Key to Cultivated Tsuga Species - Includes revised species concepts and cultivar groups. Tsuga mertensiana (Mountain Hemlock) - Describes physical characteristics and habitat. Provides photos of entire tree, leaves, cone, and bark. Tsuga heterophylla (Western Hemlock) - Features photos of entire tree, leaves, cones, and bark. Describes physical characteristics, habitat, and human uses. Tsuga caroliniana - Distribution and occurrence, value and use, characteristics, and fire ecology. Tsuga canadensis - Information on distribution and occurrence, value and use, characteristics, and fire ecology. Tsuga mertensiana - Distribution and occurrence, value and use, characteristics, and fire ecology. Tsuga canadensis: Eastern Hemlock - Tree identification fact sheet with photos of the leaf, flower, fruit, twig, bark and form. Tsuga caroliniana: Carolina Hemlock - Tree identification fact sheet with photos of the leaf, flower, fruit, twig, bark and form. Tsuga heterophylla: Western Hemlock. - Tree identification fact sheet with photos of the leaf, flower, fruit, twig, bark and form. Tsuga mertensiana: Mountain Hemlock - Tree identification fact sheet with photos of the leaf, flower, fruit, twig, bark and form. Tsuga - Description of the genus and its 8 species.