University of California

Calico scale on walnuts: Problem of soft scales on walnut increasing but natural enemies still exert suppressing influence on calico scale


A. E. Michelbacher
Stephen Hitchcock

Authors Affiliations

A. E. Michelbacher is Professor of Entomology, University of California, Berkeley; Stephen Hitchcock is Research Assistant in Entomology, University of California, Berkeley.

Publication Information

Hilgardia 10(9):6-6. DOI:10.3733/ca.v010n09p6. September 1956.

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The Audubon's warbler and a wasp parasite work together to hold the calico scale—potentially destructive on walnuts —under control. This occurs even under conditions where—because of the tendency of the newer insecticides to interfere with natural enemies—other un-armored scale population has increased.

Michelbacher A, Hitchcock S. 1956. Calico scale on walnuts: Problem of soft scales on walnut increasing but natural enemies still exert suppressing influence on calico scale. Hilgardia 10(9):6-6. DOI:10.3733/ca.v010n09p6

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