Simon:

Insects aren't my specialty, but I read an article that agrees with your
assertion, at least regarding wood-feeding insects.

Hanula, J. L. 1996. Relationship of wood-feeding insects and coarse woody
debris. In McMinn, J.W. and D. A. Crossley, Jr. (eds.) Biodiversity and coarse
woody debris in southern forests, proceedings of the workshop on coarse woody
debris in southern forests: effects on biodiversity. General Technical Report
SE-94. U.S. Department of Agriculture, Forest Service, Southern Research
Station. 146 pp.

This publication is publicly available for free download (.pdf format) from:
http://www.srs.fs.fed.us/pubs/index.jsp

From the abstract: "Although a large amount of literature exists, most of it
focuses on relatively few, commercially important insects and provides little
information about their role in CWD decomposition, nutrient cycling, and energy
transfer."

Donna Scheungrab
Department of Forestry, Box 8002
North Carolina State University
Raleigh, NC 27695
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