Synergy of Cover Crops with Manure Application

Yield and quality of an oat cover crop was evaluated with and without an application of digestate.  The study was conducted in two years on two separate fields.  The oats were hand harvested and 3 samples were collected for each of the triplicated treatments.  The results were evaluated based on harvested crop value (yield and quality) and how that would compare to potential feed value for milk production, as well as soil organic matter contribution if the crop had not been harvested.

The results show the synergy of feeding the cover crop and the soil microorganisms that enhance nutrient cycling and biomass production. A few highlights shown in Table 1 and Table 2 below.

  • Feed quality decreases (milk/ton) with digestate applied, but yield increases by about 40% to give a 33 to 50% increase in milk production per acre
  • Nutrient uptake is higher than nutrients applied from digestate, indicating increased microbial nutrient cycling
  • The amount of time required to increase soil organic matter by 1% is cut almost in half with the combination of cover crops and organic amendment