Predatory insects and spiders were collected from apple orchards in two
geographic regions of Central Washington State, United States of America to
assess seasonal phenology and diversity of the generalist predator
community. Arthropods were collected from orchard canopy every 3–7 days over
two growing seasons (March–October) at seven organically managed and two
insecticide-free orchards. Over 35 000 specimens and 80 species of spiders
(Araneae), ladybeetles (Coleoptera: Coccinellidae), lacewings (Neuroptera),
and predatory true bugs (Hemiptera) were collected. Composition of insect
and spider communities differed between the two geographic regions.
Indicator species analysis identified several species that had a significant
association with one of the two regions. Counts of the most common taxa were
examined in detail on a calendar date basis to determine seasonal phenology
of adult and immature stages. We observed substantial differences among taxa
in number of generations, seasonal timing of first appearance in orchards,
overwintering stages, and seasonal occurrence of the adult and immature life
stages in orchards. Understanding seasonal phenology of natural enemies in
orchards is a core requirement in integrated pest management programs for
apple pests, and results of this study provide this information for the
generalist predator community of orchards in the Pacific Northwest.