Jarrah forest is tall open forest

Forest

A forest, also referred to as a wood or the woods, is an area with a high density of trees. As with cities, depending where you are in the world, what is considered a forest may vary significantly in size and have various classification according to how and what of the forest is composed...

 in which the dominant overstory tree is Eucalyptus marginata (jarrah). The ecosystem occurs only in the Southwest Botanical Province of Western Australia

Western Australia

Western Australia is a state of Australia, occupying the entire western third of the Australian continent. It is bounded by the Indian Ocean to the north and west, the Great Australian Bight and Indian Ocean to the south, the Northern Territory to the north-east and South Australia to the south-east...

. It is most common in the biogeographic region named in consequence Jarrah Forest

Jarrah Forest

Jarrah Forest is an Interim Biogeographic Regionalisation for Australia region in Western Australia.-Location and description:The ecoregion stands on the 300m high Yilgarn block inland plateau and includes wooded valleys such as those of Western Australia's Murray River and the Helena River near...

.

Most jarrah forest contains at least one other co-dominant overstory tree; association with Corymbia calophylla

Corymbia calophylla

Corymbia calophylla is a bloodwood native to Western Australia. Common names include Marri and Port Gregory Gum, and a long standing usage has been Red Gum due to the red gum effusions often found on trunks.It is distinctive among bloodwoods for its very large buds and fruit Corymbia calophylla...

is especially common, and results in which is sometimes referred to as jarrah-marri forest.

Considerable amount of research delineates Northern, Central and Southern Jarrah forest which relates to rainfall, geology and ecosystem variance.