University of California

Factors affecting the distribution of the Monterey pine cone beetle (Conophthorus radiatae Hopkins) in central California


Charles H. Schaefer

Author Affiliations

Charles H. Schaefer was formerly a Research Assistant in the Department of Entomology and Parasitology, University of California, Berkeley.

Publication Information

Hilgardia 34(4):79-103. DOI:10.3733/hilg.v34n04p079. March 1963.

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This paper reports a series of laboratory and field studies of the Monterey pine cone beetle. The author devoted much time and effort, on both the west arid east slopes of the Berkeley Hills, in determining the effects of humidity and temperature on the insect’s survival. His principal concern was to determine its ability to inhabit areas outside the coastal fog belt. • It was definitely established that the beetle’s life cycle is favored by moderate temperatures and a plentiful supply of moisture. This was evident by its prevalence on the seaward side of the range, where fogs are frequent and summer heat is not excessive. On the other hand, when the insects were “planted” on the east side, near San Pablo Dam, the mortality rate was very high, thus showing the adverse effects of heat and low humidity. • The present study represents the second portion of the author’s Ph.D. thesis; the first portion is cited herein under “(Schaefer (1962)).”

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Schaefer C. 1963. Factors affecting the distribution of the Monterey pine cone beetle (Conophthorus radiatae Hopkins) in central California. Hilgardia 34(4):79-103. DOI:10.3733/hilg.v34n04p079
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