In parts of Eastern Canada, cool wet springs seem to be becoming the norm. As a result, farmers can’t get onto their fields early in the spring, particularly if they have heavy clay soils. For no-till farmers, the problem is even worse. Overwintered cover crops, depending on how they are managed, may help with this problem by taking up moisture from the soil.
Researchers in Pennsylvania compared two approaches to no-till growing of corn and soybeans. The more common method is to ‘terminate’ a cover crop using herbicides and plant a couple weeks later. The approach under investigation involved letting the cover crop grow, planting crops into the living cover crop and then killing the cover crop a week later. This approach helped dry out the soil. Also, the extra three weeks of growth provided extra biomass that protected the soil and conserved soil moisture throughout the summer. This did, however, reduce soil temperatures and the corn yield was slightly lower as a result (but the soybean yield wasn’t affected).
The researchers had hypothesized that the living cover crop might reduce slug damage by providing an alternative food source for the slugs. However, the effect of the cover crop on slug damage was inconclusive as it varied between years, crops, fields and types of cover crops.
Source: Reed, Heidi K., Heather D. Karsten, William S. Curran, John F. Tooker, Sjoerd W. Duiker. 2019. Planting Green Effects on Corn and Soybean Production. Agronomy Journal. Volume 111, Issue 5, pp. 1-12.