The Western Pine Beetle and Forest Health: Historical Approaches and Contemporary Consequences

Abstract

During the 20th century, forest entomologists developed a knowledge base about the impact of various insects on tree species, most often with an eye toward controlling those that caused the greatest damage to forest resources. Based in part on extensive tree mortality attributable to insect activity and identified by forest entomologists, contemporary forest managers have concluded that parts of America’s forests are undergoing a health crisis (Brooks 1996); however, concerns about forest health are not novel to recent decades, but can be traced to the beginning of the 20th century. In the early decades of the past century, forest entomologists used terms that centered on the metaphor of health in their research on the biology, ecology, and control of forest insects. Researchers focused on tree growth as one of the best ways to assess the impact of insects on the forest; and this, in turn, served as a basis for decisions about control measures. Trees with reduced vigor are more vulnerable to insect damage; and tree mortality, when it occurs on a large enough scale, lowers the overall productivity of the forest. The control methods devised to protect forest resources from insect damage reflected the focus and emphasis on tree vigor or part of what contemporary forest managers would include under the broader umbrella of “forest health.” Forest entomologists helped to develop control methods, such as sanitation logging, to improve the overall health of a given stand. In this article, I focus on bark beetles and the western pine beetle, Dendcroctonus The Western Pine Beetle and Forest Health: Historical Approaches and Contemporary Consequences