Insects & Diseases

Native forest insects and diseases are important components of forest ecosystems in Oregon and Washington.  By affecting the growth and mortality of individual trees, they influence the species composition, stand structure, and ecological succession of forest stands.  They also have many other important ecological roles, such as recycling nutrients, pollinating plants, and providing food for wildlife.  Healthy forest ecosystems in the Pacific Northwest include thousands of species of forest insects and pathogens.


Publications and Reports

Annual   Forest Health Highlights reports are available for Oregon and Washington from 1998 to the present as well as  Forest Insect and Disease Conditions reports that date back to 1933.  View 1-page Forest Disease Management Notes for 50+ forest tree diseases and many other publications and reports about western forest insects and diseases.


Western Forest Insects & Diseases

View a catalog of online publications and links about western forest insects and diseases.

Currently featuredDouglas-fir Tussock Moth, a native defoliator


Field Guides and General Websites