Foreign Predator Introductions for Control of the Balsam Woolly Aphid in the Pacific Northwest

• DOI: 10.1093/jee/60.1.140
• Publication Date: 2015-01-14T00:00:31Z
• Authors: R. G. Mitchell; K. H. Wright

The balsam woolly aphid, Adelges piceae (Ratzeburg), an import from Europe, causes major damage to true fir forests in North America. A program has been underway since 1957 control the pest Oregon and Washington by introducing insect predators. Twenty-three species have introduced 7 countries throughout world. They include 15 of beetles, 4 flies, 3 lacewings, 1 bug. Three Aphidoletes thompsoni Möhn, Cremifania nigrocellulata Czerny, Leucopis obscura Haliday 2 Laricobius erichsonii Rosenhauer Pullus impexus (Mulsant), are successfully established. prey on aphid but so far not sufficiently reduced populations prevent tree killing. Reasons for their failure poor synchronization predator-prey seasonal habits, inadequate searching ability predators, inability host trees withstand even light aphid. Search more effective predators is continuing. problem expected decrease as present virgin old converted, under management, less susceptible young forests. Aphid may become relatively such forest conditions.