January 2000
Biological Apple Farming Reduces Risks to Urban Areas
Rapid urbanization around Contra Costa County apple and pear orchards and resulting concerns about the pesticides used in crop production has inspired a farm advisor to organize a project to help growers reduce pesticide use.
"Apples are the highest value agricultural crop in Contra Costa County," says Janet Caprile, UC Cooperative Extension farm advisor. "Most are grown in the eastern portion of the county surrounding the cities of Brentwood, Oakley and Byron, which are among the fastest growing cities in the state." Small numbers of pears, a closely related pome fruit with similar pest management problems, are grown in the same area.
Caprile is the principal investigator of a newly funded Biologically Integrated Farming Systems (BIFS) project, which is focusing on reducing the use of controversial, broad-spectrum insecticides in pome fruits (apples and pears). BIFS is administered by the Davis-based UC Sustainable Agriculture Research and Education Program (SAREP). A key component of the newest BIFS project is the use of mating disruption (MD) to reduce the numbers of codling moth, the most critical pest in apple and pear production. If left unchecked, codling moths larvae, the proverbial "worm in the apple," can cause more than 80 percent fruit loss. Typically, control strategies for codling moths rely on organophosphate sprays, which can lead to outbreaks of secondary pests (mites, leafhoppers, aphids).
"An alternative approach to codling moth management is central to the transition away from the disruptive pesticide treadmill," Caprile says.
During the first year of the three-year BIFS project, Caprile and a team of growers, pest control advisors and UC researchers will be using supplemental codling moth sprays in addition to MD to reduce codling moth populations to very low levels.
"As pest pressure decreases, the supplemental sprays will shift from the more toxic and broad spectrum organophosphates to less disruptive, low toxicity but less effective materials," she says. "Once the organophosphates have been eliminated form the system, releases of recently imported codling moth parasites will be made to supplement mating disruption. As the codling moth pressure continues to decrease, the MD per acre can be reduced to lower pest management costs."
She notes that as the disruptive sprays for codling moth are reduced, many of the secondary pests have the potential to be adequately controlled by fertility and water management, and biological methods.
Caprile says the primary barrier to adoption of MD in California previously has been cost. That’s where the BIFS program comes in. To offset the increased cost of a MD program, BIFS will offer a 50 percent cost share for the mating disruption product to participating growers for the first three years. This would make California grower costs equal to those for Northwest growers, who have shorter seasons and lower pest pressure.
The apple-pear BIFS project will receive a total of $140,000 for the next three years, according to Max Stevenson of SAREP, coordinator of the BIFS grants.
"I grew up in Contra Costa County and the rate of urbanization is truly amazing," Stevenson notes. "If agriculture is to continue in the county, farming will have to improve the quality of life for urban neighbors, not degrade it. Reduced pesticide use in the apple BIFS project goes a long way in that regard.
Media Contacts:
Lyra Halprin, (530) 752-8664, lhalprin@ucdavis.edu
