|
Pithecellobium dulce (Roxb.) Benth. |
  |
Leguminosae
|
Author: Le Houérou |
|
Madras thorn, Manilla tamarind and many other local names in various languages. Spiny tree up to 15-20 m high. Spreading habit with irregular branches, greyish bark becoming rough, then furrowed. Leaves are paripinnate with one single pair of pinnae and one single pair of leaflets per pinna, leaflets are 2.0-3.5 cm long x 1.0-1.5 cm wide. There are small thorns 2.0-15.0 mm long in axillary pairs inserted on each side of the leaves' pedicels. Thornless individuals do occur. Leaves are deciduous but foliage is persistent, as the new leaves appear while the old ones are being shed ; so that the tree looks like an evergreen. Flowers are disposed in small spherical glomerules of ca 1 cm in diameter, forming short axillary panicles of 5-30 cm in length. Flowers are white-greenish slightly fragrant 1.0-1.5 mm in diameter, with a hairy corolla, 50 thin stamina, connate in a tube at their basis, surrounded by the green calyx. Legumes are greenish-brown to red or pinkish, rather thin, 10-15 cm long x 1-2 cm wide. There are ca 10 seeds per pod ; pods are irregular in shape and flattened, set in a spirals of 1 to 3 whorls and strangled between the seeds (lomentaceous). Seeds are black and shiny ca 1 cm in diameter hanging in the pods by a red funicle. The pod is dehiscent on both sides. It has fair cold and heat tolerance. Rainfall requirements are broad, MAR varies from 400 to 1500 mm. Quite drought tolerant, as it can stand 4-5 months of dry season. Soil requirements are unassuming as the tree tolerates poor and shallow soils, wasteland and degraded environments, including brackish soils and some salinity. Originally from tropical and subtropical America (South West USA, North West Mexico, Central and Southern America), that has now become a pan-tropical species, like Leucaena leucocephala, Gliricidia sepium and Tamarindus indica. The tree is found up to 1,500 m of elevation in Mexico and East Africa. Pithecellobium has been successfully planted in the South Sahelian and North Sudanian ecozones, but not over large acreages. Pithecellobium is usually propagated by seeds or cuttings. It suckers well and responds positively to pollarding and to coppicing. Growth is moderately fast, and competition with grasses fairly successful, but without eliminating them. Wood is hard and lasting, but because of the irregular shape of the bole and branches, it is mainly used for making rough carpentry, posts and sleepers ; it is a poor, smoky firewood. Pods, leaves and twigs are good fodder for herbivores and the species is considered as a fodder tree, in the Rep. of Sudan, for instance. Crude protein content up to 29 % has been recorded in the foliage and 17.5 % crude fiber. Pithecellobium is often used for land rehabilitation, by reason of its soil hardiness and drought-tolerance; it is also used as shelter, wind-break and defensive live hedge. It is also often planted as a street tree and for other amenities. The pulp of the fruit, is white or red, very sweet and of a pleasant flavour as a human food (hence the scientific name meaning 'sweet monkey-ear' in Latin and Greek respectively); the large aril, represents 50 % of the fruit (seeds 25 %, husk 25 %) ; the edible seed and the aril are sweet with a chesnut flavour ; the fruit is eaten raw or for making sweet-sour drinks (like the tamarind). Pithecellobium also produces an edible gum reminiscent of gum arabic. Flowers are attractive to bees and procure a good quality honey. The bark is very high in tannins of the catechol type (up to 37 %), and is used for this in the tanning industry in the Philippines and India. Aubréville 1950 ; Dalziel 1955 ; Berhaut 1975 ; Burkill 1995 ; Baumer 1995 ; Dommergues et al. 1999. |