Rivers and streams provide essential habitat for amphibian species such as the Northern dusky. Northern spring, and Northern two-lined salamanders. Reptiles which also utilize these riparian habitats are the Eastern milk snake, wood turtle, and Eastern garter snake. Relationships between U.S. Forest Service Timbered Community Types and other plant classification systems used in the Northeast. 1 1 I Residents of lakes and ponds in northeastern forests include the spotted turtle, Northern water snake, red-spotted newt, bullfrog and greenfrog. Other species, such as the wood frog, Northern spring peeper and spotted salamander require these wetlands for reproduction but may not be found in them at other times of the year. Home Range-The area traversed by any individual animal during its normal life. Individuals, pairs, or family groups of animals commonly restrict their activities to a definite home range. Krummholz Zone-The transition zone from subalpine forest to alpine tundra characterized by dwarfed, deformed, wind-sheared trees. Mature Stands-Areas covered by trees of small sawtimber size-larger than 9 in (22.9 cm) dbh if conifers, and 11 in (27.9 cm) dbh if hardwoods. Competition between trees has eliminated some overtopped or diseased individuals. Shade tolerant species such as beech, hemlock, and sugar maple are common in such stands. Very few large trees (14 in, 35.6 cm, or more dbh) or snags are present in such stands, and dense shade prevents understory development, although some understory plants exist. Nonvegetative, Rock, Sand, Mud, etc.-Land components which do not conform to the definitions for other non-timbered community types. Generally has a geologic origin, but may include man-made habitats such as gravel pits, quarries, buildings, human debris, and other structures. Old Growth-Areas covered by trees which are on the average larger than 14 in (35 cm) dbh with diseased and damaged trees becoming noticeable as they approach pathological (natural) rotation. Snags for cavity nesters become apparent; mortality and windfall create small clearings that soon become pockets of regenerating growth. Opening-Land on which grasses, herbs, and shrubs dominate the vegetation, including but not limited to "nonforest" and "unproductive forest." Openings may include some trees. Opening-Undifferentiated-A land area having high solar illumination at the ground level. An opening can be dominated by land features such as water or rock or by vegetation features such as grasses, forbs, or shrubs. Orchard-Areas one-half acre (0.2 ha) or larger where fruit trees-usually apple-are abundant. Groups of trees can be classified as "orchard" if they occur in clumps of five or more trees or where there are more than 10 trees per acre (0.4 ha). At this tree density, the fruits produced constitute a significant food source for many wildlife species. Pasture-Grazing land under relatively intensive management, usually supporting introduced forage species, and receiving periodic cultural treatment such as tillage, fertilization, mowi...
