Published May 1980. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog
The Pacific Northwest is an internationally important region for the production of Brassica seed and other seed crops including grass seed. Oregon lawmakers mandated research into the co-existence of canola (Brassica napus) with other Brassica production in the Willamette Valley and House Bill 2427 was signed into law in 2013,...
Mortality of containerized western white pine seedlings outplanted on the Bonners Ferry Ranger District, Idaho Panhandle National Forests, was probably due to extensive root infection by Fusarium oxysporum. Diseased seedlings had chlorotic foliage, needle tip dieback, and severe twisting of the needles that indicated wilting. Most root tips of diseased...
Four key aspects of the relationship between predatory hoverflies and the aphid pest Brevicoryne brassicae L. on broccoli were investigated in the Willamette Valley, Oregon USA: 1) the relationship between aphid density and hoverfly oviposition, 2) the larval voracity of key hoverfly species, 3) the preferences of hoverflies and broccoli...
Blueberry production in Oregon is highly reliant upon the ecosystem services of native pollinators, which provide as much as a quarter of the total pollination services received by Blueberry growers. However, the health of these pollinator populations may be affected in yet unforeseen ways as growers adopt new pest management...
Ceratomyxa shasta is a myxozoan parasite that infects salmonid fishes causing the disease ceratomyxosis that is characterized by severe hemorrhage and necrosis of the intestine and death of the fish host. Ceratomyxa shasta is endemic to the Pacific Northwestern United States and Canada, where epizootics are reported for both wild...
Root rot of sweet corn in western Oregon and Washington is a significant disease that
can reduce yield of intolerant cultivars of processed sweet corn by fifty percent. Root rot
is caused by a complex of soilborne organisms, including Drechslera sp., Phoma
terrestris, and Pythium arrhenomanes. Processors have adopted tolerant...
The hemlock woolly adelgid, Adelges tsugae, is causing widespread mortality of eastern hemlock, Tsuga canadensis, in the eastern United States. In the West, A. tsugae causes negligible damage to western hemlock, Tsuga heterophylla. Host tolerance traits and presence of endemic predators may be contributing to the relative tolerance of western...