. Skalkaho timber sale environmental assessment . Forest reserves; Logging; Logging; Environmental impact statements; Harvesting. u.^—>^^ '.^^--^J^i^^j ?'''K''*'^'^^''^'y^. Existing Fire Hazard and History The most predominant historic fire frequencies in the project area occur on the warm, dry Douglas-fir and warm, dry Ponderosa Pine habitat types, which had a mean fire interval of around 5-25 years in presettlement stands. Fire was an important agent in controlling density and species composition. Low to moderate severity fires converted dense stands of pole-sized or larger trees to
. Skalkaho timber sale environmental assessment . Forest reserves; Logging; Logging; Environmental impact statements; Harvesting. u.^—>^^ '.^^--^J^i^^j ?'''K''*'^'^^''^'y^. Existing Fire Hazard and History The most predominant historic fire frequencies in the project area occur on the warm, dry Douglas-fir and warm, dry Ponderosa Pine habitat types, which had a mean fire interval of around 5-25 years in presettlement stands. Fire was an important agent in controlling density and species composition. Low to moderate severity fires converted dense stands of pole-sized or larger trees to a more open condition, and subsequent light burning maintained stands in a park-like state. Frequent low or moderate fires favored larch and ponderosa pine over Douglas-fir in stands where these species occurred. Severe fires probably occurred on dense, fuel-heavy sites and resulted in stand replacement. Stand replacement fires favored lodgepole pine on sites where this species was present (Fischer and Bradley, 1987). In the ponderosa pine dominated stands the fire frequency is expected to be on the shorter end of the range between fires and was typically a lower intensity event except in areas where fuels had built up or extreme weather conditions occurred. Currently, the risk of a stand replacing fire or a fire that would burn more intensely than expected under natural conditions historically on these two sections is moderate to high. With the near exclusion of fire in the 20*century, stand dynamics, succession, and fuel loadings have all changed. With increased fuel accumulations on the forest floor, stand densities, and amounts of ladder fuels (especially Douglas-fir in the understory) in these stands, fires burning today are much more likely to be more intense. These more intense fires tend to replace entire stands that would not have typically been replaced historically often times with negative effects of soil damage, species composition changes, difficulty regenerati
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