Aerial pheromone treatments planned to begin in late spring or early summer
SACRAMENTO – The California Department of Food and Agriculture (CDFA) and the United States Department of Agriculture (USDA) continue to develop their plans for the 2008 Light Brown Apple Moth eradication program in nine Central California counties along the coast and in the Bay Area.
In planning the eradication program, CDFA and USDA are working with a team of international Light Brown Apple Moth experts that believes the pest can be eradicated through the primary use of aerial pheromone treatments along with other techniques. A pheromone is a natural scent that an insect produces to communicate with a potential mate. Pheromone use for this pest works by confusing the male moth, which disrupts the mating cycle, thereby decreasing or eradicating the pest population. Pheromones are not harmful to people, pets or plants.
Specific plans for communities within the nine-county region are still under consideration and are dependent on variables including moth detections and funding as the program moves forward.
The CDFA/USDA approach continues a long-standing policy of using the most environmentally sensitive yet effective tools in eradication programs. All of the techniques being considered are alternatives to widespread spraying of conventional pesticides.
Aerial pheromone treatments are planned to begin in late spring or early summer. The USDA is currently field testing a number of new aerial pheromone products in New Zealand, with the goal of finding a pheromone product that lasts longer in the environment than 30 days, therefore requiring fewer aerial treatments. Both the USDA and CDFA feel this is important in light of community concerns about the frequency of treatments. The products used in aerial treatments last year, Checkmate OLR-F and Checkmate LBAM-F, were designed to last 30 days in the environment.
While research in New Zealand continues, it is critical that ground treatments resume soon. Pheromone treatments with twist ties will likely begin in February, on a date yet to be determined. Twist ties are applied by ground crews to host plants, trees and fence posts in isolated, lightly infested areas within the nine-county region. This approach creates mating disruption by dispersing moth pheromone in the infested area.
Ground treatments with Bt (Bacillus thuringiensis), a naturally-occurring bacteria, and spinosad, an extract from naturally-occurring bacteria, may be utilized in heavily infested areas where moth larvae have been detected. The formulations of each product that would be used are approved for use on organic crops. No specific treatments with these products have been scheduled. This approach is intended to complement and not replace aerial pheromone treatments.
The USDA and CDFA are also evaluating another method - a male attractant treatment. This would start in the most densely infested areas and would consist of a ground treatment featuring pheromone mixed with a small amount of pesticide that would attract and then kill male apple moths. The mixture would be applied out of reach, at a height of approximately eight feet, on utility poles and trees. The pesticide that would be utilized is permethrin, a common household product that is used frequently for flea control on family pets. While no specific treatment using this method has been scheduled yet, it may be used in the period when aerial pheromone products are being tested. Again, this approach is intended to complement and not replace aerial pheromone treatment.
Additionally, the two agencies may introduce Trichogramma wasps, which are tiny and stingless, to help with eradication. The wasps lay their eggs inside moth eggs. The wasp larvae hatch and eat the host egg from the inside. These wasps will not bother over-wintering monarch butterflies and they would not be released near threatened or endangered plants or butterflies and moths.
The first confirmation of the Light Brown Apple Moth in the Bay Area came in February 2007. Since then, many thousands have been detected throughout the central coast region, in the counties of Monterey, Santa Cruz, Santa Clara, San Mateo, Contra Costa, Marin, San Francisco, Alameda and Solano. Small, isolated infestations detected last year in Los Angeles and Napa counties have already been eradicated.
The Light Brown Apple Moth is native to Australia and is found in New Zealand, the United Kingdom and Hawaii. The range of host plants is broad with more than two-thousand plant species known to be susceptible to attack by this pest. It threatens California’s environment—including cypress, redwood and oak trees—and the food supply. The pest destroys, stunts or deforms young seedlings; spoils the appearance of ornamental plants; and injures citrus, grapes, and deciduous fruit tree crops.
California Department of Food and Agriculture Office of Public Affairs
1220 N St., Ste. 214, Sacramento, CA 95814