Submitted to: National Conservation Tillage Digest
Publication Type: Popular Publication
Publication Acceptance Date: July 1, 1998
Publication Date: N/A
One of the primary reasons for using conservation tillage practices is to decrease runoff in order to reduce soil and chemical losses. In particular, no-till has proven to be very effective in drastically reducing runoff from some soils. No-till also results in a more favorable environment for earthworms and their populations can be much greater in no-till than in tilled fields. Although the burrows constructed by these earthworms may help to reduce runoff from no-till soil, there is concern that they may also contribute to chemical contamination of groundwater. Our research indicates that earthworm burrowing activity has only a small effect on chemical transport to groundwater, even under extreme circumstances, such as heavy rainfall shortly after the surface application of agrochemicals. Earthworm burrows can have a much larger effect on reducing runoff, which is oftentimes a greater concern and a more significant source of water contamination. Moreover, there are other benefits associated with maintaining thriving earthworm populations in agricultural fields. These include improved soil aggregation, burying and mixing of residue, and more efficient cycling of nutrients.