle more often if feed supplies are lower than expected.

For example, a field producing 50 bushels of corn per acre contains about 2,800 pounds of grain per acre, based on 56 pounds per bushel. At 75% grazing efficiency, about 2,100 pounds of grain per acre are available for cattle.

For a herd of 100 cows eating 10 pounds of grain per day, the calculation is:

• 100 cows × 10 pounds = 1,000 pounds of grain needed daily.
• 1,000 pounds ÷ 2,100 pounds per acre = about 0.48 acres per day.

Farmers may choose to set up one-acre grazing areas for two days instead of moving fences daily. This can reduce labor while still controlling feed access.

Managing Costs and Cattle Safety

Grazing standing corn can reduce the need to harvest, haul, and store grain. Producer Doug Sieck, from the Selby, South Dakota, area, estimates that grazing costs about $0.75 per cow per day on his operation, compared with roughly $4 per head per day in a feedyard. Actual savings vary with local costs and management.

Good fencing and trained cattle are essential. As Jim Gerrish recommends, ‘putting up tomorrow’s fence today’ provides a backup if cattle leave their assigned grazing area.

Best Practices for Successful Grazing

Farmers should provide clean water, suitable mineral support, and protection from winter winds. Corn should be tested for nitrates, and an ionophore may be used when advised by a veterinarian or nutrition expert. A backup feeding area is also important when weather or field conditions prevent grazing.

With careful feed planning, gradual diet changes, regular monitoring, and secure fencing, standing corn can help farmers manage feed costs and make better use of available crop resources.

For more guidance, listen to the Cattle HQ Podcast, Are You Harvesting Your Corn the Correct Way? Tips to Graze Standing Corn, available through SDSU Extension.

Photo Credit: gettyimages-chrisboswell