Research
Ecological restoration is a practice that seeks to heal degraded ecosystems by reestablishing native species, structural characteristics, and ecological processes. For over 40 years, Dr. Wally Covington has been studying the fire-adapted forests in the western US, working with colleagues to document the historic conditions and processes, and the changes observed since a distinct, notable change in the natural process of these forests – FIRE.
What We Know About The Past
In the Southwest and Intermountain West, conifer forests co-evolved with fire. These regions are dominated by forests and grasslands that burned as frequently as every 5 years: ponderosa pine stands with and without oak; dry-mixed conifer forests that contain ponderosa pine, Douglas-fir, Southwest pine and aspen; and many of our grasslands.
What Happened
European settlement removed fire from the system – as early as 1870 through grazing of sheep and cows, and more efficiently after the Forest Service’s “10am fire policy” following the fires of 1909. As a result of fire exclusion and logging of old-growth trees, many of these forests are now dominated by unnaturally dense thickets of small trees, and lack their once diverse understory of grasses, sedges, and forbs. Forests in this condition are highly susceptible to damaging, stand-replacing fires and increased insect and disease epidemics.
What We Do
Restoration of these forests centers on reintroducing frequent, low-severity surface fires—often after thinning dense stands—and reestablishing productive understory plant communities.
Variability across the landscape exists in terms of forest density and composition; the goal of restoration is to capture this system variability using historical tree remnants (snags, stumps and logs) at each site. Treatments are designed to emulate forest structure, composition, and function characteristic of the natural evolutionary environment. Additionally, all trees alive at the time of fire exclusion (presettlement) are retained within the stand.