A San Mateo County Department of Agriculture pest detection specialist discovered three male gypsy moths recently near a residence on Minoca Road in Portola Valley.
Gypsy moths pose a serious threat to trees and shrubs, often times feeding on oak, pine, eucalyptus, manzanita and redwood trees, county officials reported.
A single gypsy moth caterpillar can defoliate up to a square foot of leaves in one day, according to officials. And, when present in large numbers, the caterpillars can defoliate thousands of acres of trees in one season.
Though gypsy moths are more commonly found in the eastern United States, they often “hitchhike” into California by way of vehicles, officials reported.
To monitor the presence of gypsy moths in San Mateo County, pest detection specialists will place survey traps around the residence where the moths were found on July 25.
Traps will continue to be monitored in Portola Valley through September, said Maria Mastrangelo, the county’s deputy agricultural commissioner.
Portola Valley residents with questions about the gypsy moth are invited to contact the San Mateo County Department of Agriculture at 363-4700.
According to the county, if gypsy moth egg masses are found, a cooperative eradication program with the California Department of Food and Agriculture will likely take place. Such an eradication program, though, would not take place until next year.
In 1999, three gypsy moths were found in Woodside and one was found in Montara. In 2000, a single gypsy moth was found in Woodside, officials reported.
The 1999 and 2000 Woodside finds were in the vicinity of Whiskey Hill Road and Mountain Home Road. Additional detection traps were placed and serviced from 1999 through 2001 and no additional gypsy moths were found.
The recent Portola Valley find is more than six miles from the Woodside sites and is not considered to be related.
— Bay City News
