WASPS TO BATTLE TREE-KILLING BUGS.

Byline: Erik Nelson Staff Writer

NORTH HOLLYWOOD - Eucalyptus sap-sucking psyllids, beware.

Today, for the first time in California, parasitic Australian wasps will be released in North Hollywood to hunt down and eat the red gum lerp psyllid, which has been attacking eucalyptus trees across the state since 1998.

At 9 a.m., 100 males and 100 females will be released on 20 trees in Valley Village Park. The tiny wasps are said to be harmless to people and everything but the psyllids, which infect trees and secrete a sticky substance that messes up cars and sidewalks.

``We have very high hopes that this is going to take care of it,'' said Los Angeles Agricultural Commissioner Cato Fiksdal, whose agency provided infested eucalyptus trees to help test the wasps before their release.

``We've had releases like this of other parasites for pests in the past and they've worked quite well.''

For six months, biological control expert Don Dahlsten has been breeding parasitic Australian wasps known as psyllaepagus at the University of California at Berkeley's Center for Biological Control.

After watching them lay their eggs inside the larval psyllids and seeing the wasp larvae eat the psyllids from the inside out, Dahlsten decided it was time to try them in Southern California.

After the initial group lays eggs, it should take about two weeks for the first brood to mature if their laboratory, or ``insectory'' behavior continues, said Gerry Pennere, supervisor of city Recreation and Parks Forestry Division.

``It's not going to be an instant cure,'' Pennere said. ``It could be several weeks to several months, depending on how fast they start reproducing and how successful the program is.''

An initial psyllid control program tried in May 1999 in Valley Village park was only partially successful. Authorities released 2,000 ladybugs, which obediently ate the psyllids, but cleared out after about two weeks, Pennere said.

The park actually has several insects that eat the psyllids, including the minute pirate bug, the green lacewing and the syrphid fly. These failed to make a dent in the psyllid population, however.

It might take an Australian import, the wasp, to kill an Australian pest attacking another Australian import, the eucalyptus, which has been around for about a century in California.

Laurie Dinkin, president of the Valley Village Homeowners Association, said she began noticing the eucalyptus blight about a year and a half ago.

``I saw suddenly that there were a lot of leaves on the ground, and they were all curled up with a sticky substance,'' she said. ``I just hope they can save those beautiful trees, as long as (the wasps) are not dangerous to anybody, that they don't sting or anything.''

That substance is honeydew that the psyllid offspring, called nymphs, secrete to create a sticky mess on sidewalks and vehicles unlucky enough to be under an infested tree. The trees also become blackened with a fungus called sooty mold as a result.

Although the pests are very small - with adults smaller than one-eighth of an inch - the nymphs grow a glassy white, umbrella-shape covering called a lerp. The lerp makes them more visible and also protects them from pesticide applications, Fiksdal said.

The $30,000 project is being paid for by the city Department of Recreation and Parks, the Los Angeles Zoo and the city Bureau of Street Services' Street Tree Division. Other agencies cooperating in the program include the Los Angeles County Sanitation District, city of Torrance Street Services, Stanford University and agencies from Orange County, San Diego County, the Bay Area and Australia.

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Map: SITE OF PEST-KILLING WASP RELEASE