Sizable tree stands found in the southern regions are not fully exploited. The principal forest product is gum arabic, which is extracted from wild acacia trees that grow in the south. Until 1972, private traders collected and exported the gum; since 1972, it has officially been a monopoly of the state trading company, Société Nationale d'Importation et d'Exportation (SONIMEX). Nevertheless, much gum continues to be smuggled across the borders, particularly to Senegal. Roundwood removals were estimated at 1,434 cu m (50,620 cu ft) in 2000, 99% for fuel.