The seasonal biology of the obliquebanded leafroller, Choristoneura rosaceana (Harris), was studied to improve its management in Mid-Columbia area sweet cherry orchards. Overwintering OBLR larvae began to emerge from hibernacula at bud stage 2 (side green). Most overwintering larvae emerged from hibernacula within three weeks of first bud swell and...
During summer of 1998 and 1999, 34 and 10 vineyard sites, respectively, were sampled to assess spider mite pests and associated biological control by phytoseiid mites. Vineyards studied spanned five major valleys in western Oregon where grape production occurs. Leaf samples were taken from site perimeters and centers. One leaf...
The European hazelnut, Corylus avellana L., was imported into the U.S. in the late 1800's and is now grown throughout the Willamette Valley in Oregon. A native species of hazelnut, C. cornuta Marshall, is a common shrub found in forested areas of the Pacific Northwest. Foliage of both C. avellana...
The structuring of canopy arthropod communities was reviewed and investigated in relation to tree species diversity and its component factors, interspersion of different species and density of each tree species. Fifteen treatments of Douglas-fir (Pseudotsuga menziesii) and red alder (Alnus rubra) (various densities and proportions of each) were randomly assigned...
Black vine weevil (BVW), Otiorhynchus sulcatus Fabricius, is a serious pest in cranberry, Vaccinium macrocarpon. Larvae feeding below the soil surface cause damage to the roots and underground stems. Knowledge is sparse in regard to the damage potential of BVW in Pacific Northwest cranberry beds. Control with insecticides is limited...
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...
In the past 10 years we have witnessed the beginnings of the study of soil ecology as a unified science, and the general realization by soil scientists, farmers, and land managers that many of the most important economic aspects of soil health are controlled by biological factors. This research focuses...
Landscape heterogeneity is thought to differ among farm management types (i.e. organic and conventional), and this difference is hypothesized to result in variations in pest control by natural enemies. However, it is unclear if these variations in pest control are driven by landscape structure or by farm management practices themselves....
The predatory mite Typhlodromus pyri (Acari: Phytoseiidae) is the predominant species in cool climate Pacific Northwest vineyards and a principal predator of pest mites including the grapevine rust mite Calepitrimerus vitis (Acari: Eriophyidae). In recent years vineyards have been experiencing C. vitis population outbreaks leading to increased economic damage from...
The twospotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae), is a
worldwide pest of numerous agronomic and horticultural plants. Conservation
biological control of this pest can be unreliable due to asynchrony of natural enemies
and certain horticultural practices that have a direct or indirect affect on natural
enemies and the...