Officials Step Up Search for Gypsy Moths at 5 Sites

Recent discoveries of gypsy moths have prompted stepped-up monitoring for the voracious leaf-eating insects in five areas of the San Fernando, Santa Clarita and Conejo valleys, but so far there are no indications of a general infestation, state and county agricultural officials said Thursday.

The capture Aug. 4 of a single moth on Remick Avenue in Sun Valley prompted state agriculture officials to set out 100 additional traps in a four-square-mile area around the find.

Extra traps were installed in Chatsworth and Newhall two weeks ago and in Thousand Oaks and Woodland Hills earlier this summer after single male moths were captured in each of those locations.

But with no additional moths yet captured at any of the sites, “I’d say it looks very hopeful,” said Jim Wiseman, supervising agricultural inspector with the Los Angeles County agricultural commissioner’s office. “Usually, if there were an infestation, one would find additional male moths within a short period of time . . . probably within a matter of days.”

Locally, the last gypsy moth infestation occurred in Encino in 1987 when chemical and bacterial pesticides were used to kill young gypsy moth caterpillars.

Gypsy moths, native to Europe, were inadvertently introduced into the eastern United States, and are brought here from the East on recreational vehicles, swing sets, picnic tables and similar outdoor articles.

“They’re not particularly fussy about where they go into the cocoon stage or where the female lays her eggs, and she may lay her eggs on a rock . . . or the wheel of a lawn mower or the side of a doghouse,” Wiseman said.

“So, when people from the East move here and bring these outdoor items with them, they may be carrying gypsy moth egg masses,” he said.

Don Henry, chief of the pest detection-emergency projects branch of the state Department of Food and Agriculture, said the local moths are among 53 that were captured statewide this spring and summer. He said some chemical treatment will be used in an area of Marin County, where 18 of the moths have been found.

County agriculture officials routinely maintain three gypsy moth traps per square mile. The traps are baited with a sexual pheromone exuded by female moths.

100 Traps in Area

When a male moth is caught, the state Department of Food and Agriculture blankets the area with 100 traps--installing 25 traps per square mile in the four square miles surrounding the find.

Before the Sun Valley capture, single male moths were found the last week of July near Devonshire Street and Valley Circle Boulevard in Chatsworth and near San Fernando Road and Lyons Avenue in Newhall.

Once in June and again in July, single moths were trapped in Thousand Oaks, officials said. Also in June, a moth was caught in Woodland Hills near the intersection of Mulholland Drive and Old Topanga Canyon Road.