Foliage consumption and nutrient dynamics in canopy insects.

Coweeta watersheds contain a varied and abundant fauna of insects, spiders, mites, and other invertebrates. Arthropods are usually inconspicuous, except when population excursions produce noticeable defoliation. Outbreaks of defoliating or wood-boring insect species clearly have an impact on the ecology of forested watersheds. Considerable information has been developed on the biology and ecology of economically important insect species. Much less is known about the ecology of economically unimportant insects, or even on the nonoutbreak phases of the important ones. This chapter characterizes feeding guilds of arthropods in forest canopies and uses guilds to describe between-tree and between-watershed variations in arthropod biomasses and standing crops of nutrients. Analysis of leaf area removed by insect feeding is a means of estimating herbivory.