What makes a forest a forest?

Virtually all Europe’s forests are actively managed, with a high proportion certified for sustainable timber production.
© Scevenels/UNEP
The vast boreal forests of the northern hemisphere have relatively few species in them but hold immense stocks of carbon.
© LB Brubaker/NOAA
In China nearly 300,000 km2 of forest has been created since 2000, much of this by planting trees in previously unforested areas.
© Ariel Steiner/GNU-FDL
Southeast Asian rainforests may be the most diverse ecosystems on Earth. Huge areas are being cleared for cultivation of palm oil and other crops.
© Marco Schmidt/CC-2.5

The rainforests of New Guinea remain relatively little explored and yield a constant stream of previously unknown species.
© Lipton Sale/GNU-FDL
Protected areas such as Egmont National Park in New Zealand provide crucial refuges for forest ecosystems.
© NASA
Australia is the world’s driest continent. Many of its eucalyptus forests are adapted to fire and frequent drought.
© Arnaud Gaillard/CC-1.0
Around 90 per cent of Madagascar’s unique and often highly threatened species depend on forest, which now covers only around 20 per cent of the land area.
© Jialiang Gao/GNU-FDL

Mangroves are the only forests that grow in salt water, providing vital coastal defences and nursery areas for many fish species.
© UNEP/Topham
Tiny remnants of Atlantic coastal forest persist in southern Brazil, in close proximity to some of the largest conurbations on Earth.
© Specialist Stock
The Amazon Basin contains the largest expanse of primary forest in the world: more than 6 million km².
© M Watts/CC-2.0

The temperate rainforests of North America are a source of the cancer drug taxol, made from extracts of yew trees, including the Pacific yew Taxus brevifolia.
© Jason Hollinger/CC-2.0
Cork oak forests, the basis of a traditional cork-harvesting industry in Portugal and Spain, are home to the world’s most endangered cat, the Iberian lynx Lynx pardinus.
© Carsten Niehaus/GNU-FDL