BIFS Workgroup focuses on partnerships, nitrogen, project evaluation

"Grower Participation in Agricultural Partnerships" was the lead session for the Biologically Integrated Farming Systems (BIFS) Workgroup plenary meeting on October 1, 2002 at UC Davis. Each year, the workgroup meets to discuss current issues in the science of sustainable agriculture and discuss potential workgroup projects to further the goals of BIFS and BIFS-like programs. Workgroup attendees totaled 42 participants, representing 10 academic departments at three UC campuses, farm advisors from eight counties, and over 20 other federal and state program administrators, private foundations, commodity representatives, pest control advisers (PCAs), and farmers.

Social Science of Partnerships

The first session was led by UC Santa Cruz doctoral student Keith Warner, whose work is supported by a BIFS Workgroup research project directed by principal investigators Margaret Fitzsimmons of the UC Santa Cruz environmental studies department, SAREP Associate Director Jenny Broome and Christy Getz, a UC Berkeley Cooperative Extension specialist in natural resource dependent communities. He based his talk on his doctoral thesis "Agroecology in Action: Nature, Networks, Knowledge and Risk in California Agriculture," and focused on questions of agricultural partnerships-how they work, how they influence pest management decision-making processes, the role of growers in partnerships, and the role PCAs play in decision-making.

Warner defined a partnership as "an intentional network of relationships." A social scientist, he suggested an alternative approach for agricultural extension based on partnerships that support a "knowledge system" taking all actors into account, allowing collaboration. He said this differs from the traditional agriculture model, which assumes that growers, researchers, extension specialists and PCAs are separate entities and develop their expertise in isolation. This model sees farmers as "users," with technology and information being "delivered" to them, while a partnership model strives to legitimize grower knowledge of his/her agroecosystem, incorporating that knowledge into research and extension activities.

A partnership strategy has many advantages for agriculture as well as for growers. Warner believes that, "the partnerships with the greatest impact have been able to persuade growers to accept a more complex definition of risk, one that integrates economic, agroecological and environmental factors, worker safety factors, regulatory pressures and public perceptions of agriculture."

Nitrogen Panel

The second session was a panel presentation on nitrogen (N) management in orchards, row crops and dairy operations. Marco Barzman, former SAREP BIFS coordinator, presented an overview of the literature on off-site movement of nitrogen and its environmental and health effects. Stu Pettygrove, of the UC Davis land, air and water resources department presented "The Problem with Bessie," a look at the management of dairy manure and nitrogen in a long-term BIFS project with the dairy and forage crops industry. Pettygrove's project involves reducing the use of commercial fertilizers by using lagoon water (liquid manure) in measured quantities as fertilizers on forage crops. Pettygrove emphasized the need to look at the whole farm system-all inputs and outputs-before being able to accurately analyze nitrogen use.

Will Horwath, also of the UC Davis land, air and water resources department, and Alison Berry, UC Davis environmental horticulture department, spoke on the use of cover crops in managing fertility in row crops and orchard crops. Horwath focused on the effects of cover crops on soil nutrients, and described a study in which he compared conventional rotations to organic and low input systems. Indications are that cover crops not only add nitrogen (N) to the soil, but can capture N that is already in the soil, making it more available for use by crops. This appears to also increase yield if the cover crops are managed properly.

Berry's presentation affirmed these ideas. Legumes as cover crops are nitrogen fixers. They do not merely cycle, but contribute a net input to the soil. Her studies have shown that the no-till management of leguminous cover crops in sprinkler-irrigated orchards leads to rapid breakdown of mowed vetch residue and that the majority of the nitrogen is released in the first four weeks. Prompt N uptake by young almond trees was also demonstrated. Her lab is conducting similar work on winegrape vineyards.

The nitrogen panel concluded with a discussion of the adoption rates of
new techniques for managing N inputs by Mark Cady, program director of Community Alliance with Family Farmers (CAFF). He described a nitrogen budgeting worksheet for almond and walnut growers to calculate optimal fertilization rates. Patrick H. Brown, of the UC Davis pomology department, developed the nitrogen fertilization model on which the worksheet is based with funding from the California Department of Food and Agriculture's Fertilizer Research and Education Program and SAREP. Online interactive versions of the nitrogen model are available for almonds and walnuts at:

• http://fruitsandnuts.ucdavis.edu/almond/html/almond_n_model.html
• http://fruitsandnuts.ucdavis.edu/walnutnmodel/html/walnut_n_model.html

While this nitrogen budgeting tool has been made very easy to use, there is still a problem with growers actually putting it to use, Cady said. He also noted that many growers define cover crops in different ways so it is difficult to get an accurate picture of actual practices in the field.

Project Impact Assessment

The meeting concluded with a session on impact assessment. Joe Grant, UC Cooperative Extension farm advisor for San Joaquin County, and Bev Ransom, BIFS coordinator, presented the results of an extensive survey of walnut growers in San Joaquin County. The purpose of the survey was to get a picture of the practices walnut growers use in alternative and conventional systems. (See "Walnut BIFS project: San Joaquin County Walnut Growers Survey," page 4 for an account of the survey and its results.)

Kris O'Connor and Craig Macmillan of the Central Coast Vineyard Team winegrape BIFS project demonstrated their database system, as did Gary Obenauf and Jed Walton of the Integrated Prune Farming Practices BIFS project. These databases are designed to help growers keep records of many aspects of their farming system, including pesticide and fertilizer inputs, irrigation schedules, pest and beneficial organism monitoring data and more. Minghua Zhang, of the UC Davis land, air and water resources department, presented her GIS database containing the California Department of Pesticide Regulation's pesticide use data, and a poster of her recent analysis of the San Joaquin County walnut Biologically Integrated Orchard Systems (BIOS) project's pesticide use trends.

To be added to the BIFS Workgroup listserv, send an email to bifs@ucdavis.edu. To view notes of workgroup discussions, visit the BIFS Workgroup section of SAREP's Web site at www.sarep.ucdavis.edu/BIFS/workgroup.htm.