Currently, the emerald ash borer has been found in trees only in Washington County, where a quarantine prohibits moving ash (Fraxinus) or fringe tree (Chionanthus) wood in or out of the area.
Oregon ash thrives in many areas of western Oregon, from floodplains to foothills. But this key tree is threatened by the spread of an invasive beetle known as the emerald ash borer, which kills ash. This ...
Covers the history of yellow starthistle (Centaurea solstitialis L.) invasion of the Pacific Northwest and describes current infestation levels in Oregon and Washington. Provides basic information regarding yellow ...
Larry L. Larson, Roger Sheley, Michael McInnis, Gary Kiemnec |
Jan 2008 |
Extension Catalog publicationPeer reviewed (Orange level)
Russian olive trees are fast-growing plants that since the 1950s have become invasive throughout many areas of the Inland Pacific Northwest, particularly in riparian ecosystems. They form impenetrable masses, create ...
Woody knotweeds are listed as noxious weeds throughout most of the United States. This publication briefly describes the characteristics and biology of four species of woody knotweeds and summarizes management and ...
Robert Emanuel, Andy Hulting, Rebecca Koepke-Hill |
Jun 2011 |
Extension Catalog publicationPeer reviewed (Orange level)