Crowding and shading out weeds with the cover crops, reducing the need for expensive herbicides. Reducing the need for irrigation water. Cutting fuel costs and soil compaction. Dick and several OSU graduate students and colleagues are collaborating with some of the same farmers. On one half they use conventional tillage.
Crops grow in the summer, there's some tillage in the fall and the land sits bare in the winter.
On the other half of their fields the farmers use self-designed reduced tillage systems in combination with winter cover crops. Cover crops capture residual fertilizers in the fall to maintain groundwater quality and add organic matter that provides 'glue' for soils to create more air spaces and improve water penetration and storage. Sustainable agriculture experimentation has also reached Oregon's wine industry. We do allow the use of chemicals but they are restricted. No applications of broad spectrum herbicides or pesticides.