Challenging times for California farmers

As if native weeds, diseases and insects weren't enough, California farmers seem to be facing ever increasing numbers of imported pests from far flung corners of the globe.

That fact prompted the Napa Valley Register to run a story about "Moth wars" which detailed battles underway to combat light brown apple moth, a pest from Australia, and European grapevine moth, an Italian native that has caused serious grapevine damage in Uzbekistan and Azerbaijan.

The European grapevine moth "snuck in under the radar" about the same time agricultural officials were beginning releases of sterile light brown apple moth, the story said. For three years, officials have been trying keep the light brown apple moth from becoming permanently established in California.

They have tried spraying in Santa Cruz County and placed pheromone traps in various cites. In the Carneros region, agricultural officials began releasing sterile male and female apple moths to prevent mating and eradicate the population.

“This is an approach that has never been tried before on this moth that feeds on many different types of plants and over such a large geographic range,” the story quoted UC Cooperative Extension integrated pest management advisor Lucia Varela. Information from the UC integrated pest management program on light brown apple moth and European grapevine moth are posted on the IPM Web site.

About the same time the sterile moths were released in Carneros, new mating populations of light brown apple moth were found in Manteca, Calif., according to the Manteca Bulletin. Manteca, about 80 miles east of San Francisco, is a rural, traditionally agricultural area that has become a bedroom community for Bay Area commuters.

The story, written by the newspaper's managing editor Dennis Wyatt, said  CDFA is establishing quarantine areas in two Manteca neighborhoods. They will be attaching "twist-tie" pheromone dispensers on trees in front and back yards. The infusion of pheromones will confuse male moths, making it difficult for them to find females to mate.

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