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NALDC Record Details:
Phenology of emergence from artificial overwintering shelters by some predatory arthropods common in pear orchards of the Pacific Northwest
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The phenology of emergence from artificial overwintering shelters that had been placed in pear orchards located near Yakima, Washington, was determined for the green lace-wing Chrysopa nigricornis Burmeister, the predatory mirid Deraeocoris brevis (Uhler), and the brown lacewing Hemerobius ovalis Carpenter. Cumulative emergence from shelters was determined in 2001 and 2002 on both a calendar-date and degree-day basis. Similar data for a major pear pest, pear psylla, Cacopsylla pyricola (Forster), were also collected for these same shelters. Pear psylla and H. ovalis emerged earliest, both taxa completing emergence by early March (120 degree-days accumulated from early January). Deraeocoris brevis emerged beginning in late February and finished emergence by early April (150 degree-days for 90% emergence). Chrysopa nigricornis emerged considerably later than the other species, and completed emergence by late May or early June. Calendar-date emergence is also shown for spiders (Araneae) and Anthocoridae (Heteroptera), which occurred at lower numbers in the shelters. The anthocorids, Orius tristicolor White and three species of Anthocoris, emerged from shelters in February and March, while spiders emerged over a long interval between March and May.
Journal of the Entomological Society of British Columbia 2004 Dec., v. 101
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