KindHarvest summary: Grazing can help a cover crop earn income, but the result depends on residue, stocking rate, soil moisture and timing. A two-year Kansas study compared grazed and ungrazed cover crops on three dryland no-till fields to see whether cattle traffic cancelled the soil benefits.
What the study compared
The trials included winter and summer cover crops in different crop rotations near Marquette and Hays. Cattle grazed for 39 to 55 days at stocking rates between 4.2 and 5.4 animal-unit months per acre. Researchers measured cover-crop biomass and sampled soil before the following soybean or sorghum crop.
Residue recovered after grazing
Grazing reduced cover-crop biomass by about 29%, but regrowth meant the final biomass in grazed plots was similar to the amount present before grazing. Species selection and grazing management left enough residue to continue protecting the soil in these trials.
Measured soil effects were limited
Researchers reported no significant differences between grazed and ungrazed plots in bulk density, aggregate-size distribution, mean aggregate diameter, soil organic matter or pH. Adjacent perennial pasture still performed better on several soil measures, showing that the short field trial did not reproduce the structure of long-established grassland.
Management still determines the result
The findings support careful grazing as one option in a no-till system; they do not mean that grazing intensity is irrelevant. Wet soils, excessive stocking or removing too much cover can increase compaction and reduce protection. Longer-term work across more soils is still needed. KindHarvest also has an overview of the wider benefits of cover crops.
Source and credit
This KindHarvest Team research brief is based on a Kansas State report republished by No-Till Farmer on 6 May 2022. The publisher changed the original article address. Read the full No-Till Farmer article.