A tundra is a type of ecosystem where the climate is highly stressed.  It is usually very difficult for any living organism to survive in a tundra.

In order for a tundra to exist, the conditions must be right.  The moisture level is one of the most important environmental factors affecting the tundra area.

The Arctic Tundra.  Photo Credit: ClickART Image Pak.

Meadow areas with a large amount of moisture are often very grassy.  Drier areas are instead dominated by lichens and cushion plants.  Mesic areas consist mainly of herbaceous species and dwarf shrubs.

Tundra occurs only in a few places on the planet.  It is present in two forms: latitudinal and altitudinal.

In both the Arctic and the Antarctic, large latitudinal tundra areas can be found.  These environments are very cold, and the growing season is very short - the perfect conditions for the presence of tundra.

Altitudinal tundra occurs in other places.  This form of tundra is common on mountain tops.  The temperature here is usually very cold, so even a slightly longer growing season fails to permit most living things to survive.