June 4, 2004
Conservation tillage comparison emerges from 16-year study of sustainable farming practices
Soil sampling at UC Davis conservation tillage and cover cropping research site.
DAVIS -- A new location and
purpose for a successful 16-year-old farming comparison project at UC Davis will
be revealed at a field day June 24. The study of alternative practices, which
has helped change the way Sacramento Valley farmers grow field crops, has
evolved into a farming systems experiment focused on conservation
Charles "Chuck" Ahlem, the undersecretary of agriculture
for the California Department of Food and Agriculture, will be the field day
keynote speaker. State Secretary of Agriculture A.G. Kawamura is an invited
guest at the event, which will take place at UC Davis' Russell Ranch, seven
miles west of the main campus.
The project's new permanent site is
also home to the UCD College of Agricultural and Environmental Sciences'
Long-Term Research in Agricultural Systems experiment.
experiments are part of the college's emerging sustainable agriculture and
natural resource program," said William Horwath, the project leader and UC Davis
professor of land, air and water resources.
emphasizing conservation or reduced tillage, and the use of non-cash cover crops
to improve soil and water quality in typical California cropping systems," said
Horwath. More than 20 faculty, Cooperative Extension researchers and growers are
participating in experiments at the site. Participants are working with UC's
statewide Sustainable Agriculture Research and Education Program (SAREP) on
Some of the most important results from the original
Sustainable Agriculture Farming Systems project showed where 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, Horwath
said. The project, which began in 1988 with funding from SAREP, developed a much
clearer understanding of the economic opportunities and limitations of organic
"The new project has a different focus," Horwath
said. "Now we're studying the effects of conservation tillage and cover cropping
on the way sediment, nutrients and pesticides are transported off conventional,
cover-cropped and organic farming systems."
"We're also looking at
the tradeoff between ecological benefits and economic costs in a sustainable
system," he said. "And, it is vital that we share our results with farmers and
the broader agricultural community."
Horwath said the project
continues to rely on input from the growers and farm advisors on 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. A CALFED grant is
funding a major portion of the work, with additional support from the California
Department of Food and Agriculture and Unilever Bestfoods.
In addition to the main plots at the Russell Ranch, the project
includes a 14-acre area for companion studies designed to refine management
practices for successful use of conservation tillage and cover cropping in Yolo
The SAFS field day gets underway with a 7:30
a.m. sign-in. Undersecretary Ahlem's keynote begins at 8 a.m. Participants will
board tractor-drawn hay wagons to tour the research site at 8:30 a.m. At four
sites, researchers will discuss water management and conservation in cover
crop-based cropping systems; conservation tillage in tomato and corn production;
weeds in furrow, drip and sprinkler irrigation system comparisons; and soil
fertility and plant nutrition. After lunch, participants will hear updated
information on the economic impact of conservation tillage. The final event of
the day is a grower panel discussion, which has become a favorite for growers,
pest control advisers and certified crop advisers interested in farmers'
perspectives on the research results presented. The field day is scheduled to
adjourn at 2:30 p.m.
Pre-registration is requested by June 18. The
$10 fee ($5 for students) will cover the cost of lunch and refreshments. PCA and
CCA Continuing Education units are pending.
directions are on the Web at
The site is located
seven miles west of the main UC Davis campus on Russell Blvd., 1/2 mile west of
County Road 95. For more information, contact Sam Prentice at (530) 752-2023 or