Erosion and off-site movement of sediment and pesticide contaminants are high priority issues for the wine grape industry.
The Central Coast Vineyard Team (CCVT) is in the midst of several research projects to help growers manage these issues and meet the requirements of the ag discharge waiver. One focus is the search for the ideal cover crop.
“The use of cover crops is one of the most effective ways to manage the runoff of non-point discharges of sediment, nutrients and chemical residues,” says Jill Whitacre, CCVT program coordinator. “But, there is a need for more detailed information regarding the suitability and selection of cover crops in specific areas and specific circumstances.”
CCVT, in cooperation with central coast grape growers, is looking at a number of different cover crops and evaluating their usefulness in commercial production. One of the ongoing trials is being conducted on Halter Ranch, west of Paso Robles.
“We had a test plot that included 20 cover crop varieties planted in November 2005,” Whitacre says. “We took data that included suitability for the soil, climate conditions, and other factors. Six of the 20 cover crops did very well that year, but the winter was very unusual. We had a heat spike in February 2006 that allowed weeds to get ahead of some of the later-germinating cover crop varieties, and then that was followed by two snow events.”
The effort to research ways to protect water quality is ongoing. Last year it was expanded to include a homemade device designed by UCCE San Luis Obispo County Farm Advisor Mark Battany to include measurements on water runoff. But, the 2006-07winter was basically a drought, so runoff was minimal.
“Thirty inches is about normal for the area west of Paso Robles,” Whitacre says. “This past winter we got about 10 inches. It’s always challenging to conduct these trials when nothing is really normal, but we’re getting some useful and interesting data.”
In late June, CCVT received a $75,000 Conservation Innovative Grant (CIG) through USDA’s Natural Resources Conservation Service (NRCS). The funds will be used to help develop market incentives for the increased adoption of conservation practices in wine grapes. The 2002 farm bill established the CIG grants as part of the environmental quality incentives program or EQIP.