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Comprehensive Description ( anglais )

fourni par Smithsonian Contributions to Botany
Entandrophragma angolense (Welwitsch) A. C. DeCandolle

Standard trade name: Gedu nohor

Local names: Edinam (Ghana), Gedu lohor, Gedunoha (Nigeria), Tiama (France and Ivory Coast.)

A deciduous forest tree growing to 160 ft tall with a clean bole up to 80 ft in height, girth of 15 ft above buttresses; bark smooth, pale gray-brown with pinkish or rusty orange patches; leaves alternate, exstipulate, paripinnate; inflorescence a large, lax panicle; flowers small, greenish white, scented.

GENERAL DESCRIPTION.—The heartwood is typically dull reddish brown and the light colored sapwood is about 4 in wide. Gedu nohor is of plain appearance compared to sapele but very similar to the African mahoganies. It is medium hard and medium heavy, varying in weight from 32–36 lb/ft3 (average about 34 lb/ft3) when seasoned and about 54 lb/ft3 green. The surface is lustrous. It has no distinct odor or taste.

SEASONING.—Gedu nohor seasons fairly rapidly with a tendency to distort. The British Forest Products Laboratory kiln schedule A is recommended (FPRL, 1956).

DURABILITY.—The wood is moderately durable. Damage by ambrosia beetles is occasionally present. It has been recorded in Nigeria as moderately resistant to preservative treatment.

WORKING QUALITIES.—Works fairly easily with machine and hand tools. It planes and turns well, but may have a tendency to pick-up on the quarter. It bores and takes nails and screws well. Gluing is satisfactory.

USES.—Its uses are similar to sapele. Being a decorative timber, it is used for paneling, interior and decorative work, furniture and superior joinery.

XYLEM ANATOMY.—Growth rings absent. Wood diffuse-porous rarely. Vessels: solitary or in radially oriented groups of 2 or 3, pores circular in outline; average pore diameter 82μm, range 45μm–110μm; average vessel element length 556μm, range, 400μm–900μm; vessel wall thickness 4μm; perforation plates not seen; vessel element end wall inclination transverse; intervascular pitting alternate, pits ca. 1.25μm. Imperforate tracheary elements: septate fiber tracheids with dark amorphous substance in some; average length 1798μm, range 1375μm–2225μm; pits moderately abundant, only on radial walls, slits extending beyond pit boundary. Vascular rays: heterogeneous, multiseriate (only 1 uniseriate ray seen), 3 or 4 cells wide, 20 to 39 cells high including tails, which are 1 or 2 cells in length. Axial parenchyma: apotracheal, bands 2 or 3 cells wide; also paratracheal, vasicentric and somewhat aliform.
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citation bibliographique
Ayensu, Edward S. and Bentum, Albert. 1974. "Commercial Timbers of West Africa." Smithsonian Contributions to Botany. 1-69. https://doi.org/10.5479/si.0081024X.14

Entandrophragma angolense ( anglais )

fourni par wikipedia EN

Entandrophragma angolense, called the tiama, is a tree species with alternate, pinnately compound leaves that are clustered at the ends of branches. It is within the family Meliaceae and has a wide distribution area, occurring in moist semi-deciduous and evergreen forest regions of Tropical Africa from Sierra Leone to Uganda.[1]

Harvesting for timber has caused the species to become vulnerable in certain countries.[1]

Taxonomy

Entandrophragma angolense was first indicated as belonging to the Swietenia family but upon a revision in 1894 by de Candolle, the species was transferred to a new genus Entandrophragma.[2] In 2021, up to 10 taxa are placed as synonyms of the species in two database.[3][4]

Description

The tree can grow to a height of 60 meters and reach a diameter of 200 cm, its base often has developed buttresses that can reach a height of 6 meters, and extending as surface roots, the trunk is branchless for up to 30 meters.[5] The grey-brown bark tends to be thin and smooth with irregular flaking in small and large pieces leaving concave or mussel-shell shaped scars, slash is pink to reddish.[1] Leaves are paripinnately compound, up to 50 cm long and tufted at the ends of branches, 4-11 pairs of opposite leaflets per pinnae, petiole is up to 18 cm long.[6][1] Leaf-blade outline is commonly oblong to obovate, 3.5–12 cm long and 2–4 cm wide, upper surface is dark green and coriaceous. Flowers are in dense panicles, clustered at the end of branches, petal is greenish white in color, flowering period is between November and February.[1] Fruits is a large pendulous capsule, up to 22 cm long.[5][6]

Distribution

The species distribution is wide spread in tropical Africa, its native range is within the evergreen and semi-deciduous forest zones of West, Central and East Africa.[6] In Eastern Africa, majorly Kenya and Uganda, occurrence is of a lower density than in Central and West Africa.[7]

