Allernative uses

The benefits to be derived from the nitrogen-fixing ability of leguminous plants are well known and species of Prosopis are no exception. They are usually found growing in soils with poor nitrogen status where their leguminous nature allows them to thrive. Members of the genus have a variety of uses and, indeed, P. cineraria has been classed as a genuinely multipurpose tree (Leakey and Last, 1980) providing firewood, timber, fodder, soil improvement, shelterbelts, edible fruit, medicines, bee forage, sand dune stabilization and extractable tannins and edible gums.

The pods are an important source of human food. In the semi-desert regions of S. America, mature Prosopis pods are used to prepare a sweet, floury paste considered a valuable food, particularly for children. The sugary pulp from the pods can be fermented and distilled to produce ethyl alcohol. Green and ripe pods of P. cinerarare consumed in India. The green pods are used in curry dishes or are dried and preserved, while the pulp of mature pods is eaten by children (Harden and Zolfaghari, 1988).

The wood is highly valued, being compact, closegrained, heavy, and resistant to borers, termites and general decay. It is used for implement handles, walking sticks, floors, posts, barrels, cabinets and larger constructions. All species are used as firewood and Prosopis is renowned as an excellent, slow-burning charcoal (Allen and Allen, 1981; Habit et al., 1981; Booth and Wickens, 1988).

The bark of various species contains substantial quantities of mesquite gum, which resembles gum arable, has emulsifying properties and is an excellent mucilage. Tannins are also present in concentrations that justify commercial extraction (Allen and Allen, 1981).

Crane (1975) included Prosopis spp. amongst the very drought-tolerant, tropical plants in her classification of important world honey sources. The nectar gathered from these trees is purported to yield a honey of superior flavour (NAS, 1979), while the bark can be used to make beehives (Booth and Wickens, 1988).

In Africa, the wood of P. africana was traditionally credited with soporific properties (Dalziel, 1948), while the macerated leaves were thought to ensure male fertility (Uphof, 1968). Nearly all parts of the tree are used in local medicines (Booth and Wickens, 1988). Young roots are used as a diuretic and to treat dysentery, while the vapour from boiling them is used against bronchitis and to control vermin. The bark is used to make a mouthwash to alleviate toothache and an eyewash to treat opthalmia. Dried, powdered bark is used against leprosy, orchitis, rheumatism, dermatosis and fever and to heal wounds, while the leaves are used to treat head, eye, ear and tooth troubles, or as a bath for the treatment of migraine and vertigo. Broun and Massey (1929) reported that dried and crushed pods or fruit husks of P. africana were used as a fish poison.