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(04/29/2001) 300,000 acres in Oregon now covered by non-native European gorse, invasive plant is choking out native plants and wildlife and still spreading as seeds hitch rides on car tires and forest equipment. The dark-green shrub with delicate yellow flowers may not appear ominous, but gorse is slowly choking out native Oregon plants as well as blocking people and wildlife from areas along the south coast. In 1936, when it was still under control, its spines helped fuel a fire that burned Bandon to the ground. Today, it has rendered about 300,000 acres unusable.
The European weed fills fields, covers hillsides and is nearly impossible to eliminate. Kill one, and its offspring rise from the soil. The seeds can live up to 100 years in the earth. "It's pretty much a never-ending battle," said Shorty Dow, estate representative for Bandon Dunes Golf Resort, which spent millions to reclaim enough land from gorse to build a world-recognized golf resort in 1999.
Gorse isn't just staying on the coast; it's spreading inland. The Oregon Department of Agriculture lists more than 100 sites between Portland and north of Grants Pass where gorse is growing, and it was spread there by humans.
Coos County commissioners agreed last month to create a weed board to combat the nasty prickly bush, among other noxious weeds. Meanwhile, the Department of Agriculture is trying to stop people from spreading the shrub as the agency awaits federal approval of gorse-killing insects.
Ken French, Department of Agriculture noxious-weed specialist, said most of the spread is unintentional, although he knows of at least one case in which a Roseburg woman planted the weed in her front yard because it was pretty. Accidental spreading usually comes from gorse seeds lodged in tire treads or stuck in equipment used in the forest, French said. Washing the tires and equipment helps reduce its expansion.
Lord George Bennett reportedly brought gorse to Bandon from his native Ireland to use as a hedgerow in the late 1800s. Because Oregon lacked the insects to keep it under control, the weed flourished.
The Department of Agriculture, which tries to avoid using herbicides, is awaiting approval to test at least two more insects, a moth and a beetle-like insect, that could help control the weed. The insects go through at least five years of study to ensure they attack only gorse or other noxious weeds. "If they feed on anything else, that kicks them out of the process," said Tim Butler, noxious-weed program manager for the Department of Agriculture.
A seed weevil that consumes gorse seeds was released many years ago, though not in Bandon, and is thought to be helping control the weed's spread, Butler said. The department also dropped spider mites on gorse four years ago. The mites suck the juice from the plant, like aphids attack roses. (Sources)