Chemistry

Chemical compounds including the limonoids: 7α- acetoxydihydronomilin, 7α- obacunylacetate and Methyl angolensate have been isolated from methanol extracts of the stem bark of the species.[8][9]

Uses

Timber traded as Tiama mahogany, White tiama or Genu Nohur is used for cabinet making, furniture and interior and exterior joinery.[1] In traditional medicine, extracts of the stem bark is used to treat various gastrointestinal afflictions and a decoction is consumed to treat fever.[10]

References

  1. ^ a b c d e f Timbers. D. Louppe, A. A. Oteng-Amoako, M. Brink, Plant Resources of Tropical Africa. Wageningen: PROTA Foundation. 2008. p. 235. ISBN 978-90-5782-209-4. OCLC 299747129.{{cite book}}: CS1 maint: others (link)
  2. ^ Monthe, Franck K.; Duminil, Jérôme; Kasongo Yakusu, Emmanuel; Beeckman, Hans; Bourland, Nils; Doucet, Jean-Louis; Sosef, Marc S. M.; Hardy, Olivier J. (2018). "The African timber tree Entandrophragma congoense (Pierre ex De Wild.) A.Chev. is morphologically and genetically distinct from Entandrophragma angolense (Welw.) C.DC". Tree Genetics & Genomes. 14 (5): 66. doi:10.1007/s11295-018-1277-6. ISSN 1614-2942. S2CID 52046034.
  3. ^ "Entandrophragma angolense (Welw.) Panshin | Plants of the World Online | Kew Science". Plants of the World Online. Retrieved 2021-10-18.
  4. ^ "Entandrophragma angolense (Welw.) C.DC". www.gbif.org. Retrieved 2021-10-18.
  5. ^ a b Voorhoeve, A. G. (1979). Liberian high forest trees : a systematic botanical study of the 75 most important or frequent high forest trees, with reference to numerous related species (2nd impr ed.). Wageningen: Pudoc. ISBN 90-220-0701-4. OCLC 63303450.
  6. ^ a b c Kasongo Yakusu, Emmanuel; Monthe, Franck; Bourland, Nils; Hardy, Olivier J.; Loupe, Dominique; Bola Mbele Lokanda, Félicien; Hubau, Wannes; Kahindo Muhongya, Jean-Marie; Van den Bulcke, Jan; Van Acker, Joris; Beeckman, Hans (2021). "Entandrophragma : taxonomy and ecology of a genus of African tree species with economic importance : a review". Biotechnologie Agronomie Société et Environnement. 5 (3): 140–153. hdl:1854/LU-8710779. ISSN 1370-6233.
  7. ^ Mbatudde, M.; Majaliwa, G.; Eilu, G.; Kakudidi, E.; Dalitz, H. (2013). "Potential distribution of vulnerable Entandrophragma angolense (Welw.) C. DC. (Meliaceae) in East Africa". African Journal of Ecology. 51 (3): 471–481. doi:10.1111/aje.12058.
  8. ^ Njar, V. C.; Adesanwo, J. K.; Raji, Y. (1995). "Methyl angolensate: the antiulcer agent of the stem bark of Entandrophragma angolense". Planta Medica. 61 (1): 91–92. doi:10.1055/s-2006-958015. ISSN 0032-0943. PMID 7701005.
  9. ^ Bickiia, J; Tchouyab, Grf; Tchouankeub, Jc; Tsamo, E (2008-09-22). "The antiplasmodial agents of the stem bark of Entandrophragma angolense (Meliaceae)". African Journal of Traditional, Complementary and Alternative Medicines. 4 (2): 135–139. doi:10.4314/ajtcam.v4i2.31188. ISSN 0189-6016.
  10. ^ Orisadipe, Abayomi; Amos, Samson; Adesomoju, Akinbobola; Binda, Lucy; Emeje, Martins; Okogun, Joseph; Wambebe, Charles; Gamaniel, Karniyus (2001). "Spasmolytic Activity of Methyl Angolensate. A Triterpenoid Isolated from Entandrophragma angolense". Biological and Pharmaceutical Bulletin. 24 (4): 364–367. doi:10.1248/bpb.24.364. ISSN 0918-6158. PMID 11305596.
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Entandrophragma angolense: Brief Summary ( anglais )

fourni par wikipedia EN

Entandrophragma angolense, called the tiama, is a tree species with alternate, pinnately compound leaves that are clustered at the ends of branches. It is within the family Meliaceae and has a wide distribution area, occurring in moist semi-deciduous and evergreen forest regions of Tropical Africa from Sierra Leone to Uganda.

Harvesting for timber has caused the species to become vulnerable in certain countries.

licence
cc-by-sa-3.0
droit d’auteur
Wikipedia authors and editors
original
visiter la source
site partenaire
wikipedia EN