Induced increase of soft scale: Imbalance between scales and natural enemies on walnut trees in northern California results in scale population increases
AuthorsA. E. Michelbacher
Authors AffiliationsA. E. Michelbacher is Professor of Entomology, University of California, Berkeley; Stephen Hitchcock is Research Assistant in Entomology, University of California, Berkeley.
Hilgardia 12(11):13-13. DOI:10.3733/ca.v012n11p13. November 1958.
The principal natural enemies of soft scales attacking walnut trees in northern California are small winged parasites easily killed by trace amounts of insecticides. If undisturbed, the parasites are able to maintain the scale population much below an economic level.
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