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Abstract
On the Mt. Mitchell area during the summer of 1968, 20 stands of Fraser fir,
Abies fraseri (Pursh) Poir., infested by the balsam woolly aphid,
Adelges piceae (Ratzeburg), were examined for native and previously imported predators of the aphid.
Laricobius erichsonii Bosenhauer (Coleoptera: Derodontidae) was the only foreign predator located, and it occurred on 30 percent of the sites sampled. In terms of distribution, this predator ranked below the native species, Allothrombium mitchelli Davis (Acarina: Trombidiidae), Bdellidae (Acarina), and
Hemerobius spp. (Neuroptera: Hemerobiidae).
Aphidecta obliterata (L.) (Coleoptera: Coccinellidae) was not found at sites where it was previously released nor at other sites. Its survival, in the face of naturally diminishing populations of the aphid, is regarded as tenuous at best.
Citation
Fedde, Gerhard F. 1972. Status of Imported and Native Predators of the Balsam Woolly Aphid on Mt. Mitchell, North Carolina. Res. Note SE-175. Asheville, NC: U.S. Department of Agriculture, Forest Service, Southeastern Forest Experiment Station. 4 p.
