West Rock Ridge hosts a combination of microclimates unusual in New England. Dry, hot upper ridges support oak savannas, often dominated by chestnut oak and a variety of understory grasses and ferns. Eastern red cedar, a dry-loving species, clings to the barren edges of cliffs. Lower eastern slopes tend to support oak-hickory forest species common in the surrounding lowlands. Narrow ravines support eastern hemlock that block sunlight, creating damp, cooler growing conditions with associated cooler climate plant species. These hemlocks have suffered from infestation by the hemlock woolly adelgid. Talus slopes are especially rich in nutrients and support a number of calcium-loving plants uncommon in eastern Connecticut. Because the ridge generates such varied terrain, it is the home of several plant and animal species that are state-listed or globally rare.