The word tundra derives from the Finnish word for barren or treeless land. The tundra is the simplest biome in terms of species composition and food chains.
Vegetation: lichens, mosses, sedges, perennial forbs, and dwarfed shrubs, (often heaths, but also birches and willows).
Growthforms: typical are ground-hugging and other warmth-preserving forms including:
tussock-forming graminoids
mats or cushion plants, often evergreen members of the heath family
rosettes
dwarf shrubs, some of which are deciduous in habit
Climate: The high latitude conditions of Koeppen's ET climate type that impact life in this biome include
extremely short growing season (6 to 10 weeks)
long, cold, dark winters (6 to 10 months with mean monthly temperatures below 32° F or 0° C.)
low precipitation (less than five inches/year) coupled with strong, drying winds. Snowfall is actually advantageous to plant and animal life as it provides an insulating layer on the ground surface.
Edaphic controls: Permafrost, not cold temperatures per se, is generally believed to be what prevents tree growth. Furthermore, freeze-thaw activity, a thin active layer, and solifluction during the warmer months contribute to strong controls on vegetation patterns and create a mosaic of microhabitats and plant communities.
Soil: No true soil is developed in this biome due to the edaphic factors mentioned above.
Fauna: Strategies evolved to withstand the harsh conditions of the tundra can be divided among those species that are resident and those that are migratory.
Animals of the tundra: small number of bird (e.g., ptarmigan) mammals (e.g., muskox, arctic hare, arctic fox, musk ox) reside year-round on the tundra
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