The growing and felling of trees generates products that are chiefly desired as roundwood, measured in cubic metres of solid volume without bark; wood pulp; newsprint; and paper and paper board. The instability of supplies and prices for these products is a function of forest vulnerability to over-cutting, fire and pests, and under-planting to compensate for these.
Some 32% as the world land area is classified as forest land. Asia and Europe have 1.1 hectares per capita of population, South America has 4.9, USSR 3.8, and North America, 3.4 hectares. In volume the world's standing timber is estimated at over 235 milliard (billion) cubic metres. The annual harvest is about 2 milliard; just under 7%. Fuel wood consumption accounts for nearly half; and industry uses over 1 milliard cubic metres annually.