Catastrophic defoliation is an important, little understood feature of many forested landscapes.
Efforts to document ecosystem level effects of insect outbreaks have lagged substantially behind efforts to understand individual insect populations and their regulatory controls. But system-level response experiments tell only part of the story. In particular, these studies miss the part of the story dealing with internal reallocations and feedbacks. These include shifts in soil organic matter quality due to fine root death and frass inputs, shifts in decomposition rates due to changes in root and foliar secondary chemistry, and shifts in nitrogen loss as NH3 volatilization becomes a major vector of N loss. The KBS LTER Gypsy Moth Project is examining more closely the effects of insect outbreaks in an in situ whole-system context.