Entandrophragma angolense

Entandrophragma angolense
Systematics
	Rosids
	Eurosiden II
Order :	Sapindales (Sapindales)
Family :	Mahogany (Meliaceae)
Genre :	Entandrophragma
Type :	Entandrophragma angolense
Scientific name
	Entandrophragma angolense
	( Welw. ) C.DC.

Entandrophragma angolense is a species ofthe mahogany family (Meliaceae). It is common in tropical Africa ( West and Central Africa ). There are several trade namesfor the wood of Entandrophragma angolense Tiama , gedu nohor , Kalungi and edinam . The trade abbreviation according to DIN EN 13556 for this type of wood is ENAN . Common names are in English Tiama mahogany , in French Tiama , acajou tiama and in Portuguese Kibaba da queta .

description

Appearance, bark and leaf

Entandrophragma angolense grows as a deciduous tree and reaches heights of 40 to 50, rarely up to 60 meters. The trunk, which is seldom cylindrical, often deformed, and mostly straight, with a chest height of 0.7 to 1.0 or up to 2.0 meters, is free of knots up to a height of 30, rarely up to 40 meters. The trunk is often supported by wide, blunt buttress roots that reach up to 6 meters high and often extend into above-ground roots. The initially almost smooth bark later forms up to 20 centimeters large, irregular scales, which at the end dissolve into fibers. The bark has a light grayish-brown to orange-brown on the outside and a pink-reddish color on the inside. The bark of the branches is bare and leaf scars and lenticels can be seen on it .

Arranged alternate clustered at the ends of the branches leaves are divided into petiole and leaf blade. The 8 to 18 centimeter long petiole is flattened or slightly furrowed and often somewhat winged at its base. The sheet rhachis is 6 to 30 centimeters long. The stalks of the leaflets are 1 to 6 inches long. In the paired pinnate leaf blade there are usually 14 to 20 (8 to 22) pinnate leaves arranged opposite to alternate. The leaflets with a length of 3.5 to mostly 7 to 28 centimeters and a width of 2 to mostly 3 to 8.5 centimeters oblong-obovate to oblong-elliptical with a wedge-shaped to almost rounded base and a short-pointed or somewhat hood-shaped upper end. The thin, leathery pinnate leaves are almost bare and have six to twelve lateral nerves on each side of the mostly hairy middle nerve. There are no stipules .

Inflorescence and flower

Entandrophragma angolense is dioecious separate sexes ( diocesan ). The lateral or terminal, strongly branched, short hairy to almost bald, paniculate inflorescence has a length of 30 to 40 centimeters. The flower stalk is 0.5 to 1.5 millimeters long.

The functionally unisexual flowers are radial symmetry and five-fold with a double flower envelope . In the flower buds, the twisted petals are much longer than the sepals. The five 0.5 to 1 millimeter long sepals are cupped up to about the middle and have short hairs on the edges. The five free, greenish-white, bald petals are elongated-elliptical with a length of 4 to 5 millimeters. The five-lobed, cushion-shaped disc surrounds the base of the ovary and forms a connection with the stamen with ten short ridges. There are two circles with five stamens each. The ten stamens are fused into an approximately 4 millimeter long cup-shaped stamen tube, which has an almost smooth edge. The ten anthers are located on the very short free sections of the stamens. The five carpels are fused to form a conical, upper, five- chamber ovary. In the male flowers, the anthers open with a longitudinal slit and there is a rudimentary ovary. Each ovary chamber contains several pendent anatropic ovules in two rows. In the female flowers, the smaller anthers do not open. The short, thick stylus protrudes slightly over the stamens. The disc-shaped scar does not completely block the entrance to the stamen.

Fruit and seeds

With a length of 15 to 20 centimeters and a diameter of 3.5 to 5 centimeters, the "cigar-shaped" capsule fruit turns brown to black when ripe. At the top, the capsule fruit opens with five woody valves. The one-sided winged seeds are about 1.5 centimeters long.

Occurrence

The wide original distribution area of Entandrophragma angolense extends from Guinea eastward to southern Sudan , Uganda and western Kenya and southward to the Democratic Republic of the Congo and Angola .

In West Africa, Entandrophragma angolense thrives most often in moist semi-evergreen forests, especially in areas with annual rainfall of 1600 to 1800 mm; it is also found in evergreen forests, but its abundance decreases sharply in areas with annual rainfall of over 2300 mm. Entandrophragma angolense thrives in East Africa in rainforests at lower to medium altitudes and sometimes also in gallery forests and thickets up to altitudes of 1,800 meters. It grows best in well-drained soils with good water holding capacity .

Hazard and protection

Entandrophragma angolense is considered an endangered species in Ghana and Uganda . In the Red List of endangered species of the IUCN is Entandrophragma angolense as "endangered" listed ( "vulnerable"). The species Entandrophragma angolense has not yet been listed as protected by the Washington Convention on the Protection of Species (CITES).

