Published September 1989. 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
Four sampling techniques were evaluated to estimate clover aphid, Nearctaphis bakeri
(Cowen), abundance in red clover fields in the Willamette Valley. The Berlese funnel method
detected one to four times more aphids than other sampling techniques. Visual assessment
often underestimated the high aphid densities during the flowering and seeding of...
In Oregon’s northern Willamette Valley, cabbage maggot (CM), Delia radicum (L.) (Diptera: Anthomyiidae) often renders Brassica root crops unmarketable. Scheduled insecticides are the only current control. Studies were conducted to: 1) describe and characterize spring emergence of CM flies and their seasonal flight activity relative to degree-day (DD) accumulations; 2)...
Short shoot syndrome (SSS) is an increasingly important problem of grapevines in Oregon and, more recently, in Washington. Symptoms associated with SSS include puckered or malformed basal leaves, scarred and severely stunted shoot growth, and loss of grape clusters. In severe cases, complete crop loss
results from abortion of affected...