Fire Effects in a Montane Wetland, Central Cascade Range, Oregon

Abstract

The stand-replacing Charlton, OR wildfire of 1996 burned several vegetation transects established before the fire, providing an opportunity to document recovery in one upland and five wetland vegetation zones over a 12-year period. Total mean percent cover of vegetation recovered to about 48% of pre-burn levels by year 12. Total cover increased slightly in Carex fen, but decreased in the other five zones. Fire damage was inversely proportional to moisture gradient, and recovery more or less directly proportional to the gradient. Upland Tsuga mertensiana forest sustained the greatest damage and showed the least recovery by year 12, followed by seasonally-flooded Polytrichum commune moss bed, Xerophyllum tenax ecotone, Vaccinium uliginosum shrub swamp, grass-dominated fen, and Carex fen. A transient soil crust of early-seral bryophytes occurred in upland Tsuga mertensiana forest. Cover of shrub, forb, grass, and moss layers declined in vegetation zones at the drier end of the moisture gradient, but increased in grass and sedge-dominated zones at the wetter end of the gradient, at the expense of forb, grass, and sedge layers.