Environmental Entomology (1984) 13, 179-183

Devin P. Carroll and Robert F. Luck (1984)
Within-tree distribution of California red scale, Aonidiella aurantii (Maskell) (Homoptera: Diaspididae), and its parasitoid Comperiella bifasciata Howard (Hymenoptera: Encyrtidae) on orange trees in the San Joaquin Valley
Environmental Entomology 13 (1), 179-183
Abstract: Within-tree distribution of California red scale (CRS), Aonidiella aurantii (Maskell), and its parasitoid Comperiella bifasciata Howard on host substrates (fruit, leaf, twig, wood) and in tree sectors (north, south, east, west; upper and lower halves) was studied through 1 year on five navel orange trees in a grove in California's San Joaquin Valley. CRS density was relatively low on leaves and twigs and high on wood and fruit. However, more than 90% of crown area was leaf surface. Thus, leaf-, wood-, and fruit-dwelling CRS each contributed substantially to the CRS population. CRS density was relatively low on the south faces and upper halves of the trees, especially during and after summer. C. bifasciata parasitized CRS on fruit in the highest percentage, followed, in order, by those on leaves, twigs, and wood. During hot summer periods parasitization decreased on southern tree sectors on all substrates except fruit. On leaves, parasitization was heaviest on eastern tree sectors.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)

Research topic(s) for pests/diseases/weeds:
biocontrol - natural enemies
environment - cropping system/rotation
Research topic(s) for beneficials or antagonists:
environment/habitat manipulation

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Aonidiella aurantii	Citrus (genus)	U.S.A. (SW)
Comperiella bifasciata (parasitoid)	Aonidiella aurantii	Citrus (genus)	U.S.A. (SW)