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Subalpine Spruce-Fir Forest

This cool highland forest is dominated by two tree species: Englemann Spruce and Corkbark Fir (a southern species variant of the more common Subalpine Fir). Quaking aspen is also abundant on sunnier exposures and near the forest's lower elevational limit. The spruce-fir forest is the shadiest, wettest, and densest of the forest types found in the state. The abundance of shade and more annual snowfall leads to lingering snowpacks keeping the forest floor moist much of the year. At these high elevations (10,000 feet to 11,500 feet) annual precipitation is fairly high, generally from 30 to 40 inches a year. Much of this falls as snow during the cooler months, but a significant portion falls as heavy rains during the summer monsoon season. Here, the spruce and fir trees must adapt to the strong winds and cold temperatures so common throughout much of the year. The branches of the trees are brittle, so they grow close together to buffer the wind, and both species have narrow, pointed crowns, which help shed snow.

The subalpine forest extends from the upper part of the continuous Spruce-Fir forest to timberline, the elevation at which trees can no longer grow. This is a transition zone between Alpine Tundra higher up and the forest below. It is characterized by tree islands and dwarfed and wind-beaten trees. Strong winter winds blast trees with ice preventing growth above winter snowbanks (which buffet wind) and thus many form shrubby mats or are only a few feet tall. An important species accompanying spruce and fir in the cold subalpine environment atop the San Francisco Peaks near Flagstaff is the Bristlecone Pine. Though abundant on exposed sites near timberline, Bristlecone Pine also forms nearly pure forests on warmer sites such as south-facing slopes and in dry meadows This pine is believed to be the longest living organism on the planet with some trees in Nevada living nearly 5000 years!

Common inhabitants include mostly small mammals and birds, although mule deer and elk frequent open areas such as the large grassy meadows found in the White Mountains. Often the red squirrel can be heard chattering among the spruce and fir, while the beautiful song of the hermit's thrush is common during the summer months. The large gray, white, and black clark's nutcracker is a curious bird that often visits campsites in search of food scraps. Mountain chickadee, blue grouse, pine grosbeak, and the warbling vireo are other common birds found in these high forests.


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