Prota 7(2): Timbers/Bois d’œuvre 2
Char. gen. pl., ed. 1: 34 (1775).
2n = 32
Small-leaved mangrove (En). Bois matelot (Fr). Kilalamba kike (Sw).
Origin and geographic distribution
Pemphis acidula is found along the east coast of Africa from Somalia to Mozambique and on the Indian Ocean islands. It is further found on shores of tropical Asia and Australia, and on islands of the Pacific Ocean.
The hard and durable wood of Pemphis acidula is used for house posts, fence posts, tool handles, walking-sticks, domestic implements, turnery, anchors, boat nails and pestles. It is also used for firewood and charcoal production. Along the East African coast the bark has been used for tanning.
In Asia Pemphis acidula is occasionally planted as an ornamental, whereas the acid tasting leaves are eaten raw or boiled as a vegetable. In Vanuatu a filtered infusion of the bark is used as an abortifacient, and in Indonesia the bark is used to treat stomatitis.
Production and international trade
Because of the small size and the poor form of the bole of Pemphis acidula, as well as its limited supply, the use of the wood is on a small and local scale only. There is significant trade in seeds and live plants, especially in Asia for bonsai.
The heartwood of Pemphis acidul a is reddish brown to dark reddish brown, turning dark brown upon exposure, and is clearly differentiated from the pale, about 1 cm wide sapwood. The grain is interlocked, texture very fine. The wood is lustrous.
The wood is very heavy, with a density of 1100–1210 kg/m³ at 15% moisture content. It air dries well with little checking and warping. The rates of shrinkage upon air drying are moderate, from green to oven dry 5.4% radial and 8.5% tangential for wood from the Philippines. The wood is very hard and very strong. It is very difficult to work, but with care it takes a high finish. It is very durable, being resistant to dry-wood termite and Lyctus attacks.
The bark contains 19–43% tannin. In-vitro tests of the bark showed an increased activity on the amplitude and frequency of uterine contractions, which confirms the traditional use in Vanuata as an abortifacient. Bark extracts were found to have antibacterial, antioxidant and topoisomerase I inhibitor activities. Four galloyl flavonol glycosides with antioxidant activity have been isolated from leaf extracts.
Shrub to small tree up to 11 m tall; bole usually gnarled and much branched; bark surface dark grey, rough, reticulately flaking; twigs angular, densely hairy, nodes thickened with conspicuous leaf scars. Leaves opposite, simple and entire, sessile; stipules absent; blade obovate-oblanceolate to linear-lanceolate, 1–3.5 cm × 3–13 mm, cuneate at base, acute to obtuse at apex, leathery to fleshy, silky-haired, with only midrib distinct. Flowers solitary in leaf axils, bisexual, regular, 6-merous, heterostylous, sweet-scented; pedicel 5–13 mm long; calyx bell-shaped, greenish, 12-ribbed, hairy, with short lobes; petals inserted on calyx tube, c. 5 mm × 4 mm, white or pink, early caducous; stamens 12, inserted slightly below the middle of the calyx tube, 6 longer ones alternating with 6 shorter or all 12 nearly equal; ovary superior, globose, c. 2 mm long, 3-celled, style short or elongate. Fruit a globose capsule 4–6 mm long, purplish green, the upper part opening by a lid, many-seeded. Seeds c. 3 mm × 2 mm, with thick marginal wing, reddish.
Pemphis comprises a single species since Pemphis madagascariensis (Baker) Koehne, endemic to Madagascar, has been transferred to a separate genus Koehneria. The development of the tree corresponds to Attims’ architectural model, characterized by axes with continuous growth, differentiated into a monopodial trunk and equivalent branches. Flowers show heterodistyly, with stamens and styles in 2 length classes. Flowers are self-incompatible.
Pemphis acidula occurs at the landward side of mangroves. It may also be found exposed to the ocean, but then often partly sheltered by rocky shore, and it is occasionally even found below the high-water mark.
Genetic resources and breeding
Although Pemphis acidula is extremely widespread, it is uncommon along the east coast of mainland Africa, and the most important threat is to its habitat, i.e. mangrove vegetation, of which the area is rapidly diminishing.
Increase of the use of Pemphis acidula wood is unlikely in tropical Africa, but the wood will remain of interest for specialty uses.
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• Masuda, T., Iritani, K., Yonemori, S., Oyama, Y. & Takeda, Y., 2001. Isolation and antioxidant activity of galloyl flavonol glycosides from the seashore plant Pemphis acidula. Bioscience, Biotechnology and Biochemistry 65(6): 1302–1309.
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Correct citation of this article:
Bosch, C.H., 2010. Pemphis acidula J.R.Forst. & G.Forst. In: Lemmens, R.H.M.J., Louppe, D. & Oteng-Amoako, A.A. (Editors). Prota 7(2): Timbers/Bois d’œuvre 2. [CD-Rom]. PROTA, Wageningen, Netherlands.
obtained from TopTropicals
obtained from TopTropicals
obtained from TopTropicals
wood in transverse section
wood in tangential section
wood in radial section