Pre-treatment studies of arboreal arthropods

Tim D. Schowalter

Department of Entomology
404 Life Sciences Bldg.
Louisiana State University
Baton Rouge, LA 70803
(225) 578-1634
tschowalter@agcenter.lsu.edu

The following is the abstract of a paper describing patterns of abundance and community composition of arboreal arthropods among DEMO sites prior to treatment.

Progar, R. A., T. D. Schowalter, and T. Work. 1999. Arboreal invertebrate responses to varying levels and patterns of green-tree retention in northwestern forests. Northwest Science 73 (Special Issue): 77-86.

Canopy arthropods play an important role in forest ecosystems and are sensitive to anthropogenic disturbances. The DEMO (Demonstration of Ecosystem Management Options) study investigates the influence of varying levels and patterns of green-tree retention on diverse elements of northwestern forest ecosystems. In this paper we review the literature on forest management effects on canopy arthropods and describe research in progress on the response of arboreal arthropod communities to retention harvests in the Pacific Northwest. Pre-treatment foliage was pruned and canopy arthropods collected from dominant overstory and understory vegetation within six treatment units in eight experimental blocks in western Oregon and Washington. Significant pre-treatment differences in abundance were found among blocks and treatments for several taxa in the overstory. Block-level differences reflect natural variation in the geographic distribution of arthropod taxa. Differences among treatment units may reflect the influence of local variation. Following harvest treatments, we expect to see changes in arthropod richness, abundance and functional group organization in dominant overstory and understory canopies reflecting the influence of magnitude and pattern of green-tree retention.