Cryic Xeric Mountain Slopes and Plateaus (Subalpine fir Cool Dry Grass)

Description

The stand dynamics depend on whether low intensity fires occur frequently to keep an open stand with older mature Douglas-fir, ponderosa pine, and larch. Scattered subalpine fir, lodgepole pine, and Engelmann spruce may be present. In this condition it looks similar to the Douglas-fir and pinegrass ecological site. If there is long low intensity fire intervals overstory and understory fuel loads buildup a stand replacing fire can revert site back to a grass and shrub site with a lodgepole pine the main regenerating tree species.

In low intensity fires Douglas-fir remains the dominant overstory with some ponderosa pine and larch. This is typical on the pinegrass and pinegrass/Oregon boxleaf boxwood sites. On the Oregon boxleaf boxwood site there is greater tree stocking and mixed severity fires and stand replacing fires are normal. Here there is a mixed forest of Douglas-fir, Engelmann spruce, Western white pine, ponderosa pine, and quaking aspen. On both scenarios subalpine fir is the climax species and is the main overstory and understory component if long fire intervals exist. This seldom occurs. Pinegrass is the dominant herb in the Pinegrass sites and shrubs like pachistima, spirea, serviceberry, scouler willow, rose, and big huckleberry are dominant over pinegrass in the pinegrass/Oregon boxleaf boxwood and Oregon boxleaf boxwood sites.

Submodel