Taxonomy

It was first described in 1859 under the name ( Basionym ) Swietenia angolensis by Friedrich Welwitsch . The new combination to Entandrophragma angolense (Welw.) C.DC. was published in 1894 by Casimir Pyramus de Candolle in Bulletin de l'Herbier Boissier , 2, p. 582, plate 21. Other synonyms for Entandrophragma angolense (Welw.) C.DC. are: Entandrophragma congoense (Pierre ex De Wild.) A.Chev. , Leioptyx congoensis Pierre ex De Wild. , Entandrophragma pierrei A.Chev. , Entandrophragma septentrionale A.Chev. , Entandrophragma candolleanum De Wild. & T.Durand , Entandrophragma gregoireianum Staner , Entandrophragma macrophyllum A.Chev. , Entandrophragma leplaei Vermoesen , Entandrophragma rederi Harms , Entandrophragma platanoides Vermoesen .

Tiama

Wood

Tiama is considered exchange wood for exotic woods such as Khaya , Kosipo, Sapele , red meranti, Dibetou and even American mahogany . The sapwood can be over 10 centimeters wide. The color of the sapwood is whitish to reddish gray. The heartwood is mahogany-like and ranges from light red to reddish brown and sometimes has a purple tint. In a living tree, the heartwood and sapwood are difficult to distinguish from one another in terms of color. Only through drying and the associated darkening does the distinction between heartwood and sapwood become clear. The wood is not very resistant to fungal attack and is classified in durability class 3.

Structural features

Tiama: Microscopic view of the radial section

Tiama: microscopic view of the tangential section

The wood is porous. The vessels have a diameter of 110 to 200 micrometers and are therefore considered to be medium to large. The vessels contain red-brown, crystalline ingredients. Resin vessels are numerous. The medullary rays stand out as a mirror in the cut surfaces . The decorative line drawing at Tiama is the result of a pronounced, broad to narrowly striped alternating growth .

use

The wood is used in many ways. It can be used as solid wood or as a veneer , as well as indoors and outdoors. Thanks to its mahogany-like appearance, Tiama sliced veneer can be used in the furniture industry, for example as a furniture front. Rotary veneer is used to manufacture special plywood . As solid wood in interior construction, Tiama is suitable as parquet , stairs or as a furniture part. Tiama is also used as construction wood for medium-duty use indoors and outdoors as well as in ship and vehicle construction. The wood is used for turning and carving .

Machinability

Tiama wood is very easy to work with. It is good to slice and peel. The interlocking growth usually only leads to low roughness. The resin content can cause tools to dull and become sticky. All wood connections (for example nails, screws, glue) hold well. Drying should be carried out slowly as the wood tends to warp. The surface of the wood can also be processed well. These can be stained or painted. In order to maintain the attractive, decorative color of the wood, it should be treated with transparent or clear coating agents.

Mechanical properties

Parameter	value	unit
Bulk density	0.8 0.85 -0.9	g / cm³
Compressive strength	38- 48 -59	N / mm²
modulus of elasticity	8800-11300	N / mm²
Flexural strength	61- 78 -92	N / mm²
tensile strenght	1.6 2.1 -2.6	N / mm²

swell

AT Tchinda: Entandrophragma angolense (Welw.) C.DC. In: D. Louppe, AA Oteng-Amoako, M. Brink, (Editors): Prota 7, 1: Timbers / Bois d'œuvre 1. CD-Rom. PROTA, Wageningen, Netherlands, 2008: Online at PROTA4u (sections description and distribution). Archived from the original on January 11, 2015 ; accessed on November 15, 2016 . .
Data sheet at PROTA4u .

Individual evidence

↑ ^a ^b ^c data sheet at PROTA4u . ( Memento of the original from November 15, 2016 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice.

↑ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ ^j Rudi Wagenführ: Wooden atlas. 6th edition, Carl Hansa Verlag, 2007, ISBN 978-3-446-40649-0 .

↑ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ ^j ^k ^l ^m ⁿ ^o AT Tchinda: Entandrophragma angolense (Welw.) C.DC. In: D. Louppe, AA Oteng-Amoako, M. Brink, (Editors): Prota 7, 1: Timbers / Bois d'œuvre 1. CD-Rom. PROTA, Wageningen, Netherlands, 2008: Online at PROTA4u . Archived from the original on January 11, 2015 ; accessed on November 15, 2016 . .

^ Karl-Hermann Schmincke: Dendrology and silviculture of the most important tree species in West Africa in terms of timber. Diploma thesis, University of Hamburg, Center for Wood Industry, 1961.

↑ Entandrophragma angolense in the IUCN Red List of Threatened Species 2014.3. Listed by: Hawthorne, W., 1998. Retrieved January 15, 2015.
↑ CITES - cites.org .
↑ Data sheet with distribution map of the locations of deposited herbarium specimens in the African Plant Database of the Conservatory and Botanical Gardens of the City of Geneva "Système d'informations botanique de Genève" = SIGB.
^ ^A ^b Association of German Timber Importers V., 1976: Information Service Wood, Leaflet Series Wood Types, Hamburg
↑ ^a ^b ^c Klaus-Günther Dahms: Small wood dictionary. 6th edition, Wegra-Verlagsgesellschaft mbH Stuttgart, 1994, ISBN 978-3-921546-16-1 .

Web links

HG Richter, MJ Dallwitz: Entandrophragma angolense (Welw.) C. DC. (Tiama) - data sheet for commercial timbers from DELTA.
Datasheet at EcoPort 1.5, 2006 - Ecoport.org .
Data sheet at The virtual field herbarium .
Tiama on schreiner-seiten.de, accessed on November 15, 2016.