NOTES ON THE SEASONAL DEVELOPMENT OF MEDETERA ALDRICHII WHEELER (DIPTERA. DOLICHOPIDAE) AS A PREDATOR OF THE DOUGLAS FIR BARK-BEETLE, DENDROCTONUS PSEUDOTSUGAE HOPKINS (1)

Abstract

In 1935, De Leon published a comprehensive paper on Medetera aldrichii as a predator ol Dendroctonus monticolae Hopk., in western white pine and lodgepole pine in Washington. The following data may prove of value because a different species of bark-beetle is involved and additional information is given. The observations were made in 1941 and 1942 at the Trinity Valley Forest Insect Field Station, 22 miles from Vernon. This locality is 2,100 feet above sea level in a mixed timber stand of western larch, Douglas fir, western red cedar, Engelmann spruce, western hemlock, and western white pine. D. pseudotsugae breeds in Douglas fir, and occasionally in western larch.