10:09 AM PDT on Saturday, June 18, 2005

Associated Press

JOSEPH, Ore. - Geologists come here from around the world to look at the textbook-perfect glacial moraines rising above Wallowa Lake, but what they increasingly see is a proliferation of weeds growing on the symmetrical rocky knolls.

One of the most prominent is a spiny, flowering variety called spotted knapweed that elk refuse to eat. The weed can trigger soil erosion, in turn causing the gradual slide of the moraines into the gemlike 280-foot-deep lake.

AP

Ellen Morris Bishop spots a bunch of spotted knapweed on a moraine above Wallowa Lake in Joseph, Ore. Bishop helped organize a group of local volunteers known as the Wallow County Weed Warriors to pull the weeds out by the roots as they envelop the moraines.

Local volunteers calling themselves the Wallowa County Weed Warriors climb the 950-foot-high moraines on weekends and evenings to pull pesky knapweeds out by the roots.

"We are fighting alien terrorists," said geologist Ellen Morris Bishop, an organizer of the 2-year-old group and author of "In Search of Ancient Oregon. These plants are hostile to humans, and they basically armor-plate a landscape so it's theirs and not ours anymore."

Coffee shop talk here often centers on rising cougar numbers and the possibility that gray wolves might again become part of life in this northeastern corner of the state. But Wallowa County's most costly problem may be invasive weeds, land managers say.

Oregon lists 105 noxious weeds, but a mere 21 of those varieties cost taxpayers $83 million a year - largely in grazing and timberland losses, said Tim Butler, manager of the Oregon Department of Agriculture's noxious weed program.

The state's most notorious invasive weed probably is scotch broom, he said. Found on 7 million acres of Western and Central Oregon, it has spread as far east as Pendleton and alone accounts for $47 million a year in lost revenues, Butler said.

Small infestations of noxious weeds have taken hold in a quarter of the 652,488-acre Hells Canyon National Recreation Area in Wallowa County, and they could grow into large infestations without attention, said Leigh Dawson, U.S. Forest Service noxious-weed coordinator in Enterprise.

One of the Forest Service's biggest concerns is stopping the spread of yellow star thistle into Hells Canyon. It can make hiking an ordeal because of its needle-sharp thorns. Another concern is leafy spurge, which exudes a sap that can cause temporary blindness and boils when it comes in contact with eyes and skin.

Elsewhere, Dalmatian toadflax sometimes grows 4 feet tall in Hells Canyon's draws, and Japanese knotweed clogs streamside areas.

Common bugloss, rush skeletonweed, whitetop and Medusa head are other havoc-wreaking varieties.

Yellow star thistle chokes 45 miles of Idaho's Salmon River corridor, in some spots from river to rim tops, and appears to be moving toward Hells Canyon, said Lynn Danly, rangeland specialist with the U.S. Bureau of Land Management in Cottonwood, Idaho. She watched the Salmon River's Rattlesnake Ridge area go from native plants to "a sea of yellow star thistle" in nine years.

That's a scary proposition in Wallowa County. If the infestation reaches Hells Canyon, the county stands to lose habitat for wildlife and birds and suffer unprecedented soil erosion.

The Forest Service's Dawson believes climate factors and the various ways people accidentally transport seeds into the canyon play a larger role in the spread of weeds than the removal of domestic sheep.

In the meantime, the Forest Service will rely on weed-pulling teams, herbicides and insects to attack the interlopers - and hope that those can whack the weeds back into submission.