The High-Elevation Carbonate Mountains ecoregion includes a series of mountain ranges composed of limestone, dolomite, quartzite, and conglomerate in east-central Nevada. These mountains are in the zone of summer rain, although much of the precipitation percolates through the porous rock to reemerge at lower elevations as springs. Still, these carbonate-dominated mountains support a wider variety of conifers, such as white fir, Douglas-fir, and Engelmann spruce, and a greater diversity of understory species than other ranges in Nevada at similar elevations. Bristlecone pines have their widest distribution on carbonate substrates above elevation. Conditions do not favor alpine tundra, however; alpine plants are more limited than on the nearby granitic High Elevation Ruby Mountains.