forest

This image shows the marked changes to the landscape after an area of forest has been completely cut down.

Coniferous trees surround a glacial lake, among the Dolomite mountains in Italy. Forests in mountainous areas are often coniferous, because this type of evergreen tree is well suited to the soil, weather, and other environmental factors found at high altitudes.

In many mountain areas there are large areas of coniferous forest. This is because temperatures are low, and the soil thin and acidic. Evergreen trees are also able to photosynthesize at low temperatures, and their conical shape helps them to get rid of snow during winter. Their wide roots also help them to survive rocking by high winds, and they are able to cling to steep slopes such as the one pictured.

Timber extraction in a Russian forest. Large swathes of mixed and deciduous forest have been cleared to make way for agriculture, and to supply pulp and lumber mills.

River running through forest, Costa Rica. Timber is a diminishing resource in Costa Rica. Large swathes of forest have been destroyed to clear land for growing crops or grazing animals. There are still some reserves of tropical hardwood and many of these have protected status.

Area where trees have grown naturally for centuries, instead of being logged at maturity (about 150–200 years). A natural, or old-growth, forest has a multistorey canopy and includes young and very old trees (this gives the canopy its range of heights). There are also fallen trees contributing to the very complex ecosystem, which may support more than 150 species of mammals and many thousands of species of insects. Globally forest is estimated to have covered around 68 million sq km/26.25 million sq mi during prehistoric times. By the late 1990s this is believed to have been reduced by half to 34.1 million sq km/13.2 million sq mi.

The Pacific forest of the west coast of North America is one of the few remaining old-growth forests in the temperate zone. It consists mainly of conifers and is threatened by logging – less than 10% of the original forest remains.

Forest (died c. 1446)

English composer, possibly the John Forest who was canon and later dean of Wells, dying there in 1446. His motet Qualis est dilectus tuus was included (together with the beginning of Ascendit Christus, ascribed to John Dunstable in a continental manuscript) among the latest additions to the Old Hall manuscript. Other sacred music survives in continental sources.