About 26% of Sudan is covered by forests. About 61.6 million ha (152.2 million acres) of Sudan are covered by forests, half of which are dense stands of trees, mostly in the south. Sudan supplies over 80% of the world's needs of gum arabic, extracted from the acacia. Production of roundwood was estimated at 18.8 million cu m (663.6 million cu ft) in 2000, with 88% used as fuel. Timber production, apart from cutting for local village needs, is confined to forests lying within reach of navigable rivers or areas served by roads and railways. The Ministry of Agriculture and Natural Resources maintains forests, administers public preserves, and operates sawmills. Around 11% of Sudan's forests are in protected areas.