Grazing Gold: Effects on Crop Yield

As the availability of nutrients in corn residue declines, producers should adjust feeding management or institute rotational grazing. ( Photo: Sara Brown )

Grazing or bailing corn residue for cattle feed can provide income opportunities, but both processes remove nutrients and organic material from a field, while grazing also recycles some nutrients and organic material in manure. 

Grazing or baling practices could affect subsequent crop-management decisions, and thus influence equitable lease rates for stalk grazing or bale prices. University of Nebraska researchers recently completed a series of studies evaluating the short- and long-term effects these practices have on crop production. 

Researchers conducted a two-year study to evaluate the effects of grazing on subsequent yields and nutrient removal from baling at five locations in Nebraska. 

Their report, titled “Effect of Corn Residue Grazing or Baling on Subsequent Crop Yield and Nutrient Removal,” also is published in the 2017 Nebraska Research Report. 

The researchers compared three treatments on each site: 

visual of three treatments

  • Control corn fields with no grazing or baling
  • Grazing residue, with a target of removing 50% of husk and leaf components, with stocking rates determined using the university’s Corn Stalk Grazing Calculator. 
  • Baling residue following harvest, with bales sampled and analyzed for nutrient content.

Corn and soybean yields varied widely between the research sites, due to weather, soil types and management systems, the researchers note. Yields between treatments at each site however, did not differ significantly. 

The researchers did find a difference in the amount of residue cover following each treatment. Control fields averaged 88.7% cover, grazed fields averaged 77.5% cover and baled fields averaged 45.8% cover. In this test baled fields had a slight numeric yield advantage over control fields. They speculate baling might have resulted in better nitrogen availability in the short term and possibly allowed the soil surface to warm up more quickly in the spring.

The amount of nutrients removed by baling residue varied between sites, but averaged 42 lb. of nitrogen per acre, 60 lb. of calcium expressed as CaCO3 equivalent and 4.3 lb. of phosphorus (P2O3). Potassium (K2O) removal varied widely, from 22 lb. to 285 lb. per acre. 

The researchers conclude that grazing or baling corn residue provides a feed resource without negatively affecting subsequent corn or soybean yields. Baling does, however, remove nutrients, and the amount varies widely. Farmers should weigh and sample bales to create an estimate of nutrient removal and fertilizer requirements in the long term.


Read more in this article series: 

Grazing Gold: A Win-Win

Grazing Gold: Effects on Crop Yield

Grazing Gold: Long-Term Effects

Grazing Gold: 4 Corn Residue Resources

 

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