California a Paradise for Pests as Well as People

They are tourists not even a chamber of commerce can love.

A virtual rogues’ gallery of migrant pests--drawn to California’s legendary clime and bountiful opportunities for advancement--are increasingly hitchhiking, sailing and flying into this state, often with devastating consequences: Crop losses alone cost about $1 billion a year.

That doesn’t include the money that cities, counties and the state spend to fight the bugs, or the potential harm done to the environment when desperate growers resort to chemicals.

The insects aren’t slowing down, either, as underscored by last week’s discovery in Tustin of a new insect that had felled a 125-year-old eucalyptus tree. The state discovers at least one new pest every 60 days, said Timothy Paine, a UC Riverside entomologist.

From 1955 to 1988, more than 200 infestations by exotic insects were discovered in California. During a six-year span starting in 1992, more than 67 were found, according to the state Department of Food and Agriculture.

Several insects have emerged as real hell raisers:

* California’s $30-billion wine and grape industry, as well as state and private landscaping interests, are threatened by the glassy-winged sharpshooter, which migrated years ago from the Southeast. The infestation prompted Gov. Gray Davis to recently ask the Legislature for $14 million to fight the leaf-hopping pest, which is destroying the state’s oleanders.

* Thousands of tiny wasps from Australia will be released this month in Orange County and throughout California to prey on the red gum lerp psyllid, which has been bleeding the state’s eucalyptus trees. Discovered in South El Monte in 1998, the psyllids spread almost overnight, feeding on eucalyptus tree fluids and leaving behind messy droppings.

* San Diego has its hands full with the Formosan subterranean termite, which in Hawaii has rendered homes uninhabitable within two years of invading them. Researchers are still struggling to find a way to control the insect, native to China.

And remember the fruit fly?

Just when it seems one type of fruit fly is reined in, another shows up to take its place. Fruit flies have forced the state to spend hundreds of millions of dollars on eradication in the last 10 years, said Larry Cooper, a spokesman for the state agriculture department.

“The last couple of years, we’ve seen a greater variety of fruit flies,” Cooper said “It’s one type of fruit fly after another, none naturally endemic to California.”

Officials and growers fear that the olive fruit fly, which made it to Southern California, will migrate to the San Joaquin Valley, the state’s center of olive production.

Then there are red fire ants and Africanized--so-called killer--bees. Orange County supervisors approved using $6 million in state money to eradicate the highly aggressive ant in January.

It’s no surprise that the epicenter for the state’s infestations is Southern California, which attracts foreign bugs for about the same reason it attracts tourists from Illinois.

“Southern California gets hit the worst because the weather’s great and it has wonderful plant diversity,” said Robert Dowell, the primary entomologist for the state agriculture department.

And forget Southern hospitality. California has done such a thorough job of bringing in exotic plant species that insects from India to Germany can feel at home here.

The state has literally reaped what it has sown, experts say.

“People plant things where they don’t belong,” said Donald Dahlsten, an entomologist at UC Berkeley who was in Los Angeles recently to monitor anti-lerp efforts. “Planting eucalyptuses in California was a mistake. We continue to suffer for that mistake.”

And Southern California’s position as a stalwart of international trade and tourism opens up seemingly infinite avenues for insect invasions, by land, sea and air. Even if California has some of the most stringent pest-exclusion practices in the nation, sheer logistics conspire to allow exotic insects in.

The problem is not new. California has long been vulnerable to exotic pest infestations.

Citrus fruit was routinely destroyed when Orange County was in its citrus grove heyday in decades past. And the turn of the century saw scourges that knocked certain agribusinesses, such as the grape and wine industry, clear out of some parts of California.

But recently it has seemed as if a particularly distasteful band of creepy crawlies has ganged up on the state--often in urban settings.

“We’ve been damned unlucky with some of the pests we’ve gotten recently,” said state entomologist Dowell. “A few years ago we had the ash whitefly. . . . Your shoes stuck on the sidewalk because of the honeydew they excreted. You’d walk to your car wearing a surgical mask. It was pretty disgusting.”

The damage wrought by nonnative pests has become more noticeable, said Nick Nisson, Orange County’s head entomologist, who said insects have been attacking the kind of ornamental plants that abound in urban areas. The eucalyptus is a case in point. Brought here from Australia in the 19th century, the tree can be found almost anywhere in populated regions of Southern California.

Before 1983, there were no known exotic pests attacking eucalyptus trees. In the 1980s, one emerged, the longhorn borer. Since 1990, nine insects that prey on the trees have appeared.

When Tustin workers cut down a diseased 125-year-old eucalyptus Monday, city administrator and certified arborist Pat Madsen found a new variety of the longhorn borer beetle on one of the logs, showing it off excitedly the way a child would show off a new Pokemon card.

“We’d heard it was around, but hadn’t seen it yet,” said Madsen, who trapped the beetle for later research. “This guy is tougher to control than the other one. The natural predator that we used to hunt down the original type of borer doesn’t work so well on this one.”

Universities such as UC Riverside and UC Berkeley are leading “bio-control” efforts to fight the longhorn borer and other invaders by finding their natural enemies.

For its part, the state agriculture department has asked the Legislature to extend a program that uses dogs to sniff out parcels containing fruits and plants, Cooper said. And the state continues to try to strengthen laws intended to crack down on quarantine violators.

The tactics received a further boost when President Clinton recently called for additional measures to be taken against invasive pests, Cooper said. Still, the chess match between bug and man rages on, with no end in sight.