Most tundras are covered by snow more than half the year. Long cold winters and short cold summers prevent the growth of trees, but mosses, lichens, grasses and sedges do grow there. Many kinds of animals also live upon the tundra. The yellow portions of this map are areas of the world which have been classified as Tundra. There are two kinds of tundras, arctic and alpine.
Most tundras are lowlands with many lakes, but some also have mountains.
Geese in migratory flight. In spring, tundras come to life. Geese, terns and other birds fly north to nest. The tundra plants grow rapidly and cover the ground with bright flowers. Caribou, reindeer and musk oxen graze on these plants and wolves prey on the grazing animals.