Can local stand and fire histories be used as tools for restoration across a broader geographic region?

Colorado’s ponderosa pine/Douglas-fir forests have increased in density and decreased in spatial heterogeneity due to fire suppression, climatic conditions, and of land use.  Recent large, intense fires in the wildland-urban interface of the Front Range have prompted managers and landowners to restore current forests to historical stand structures to mitigate fuels and fire risk. Studies of historical stand structure dynamics and fire history from a site in the South Platte basin have been key tools in restoration efforts in the Front Range. However, the applicability of these data to all ponderosa pine/ Douglas-fir forests is unknown. To address this, we compared the South Platte stand age and fire history data to similar data collected in an analogous watershed 150 miles to the north. Because fire occurrence is strongly climate-driven, mean fire intervals over large spatial scales were similar, but the timing of fire years and tree establishment periods differed. At local (plot) scales, fire intervals were more variable in the north, with longer intervals between recorded fires. Topography influenced fire and stand structure more strongly in the north. Historical land use also likely contributed to differences; the South Platte basin was extensively logged in the late 19^th century, creating a homogeneous forest structure, while logging in Cache la Poudre watershed occurred on smaller scales. These findings suggest that managers should develop restoration prescriptions from local historical information whenever possible. Where local data are unavailable, restoration targets should be based on data from similar vegetation and elevations, but should be adjusted for what is known of local land use history and topography.