Crop residue management

Quick facts

  • Target corn residue harvest in fields that you’ll be planting corn in next year.

  • Rotate residue harvest among fields so you don’t remove residue from the same field every year.

  • Reduce tillage following residue harvest.

  • To add carbon back to the soil, use manure instead of or in addition to commercial fertilizer.

  • Consider winter cover crops. Roots from winter cover crops are extremely effective at scavenging residual soil nitrate and adding carbon to the soil. This is especially important following dry years when uptake of nitrogen by the corn crop is lower than normal.

Most growers incorporate corn residue into the soil with tillage or leave it on the soil surface.

However, some livestock producers harvest corn residue for use as feed and bedding. There’s also interest in using corn residue for biofuel production in order to reduce U.S. reliance on fossil fuels.

However, regularly harvesting all of a field’s corn residue and not returning other sources of carbon to the soil will reduce soil organic carbon and, ultimately, soil productivity.

It’s important to balance short-term economics with long-term sustainability. When removing residue, use common sense to preserve soil organic matter and protect against erosion.

Soil organic matter

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Sustainably harvesting corn residue

The amount of corn residue growers can sustainably harvest without supplemental carbon – such as manure, sewage sludge, perennials or cover crops – depends on the crop rotation and tillage system.

How much residue you can harvest

On average, retain the amount of corn residue shown in Table 1 and Figure 1 to maintain soil organic carbon and protect against water and wind erosion in the Corn Belt.

However, note the amount of corn residue needed to protect against soil erosion is less than the amount needed to maintain soil organic carbon levels.

Table 1 shows the amount of corn residue amount you can harvest for various crop rotations, tillage systems and yield levels – all while maintaining soil organic carbon levels and protecting against water and wind erosion.

Table 1: Maximum amount of corn residue to maintain soil productivity

Corn grain yield Corn residue yield Continuous corn: Moldboard plow Continuous corn: Conservation tillage* Corn-soybean rotation: Moldboard plow Corn-soybean rotation: Conservation tillage
125 bushels per acre 4.4 bales per acre 0 bales per acre 0.5 bales per acre 0 bales per acre 0 bales per acre
150 bushels per acre 5.3 bales per acre 0 bales per acre 1.3 bales per acre 0 bales per acre 0 bales per acre
175 bushels per acre 6.2 bales per acre 0.4 bales per acre 2.2 bales per acre 0 bales per acre 0.2 bales per acre
200 bushels per acre 7 bales per acre 1.3 bales per acre 3.1 bales per acre 0 bales per acre 1.1 bales per acre
225 bushels per acre 7.9 bales per acre 2.2 bales per acre 4 bales per acre 0 bales per acre 2 bales per acre
250 bushels per acre 8.8 bales per acre 3 bales per acre 4.8 bales per acre 0 bales per acre 2.8 bales per acre

*A tillage system with at least 30 percent surface residue coverage after planting.

Table derived from Johnson et al. Notes:

  • Corn grain yield (bushels per acre) reported at 15.5 percent moisture.

  • Residue harvest (bales per acre) across all systems assumes dry residue and 1,200-pound round bales.

  • Residue harvest (bales per acre) across all tillage and rotations assumes no organic inputs, such as manure to the soil.

Factors that affect harvest amounts

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Cost of removing residue

While corn varieties, soil fertility, growing conditions and yield can affect the nutrient value of corn residue, any form of residue removal will remove nutrients from the field.

Eventually, growers would need to replace these nutrients to maintain soil productivity. Corn residue is a source of many nutrients, including nitrogen, phosphorus, potassium, calcium, sulfur, magnesium, copper, manganese and zinc.

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Corn cob removal

Corn cobs are quickly becoming recognized as an important feedstock for ethanol and gasification plants.

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Jodi DeJong-Hughes, Extension educator and Jeff Coulter, Extension agronomist

Reviewed in 2018

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