'Major agricultural pest' puts orchards, winegrapes at risk

By MITCH LIES

Capital Press

HOOD RIVER, Ore. -- The brown marmorated stink bug, which has uprooted pest control programs in the mid-Atlantic states, has been found in two more sites in Oregon, both prominent orchard areas.

Oregon State University researchers reported June 13 that they have found the pest in the cities of Hood River and Phoenix.

The findings are significant, Oregon State University entomologist Peter Shearer said, because of their proximity to orchard crops.

"This thing is a major agricultural pest, and it goes after orchard crops," Shearer said.

"We suspect there is an infestation that has started in Hood River," Shearer said.

The stink bug was first detected in Oregon in 2004 in Portland. It has since been found in Salem, Corvallis, Sandy, Troutdale, east as far as Arlington, and in Deschutes County. The pest also has been found in Vancouver, Wash., and near Longview, Wash., and was recently found in Idaho for the first time, in Nampa.

In addition to orchard fruit crops, the pest attacks winegrapes and hazelnuts, Shearer said, putting at risk two prominent Willamette Valley crops.

So far researchers have not found the pest in commercial crops in the Northwest.

Shearer said it took several years for the pest to expand from cities to crops in the mid-Atlantic region, but when it did, the effects were substantial.

"In 2010, the population exploded," Shearer said. "It destroyed 50 percent of the Pennsylvania peach crop, and did $40 million in damage to the mid-Atlantic apple industry."

The pest also attacks sweet corn, vegetables, soy beans, field corn and ornamentals, Shearer said.

"All of those commodities have been severely attacked in the mid-Atlantic states," Shearer said.

"It is just a matter of time before it becomes an issue in our cropping systems," he said.

The pest damages crops by feeding on fruit, foliage and even trunks of thin-skinned ornamentals. The feeding damage subsequently provides entry points for decay-causing pathogens.

The pest is hard to kill, scientists say, and has disrupted integrated pest management programs in the mid-Atlantic states.

Shearer and other scientists are working on what he says could be a saving grace in the form of a parasitic wasp that feeds on the bug's eggs.

"We know that it is effective in the lab," he said. "But the concern is screening this against our native stinkbugs," he said. "There are beneficial stink bugs that are predators, and we don't want this parasite to attack them."

Researchers first found the bug in Hood River June 7. They found additional bugs June 11. The Phoenix discovery came June 11.

The bug is believed to be widespread in Portland. It expands its range primarily by hitching rides on vehicles, scientists say.