More than 30 feet above the ground, Brent Olson steers a mechanical lift across the outstretched limbs of a bigleaf maple tree. He aims his binoculars toward the trunks of two towering cottonwoods beyond, scanning for the enemy.
“They could be anywhere in there,” Olson says.
Across the street in this Tukwila neighborhood just south of Seattle, a resident swishes jump shots into a driveway hoop, while another loads children into a minivan, perhaps for a quick trip to the Wendy’s restaurant a few blocks away.
The suburban scene hardly resembles a battlefield, but Olson (’03 Entomology, ’04 M.S. Environmental Science) is on the front lines in a new battle to keep destructive insects from invading Washington. Working for the Washington State Department of Agriculture, he has spent the summer searching Tukwila’s trees for signs of citrus longhorned beetles.
Agriculture experts believe the Korean wood-boring beetle could devastate native hardwood forests, fruit orchards, and urban landscapes. In 2001, the insect joined a list of dreaded pests in the Pacific Northwest. Also on that list is the infamous gypsy moth.
Washington agriculture officials hope they’ve caught the citrus longhorned beetle before it can make an encore appearance.
The beetles hitched a ride on ornamental plants shipped from Korea to Bonsai Nursery, a small business overlooking Interstate 5. Scientists believe that five of the beetles escaped from bore holes in the plants into the surrounding neighborhood, setting off a five-year eradication program.
Midway through that project, Olson and his fellow surveyors have yet to find one of the large black beetles with white splotches. But Olson keeps looking for signs that the beetle’s larvae have been tunneling away unseen.
“Just because on this side [of a tree] you don’t see anything, on the other side there could be a hundred holes,” he says, swiveling the binoculars toward a black locust.
The stakes are so high because, despite their name, citrus longhorned beetles will attack the Northwest’s plentiful maple trees and more than 40 other common hardwoods, from alders to apples. With no natural predators, the beetle larvae bore unmolested through trunks as they feed, severing tissues that carry nutrients and water and slowly starving the plant.
A closely related pest, the Asian longhorned beetle, previously invaded areas of North America, including New York and Chicago, where officials spent at least $80 million and destroyed 7,000 trees to fight the infestations.
Besides invading longhorned beetles, Washington’s agricultural experts watch for Japanese beetles, various fruit moths, and another emerging threat, the emerald ash borer.
Richard Zack (’82 Ph.D. Entomology), interim chair of WSU’s entomology department, says evidence of the havoc that invasive insects inflict is as close as the nearest grain field or apple orchard. Once fully established, foreign insects, such as the Russian wheat aphid and the codling moth, are here forever.
In fact, says Zack, about 70 percent of agricultural pest insects in Washington are not native to the state. New insects typically are more destructive than natives because they often arrive without the natural predators and diseases that kept them in check.
“If you can keep [a new invasive insect] from becoming established, in the long run you can save yourself an extremely large amount of money, because you don’t have to control it.”
While trying to keep small insects out of vast landscapes seems daunting, the annual gypsy moth program proves it can be done.
“We’ve got a 30-year history of keeping gypsy moths out of the state due to this effort,” says Clinton Campbell (’81, ’83 M.S. Entomology). A pest survey specialist with the U.S. Department of Agriculture in Olympia who has spent much of his government career battling bugs, Campbell considers the gypsy moth program “a good news story in the results.”
Each year, Washington and neighboring states set thousands of paperboard traps baited with a scent lure to attract male moths. Most gypsy moths captured in the West are the European variety that moves with people from infested east-coast and Midwestern states. The usual remedy to halt an infestation is to spray the area with the biological pesticide Btk to kill the destructive caterpillars.
The price of the fight is high-about a million dollars a year for the state’s gypsy moth program alone-but Campbell says losing would be many times worse. A permanent infestation would trigger massive economic and environmental damage “from here to forever,” he says.
David Thompson (’70 Psych.) supervises a team of seasonal moth trappers in 10 southwestern Washington counties. In 1997, in the Dollars Corner area of Clark County, Thompson peered beneath an MG towed from Boston to find the undercarriage plastered with gypsy-moth eggs.
“We managed to step on that one real quick,” Thompson says. “The damage that this moth could do . . . is just astronomical.”