Nearctic Montane Mixed Conifer Forest - Code: Ne1D

A widely distributed and highly variable habitat of w. North America, Nearctic montane mixed-conifer forest is the quintessential western forest of towering conifers, with the smell of vanilla coming off sun-warmed Ponderosa Pine and the distant drumming of woodpeckers. Anyone who has spent time hiking in the mountains of the w. Nearctic region has enjoyed these vast and inviting forests. 
The canopy here is fairly open at the lowest elevations where it grades into Ponderosa Pine Forest and becomes more closed farther upslope. While the height of the canopy is generally 65–120 ft. (20–35m), some of the larger trees can reach heights over 200 ft. (60m). The Rocky Mountain Mixed Conifer Forest subtype tends to be shorter overall and lacks the gargantuan trees found in the Sierra Nevada - Columbia Plateau Mixed Conifer Forest subtype.  With a sparse mid-story and a variable shrub layer, these forests are quite open and easily traversed, making them a pleasant place for hiking and wildlife observation.
One of the hallmarks of the montane mixed-conifer forest is the diversity of conifer species present. Douglas-fir (Pseudotsuga menzeisii) and Ponderosa Pine (Pinus ponderosa) are the two most widespread components of the canopy, found at all but the lowest elevations. In the Rocky Mountain Mixed Conifer Forest subtype, other important co-dominant trees are Lodgepole Pine (Pinus contorta), Grand Fir (Abies grandis), White Fir (Abies concolor), Blue Spruce (Picea pungens), and Western Redcedar (Thuja plicata). The Sierra Nevada - Columbia Plateau Mixed Conifer Forest subtype has a different set of co-dominant trees, with Sugar Pine (Pinus lamertiana), Jeffrey Pine (Pinus jefferyi), Western White Pine (Pinus monticolla), Incense Cedar (Calocedrus decurrens), and White Fir all occurring widely. The Giant Sequoia (Sequoiadendron giganteum) is found in the montane mixed-conifer forests of the c. Sierra Nevada. This most massive of trees changes the structure of the forests, as little understory and large canopy gaps surround these living giants. 
In Nearctic Montane Mixed-conifer forest, the mid-story is typically very sparse and comprises smaller individuals of the dominant tree types. Depending on frequency of fire and canopy density, the shrub layer can be absent to dense. The shrub layer is highly diverse over this habitat’s range, with well over 100 species represented. Shrubs typically found throughout the range include Big Sagebrush (Artemesia tridentata), manzanitas (Arctostaphylos spp.), ceanothuses (Ceanothus spp.), ninebarks (Physocarpus spp.), dogwoods (Cornus spp.), Huckleberry Oak (Quercus vaccinnifolia), and Gambel Oak (Q. gambellii). More closed canopy stands can completely lack herbaceous ground cover, with little but fallen conifer needles covering the forest floor.
The high variability in species composition and structure also means there is a highly variable fire regime present. Frequent low-intensity fires were more common in the Sierra Nevada, while the Rocky Mountains experienced a full spectrum of fire regimes. Fire suppression has led to denser forests and more shade tolerant species like White Fir. This also tends to result in high intensity fires when they do occur.