 High in the mountains, but below the timber line, exist the subalpine forest community. Spruce and fir trees often dominate these areas because they can tolerate the cool temperatures and require relatively large amounts of water found at these elevations. This restricts these trees to the cool, moist environments found at these elevations. When a fire or other large disturbance occurs, these spruce and fir trees will often be replaced by pioneering species such as lodgepole pine and aspens. As time goes on, shade tolerant species such as the spruce and fir eventually come back in and in the absence of more disturbances may eventually again dominate the site. Sometimes these subalpine forest communities are interspersed with meadows. One of the reasons these meadows probably exist is because of differences in the soil which favor grasses and forbs over large trees. These subalpine forest communities provide many resources for wildlife and humans alike. From the University of Wyoming Cooperative Extension Service, I'm Barton Stam.