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Dalbergia sissoo Roxb. |
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Leguminosae |
Author: Le Houérou |
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Indian rosewood, Sissoo (Bengali) Deciduous tree reaching 30 m in height under favourable environmental conditions, with a bole diameter up to 80 cm. The bole may be somewhat twisted in isolated trees. The bark is grey 10-15 mm thick, with transverse fissures. Leaves are alternate, imparipinnate, 15 cm long bearing 3-5 petiolated, more or less acuminate leaflets alternately inserted in zig-zag on a 10-15 cm long rachis. Leaves are shed every year after having turned to a brownish hue. Flowers : Inflorescence in axillary panicles 5-10 cm long., erect and much shorter than the leaves. The filaments of the stamina are connate in a tube split in its upper part (characteristic of the genus). Fruits : pods are slender, light brown, oblong, flat, thin, 5-10 cm long x 9-13 mm wide, with a strongly cuneiform, stipulated base, containing 1-5 tiny seeds. Seeds are 7-9 mm long, compressed, flattened, bean-shaped, sometimes germinating readily in the pod. In its native habitat it behaves as a riverine species, growing up to 1500 m of elevation in the Himalaya foothills. Withstands occasional sub-freezing to light freezing temperatures. In its native habitat precipitation is 500-2000 mm MAR under a monsoon rainfall regime with a 4-5 month annual dry season. Below 800 mm MAR irrigation or the presence of a shallow water table is mandatory. In Niger under 570 mm of MAR plus 270 mm of irrigation the growth was similar to that of Eucalyptus camaldulensis, the fastest grower under such conditions. Soil requirements are very broad from sandy to clay soils and gravelly substrates, moderately tolerant to salinity up to 4 mS / cm CE. And to alkalinity, up to an ESP of 20 %. Sensitive, however, to flooding and water logging. Water logging brings about root-rot and damage from many fungi and nematodes. Best on humid well drained soils. The tree is native to Bangladesh. It originates in the foothills of the Himalaya in Pakistan, Nepal, India and Bangladesh ; it has been introduced into irrigated plantations in various parts of India, Pakistan and Africa. Propagation is easy, either by seeds, cuttings or suckering, the tree coppices and suckers profusely and is amenable to pruning, trimming and thinning. Seedlings and young trees are demanding in light but sensitive to wild fires. Wood quality is high (rose wood), the heartwood is dark golden brown, oily and heavy (d = 0.7-0.8) very durable and very resistant to termites, its caloric value is high 4,900 and 5,200 k cal / kg DM for sapwood and heartwood respectively. The oil from the wood (ca 5 %) is stable at high temperatures hence used for lubricating heavy machinery [like the Jojoba (Simmondsia) wax]. Leaves are good fodder with 13-21 % CP on the DM for old and young leaves respectively. The tree is very effective in controlling gully erosion. Agroforestry : D. sissoo is utilized in combination with a variety of crops, and as a shade tree for cash crops such as tea. It is also often utilized in urban forestry, in the city of Cairo, for one. Also used to produce timber under irrigation with waste water and effluents. D. sissoo is also appreciated by bees and the source of a variety of medicinal products. |