Published July 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
A pest management program for Tetranychus urticae Koch in Oregon
peppermint was developed based on studies of sampling, plant phenology,
population dynamics and damage thresholds.
A sample size of 45 leaves provided a confidence level of 90%
and a confidence interval of 50%. Estimation of the sample mean was
based...
Glyptholaspis americana (Berl.), G. confusa (Foa) and
deutonymphal Parasitus sp. were studied to determine the function
of the tritosternum. Studies were conducted on feeding, cleaning,
temperature and humidity sensitivity using intact individuals and
individuals whose tritosterna had been surgically removed.
The tritosternum was found to have two functions:
1) As...
The purpose of this study was to determine the relative resistance
of genetic lines of hops, Humulus lupulus (Linn.) to the
two-spotted spider mite, Tetranychus urticae (Koch) in western
Oregon.
Approximately three-hundred genetic lines of hops were
screened under insectory conditions during the 1965 growing season
at Corvallis, Oregon. Reduction...