Forests are complex ecosystems. They are constantly changing as a result of tree growth, variations in weather and climate, and disturbances from fire, pathogens, and other stressors. A huge number of insects and diseases have the potential to negatively affect tree species in the U.S.
The Forest Health Monitoring (FHM) Program produces annual national reports that present forest status and trends from a national perspective, introduce new techniques for analyzing forest health data, and summarize results from recently completed Evaluation Monitoring projects funded through the FHM national program. The FHM tracks these ongoing changes — every year, across the nation — as a forest health check up. The annual reports contains short- and long-term forest health assessments for the continental U.S., Alaska, Hawaii, Puerto Rico, and the U.S. Virgin Islands. Users can search reports and chapters by year (from 2001) or topic. Highlights and additional resources are also included.