Plant Community Types Of The Chugach National Forest

Between 1977 and 1997, 4000 ha were burned to promote regeneration of tree and shrub species used for browse by moose (Alces alces) in the Kenai Mountains. Species composition was documented along burned and unburned transects at 17 prescribed burn sites. Relationships among initial vegetation composition, physical site characteristics, browse species abundance, and competitive herbaceous vegetation were examined to determine controls on browse species regeneration after prescribed burning. Browse species abundance after burning was inversely related to Calamagrostis canadensis Michx. Beauv. (bluejoint reedgrass) abundance prior to burning. Calamagrostis canadensis abundance was related to specific landscape characteristics. Depositional slopes, such as fluvial valley bottoms and toe slopes, often featured soils with deep, loamy surface horizons. Sites with these characteristics generally showed large increases in C. canadensis cover after prescribed burning, even when C. canadensis was a low percentage (3 percent) of the canopy cover prior to burning. The most important preburn variables for predicting postburn browse species abundance were preburn C. canadensis cover and the type of surficial deposit. Site conditions that are favorable to C. canadensis may be problematic for successful regeneration of browse species, especially if browse species are not present in the initial composition.