People everywhere depend on trees for an enormous range of vital products and materials.
Trees provide the lumber to build homes and furniture, the telephone poles and railway ties that help bring society together, the pulp fibre for paper, the raw material for bowls and boxes, works of art, musical instruments, toys, and hundreds of other everyday articles. Many families derive a major part of their cash income from the sale of these products. As well, by far the most important source of energy in developing countries is neither petroleum nor hydroelectricity but wood used as fuel. Even trees that do not supply food themselves may help agriculture by contributing to soil conservation, by providing livestock fodder, or by giving shelter to herds and crops and creating favourable micro-climates. Forests regulate streamflows and precipitation, thus preventing soil erosion and providing habitats for enormously varied populations of plants and animals, whose importance is just beginning to be understood.