Any long-term study of best farming practices will inevitably rediscover an enlightened practice as old as agriculture and as modern as environmental consciousness: the use of cover crops.
Researchers at the Kellogg Biological Station began exploring these time-tested methods early in their comprehensive study, which began in 1988 and continues to this day. A team led by program specialist Dale R. Mutch noted: “Prior to the development of manufactured fertilizers, cover crops were commonly used to improve soil structure and productivity.”
His report advised a wide range of cover crop uses, confirming the benefit, wisdom and ecological value of techniques that are commonly used by veganic farmers:
“Nitrogen management: Cover crops can enhance nitrogen production and/or reduce leaching. Overseed legume (clovers, medic, etc.) cover into corn, frost-seed into wheat, or late summer-seed to provide nitrogen for future crops. Grass (annual ryegrass, cereal rye, wheat, oilseed radish) can be used to take up excess nitrogen and reduce the potential for groundwater leaching.
“Erosion control: Cover crops can be used to reduce wind and water erosion. Maintaining ground cover through fall, winter and early spring drastically reduces soil loss.
“Improving soil quality: Cover crops enhance soil structure while increasing soil biota activity. They reduce soil compaction while increasing water percolation and retention. Cover crops help soils maintain a higher organic matter level than continuous row cropping without cover. They also improve soil aggregation, infiltration and bulk density.
“Weed suppression: Cover crops can play a role in managing weeds by shading and interfering with weed germination and establishment. Cereal rye produces allelochemicals which suppress weeds.
“Insect management: Cover crops will play an important role in future biological insect control. They have increased Trichograma wasp survival for European corn borer control in seed corn.”
As with much of its work, the Kellogg Biological Station focuses on supplying practical guidance to Michigan farmers. The wide range of recommended cover crops in just this one state includes: clovers, oilseed radish, winter wheat, buckwheat, Oriental mustard, cowpea, Austrian winter pea, hairy vetch, sorghum sudangrass and medics.
Medics are an example of the incredible variety of cover crops. There are more than 35 species of this particular legume. Nature has given farmers much to work with, and farm researchers so much to rediscover.