This study was initiated in the Spring of 1966 for the purpose of
determining the present status and effectiveness of imported parasitic
wasps of the pea aphid in the Willamette Valley of western Oregon.
The pea aphid is a serious pest throughout the pea and alfalfa
growing regions of the...
A complete taxonomic review of the Family Eviphididae was
made for the first time. The family was found to contain forty-nine
species and five genera. The genera included were: Eviphis
Berlese, Scarabaspis Womersley, Alliphis Halbert, Pelethiphis
Berlese, and Thinoseius Halbert.
The new species described were: Eviphis oregonensis from
Deschutes County,...
Food habits and biology of five species of Pleocoma larvae were
studied at a dozen forested sites in western Oregon between May 1960
and December 1961.
First instar Pleocoma hatch in late summer and moult to second
instars in early fall. Second and subsequent instars moult annually
between mid-summer and...
The effect of competition on the brood survival of the Douglas fir
beetle Dendroctonus pseudotsugae Hopkins, in down or windthrown
Douglas-fir Pseudotsuga menziesii (Mirb.) Franco was studied in the
field and the laboratory. The investigation of the role of competition
in the population dynamics of the beetle had four objectives:...
Field biology studies of three grain aphids, Macrosiphum
avenae (Fabr.), Acyrthosiphon dirhodum (Walker), and Rhopalosiphum
padi (L.) were conducted near Corvallis, Oregon, from 1961 to
1964.
Populations of M. avenae were found on grain plants, and
alatae entering spring barley may have been from wheat fields. Specimens
were found more...
