The biome characterized by permafrost and low-growing plants such as mosses and lichens is the tundra. Tundra environments are cold, largely treeless landscapes where short growing seasons and frozen subsoil limit plant growth.
The word covers several related environments: Arctic tundra around the far north, alpine tundra above the tree line in mountains, and Antarctic tundra in parts of the Southern Hemisphere. Plants stay close to the ground, where they are less exposed to wind and can take advantage of the thin layer of soil that thaws during summer. Other common plants include sedges, grasses, dwarf shrubs and flowering herbs.
Permafrost is a defining feature of much Arctic tundra, but it is not present in exactly the same form everywhere tundra occurs. Alpine tundra, for example, is shaped mainly by altitude, cold and poor soils. A frequent mix-up is taiga, the neighbouring northern biome: taiga supports extensive coniferous forests, while tundra generally lies beyond the tree line.