An innovative University of California sustainable agriculture project that looks at the water-cleansing effects of cover crops under reduced tillage practices has been awarded $90,000 by the Kearney Foundation of Soil Science.

The grant, awarded to the UC Davis Sustainable Agriculture Farming Systems (SAFS) project, will allow researchers to look at the effects of crop debris jams in irrigation furrows when cover crops are planted and allowed to remain in the fields.

"Slowing irrigation water down in the furrows increases the water soil penetration and reduces the amount of runoff that enters streams and rivers," said Will Horwath, one of the project principal investigators and a professor of soil biogeochemistry in the UC Davis land, air and water department. "It's one of the farming practices that has been identified as a sustainable way to prevent nutrients and chemicals from the fields from entering drinking water supplies, and for recharging ground water supplies."

Horwath is the coordinator of the SAFS project, which has looked at reduced tillage, the use of cover crops, drip irrigation and other sustainable farming practices for almost 20 years.

The SAFS main project site is UC Davis' Russell Ranch Sustainable Agriculture Facility, which is also home to the campus Long-Term Research in Agricultural Systems experiment. Both experiments are part of the UC Davis College of Agricultural and Environmental Sciences' Agricultural Sustainability Institute (ASI).

"Results from research funded by the new grant will demonstrate the value of conservation tillage practices in furrow-irrigated agriculture for California farmers," said Horwath. "Concern about leaving residue from reduced tillage on the field is one of the reasons for resistance to the adoption of conservation tillage and other crop residue management practices. We hope results from this work might help resolve some of the questions."

Wes Wallender, a professor in the land, air and water resources department specializing in hydrology and engineering, is co-principal investigator of the project. Post doctoral researcher Damodhara Rao Mailapalli is also working on the project.

Tom Tomich, ASI director, noted that the original SAFS project, which compared conventional, low-input and organic management systems in traditional Central Valley rotations, developed a much clearer understanding of the opportunities for sustainable management. Some of the most important results from the original SAFS project showed how growers can reduce synthetic fertilizer inputs; how to manage cover crops, crop residue and soil organic matter; and how to manage weeds and pests with fewer pesticides, he said. Tomich is also director of the statewide UC Sustainable Agriculture Research and Education Program (UC SAREP), which was the original funder of the SAFS project.

Horwath said the project continues to rely on input from growers and farm advisors as part of the research team. The geographic scope of the project has expanded, with researchers taking measurements at farms in Yolo and Stanislaus counties to identify relationships between management practices and runoff in different areas. In addition to this new grant from the Kearney Foundation of Soil Science, the project receives support from CALFED, the Water Resource Board, California Department of Food and Agriculture and Unilever-Best Foods. The M. Theo Kearney Foundation of Soil Science was created to encourage and support research in the fields of soils, plant nutrition, and water science within the Division of Agriculture and Natural Resources of the University of California. The Kearney Foundation was established in 1951 through an endowment managed by the University of California Board of Regents.