Select Language:  

EMIEN (Alstonia congensis)

Trade Name

Emien

Scientific Name

Alstonia congensis De Wild.

Family

APOCYNACEAE

Common Names

Kaiwi (Sierra Leone); Awun (Nigeria); Ahun (Nigeria); Sindru (Ghana); Emien (Côte d`Ivoire); stoolwood (United Kingdom); Patternwood (United Kingdom); Akuka (Zaire); Ekuk (Gabon); Ekouk (Gabon); Ekuk (Equatorial Guinea); Ekouk (Equatorial Guinea); Tsongati (Congo); Ekuk (Cameroon); Ekouk (Cameroon); Mujwa (Uganda); Alstonia (Uganda); Wokuka; Vhu; Uguwa; Tsongutti; Tsongoti; Sundra; Stoolwood; Sindru; Senedur; Patternwood; Onguie; Omujwe; Nyemidua; Nyamelebaka; Nsiwa; N`songuti; Musoga; Mukoge; Mujwa; Mujua; Mogvga; Mogoliga; Lomba; Kuge; Kolowuli; Kigima; Kauwi; Kanja; Kaiwi; Emien; Emenle; Emee; Ekouk; Ebwu; Ebo; Duku; Dsen-nuru; Dnyame-dua; Cheese wood; Bokuka; Bokuk; Binu; Bantang foro; Bakunin; Awun; Alstonia; Ahun; Adawura; Adawra

Scientific Name Synonyms

Alstonia gilletii De Wild.

Description Of The Tree

Botanical Description

The tree reaches a height of 43 m. The bole is usually cylindrical and clear to 26 m in length. The trunk diameter attains 70 to130 cm over a deeply fluted and buttressed base.

Natural Habitat

Alstonia congensis is reported to be abundant in the humid forests of Cameroon.

Natural Distribution

Widely distributed throughout West and Central Africa.

Wood Identification

Anatomic Description Of Wood

Wood diffuse porous. Vessels in radial multiples of 4 or more common. Tangential diameter of vessel lumina 150 to 200 micras (medium). Tyloses thin walled. Vessels per mm2 less than 6 (rare). Simple perforation plates. Vessel-ray pits similar to intervessel pit Axial parenchyma in continuous tangential lines or fine bands. Non-crystals in axial parenchyma cells. Prismatic crystals in short chains in chambered axial parenchyma cells. 5 to 8 cells per parenchyma strand. Axial parenchyma in narrow bands on lines up to 4 to 10 rays per mm (medium). Rays non-storied. Rays 1 to 4 seriate. Heterogeneous rays and/or multiseriate heterogeneous rays. Non-septate fibers. Fibers with distinctly bordered pits. Fibers with vestured pits.

  • Wood Macro Photo Tangential Plane
  • Wood Micro Photo Of Transversal Section

Availability

Cites Status

Unrestricted

General Wood Description

Color

The heartwood is white to yellowish white, it is not demarcated. The silver figure is fine (barely visible).

COLOR INDEX (1=Black, 7=Light yellow,white)

6

Grain

Straight; grain has no particular influence on drying, machining and finishing qualities.

Texture

This species is reported to have a fine to medium texture.

Luster

Luster is reported to be low.

Natural Durability

Not durable; important risks of decay attacks at any processing step, from logs up to final products. It must receive preservative treatment. Sensible to termites attack. Heartwood is sensible to Lyctus attacks.

Natural durability index (1= Very high durability, 7=Vey low durability)

5

Internal Growth Stresses

No residual growth stresses are found.

Resistance To Impregnation

Easy to treat with a full penetration of the preservative products using vacuum-pressure method.

Wood Physical Properties

Basic Density or Specific Gravity (O.D. weight/vol. green) (g/cm³)

0.33

Air-dry Density (Weight and volume at 12%MC) (g/cm³)

0.35

Total shrinkage Tangential (Saturated to 0%MC) (%)

5.5

Total shrinkage Radial (Saturated to 0%MC) (%)

4.0

Drying Defects

Ease of Drying: Drying is rather slow and sometimes difficult to perform. Drying Defects: Risks of distortions.

Recommended Dry Kiln Schedule

FR-2

Dimensional stability ratio (Total Tangential Shrinkage %/Total Radial Shrinkage %)

1.4

Wood Chemical Properties

Wood Mechanical Properties

Bending Strength (MOR),12%MC (kgf/cm²)

601

Stiffness (MOE) 12%MC (kgf/cm²)

66235

Compression parallel to fiber 12%MC (kgf/cm²)

275

Workability

Sawing

It is easy to saw.

Rotary Veneer Cutting

Suitable for peeling without treatment.

Sliced Veneer

Suitable for peeling without treatment.

Blunting Effect

Slight blunting effect; ordinary tools can be used for sawing and machining.

Machining

Machining of this species is reportedly easy.

Planing

Easy; no particular problems.

Moulding

Moderately easy; tools must be cautiously sharpened.

Boring

Moderately easy; tools must be cautiously sharpened.

Mortising

Moderately easy; tools must be cautiously sharpened.

Nailing

Easy to perform but low nails holding.

Gluing

Glues well if basic gluing technical rules are followed.

Sanding

Particular care is needed to avoid woolly aspect of the surface.

Polishing

Can be polished without surface preparation.

Steam Bending

Steam bending is difficult.

Response To Hand Tools

No particular problems.

REFERENCED USES

End Uses Summary

HOUSING GENERAL, boards, frames, panelling, fittings, FURNITURE AND CABINETS, common furniture, PLYWOOD AND VENEER, cores, PACKING, light packing, pallets, OTHER AND MUSICAL INSTRUMENTS, pencil, matches, door core, coffin, moldings

General Housing
  • 10 - Silica in Timbers
Boards
  • 13 - Dry kiln schedules for commercial woods. Temperate and tropical. Section III. Latin American (Mexico, Central, and South America) Woods–Conventional Temperatures
Frames
  • 16 - Woods of the World
Paneling
  • 18 - W3TROPICOS Missouri Botanical Garden
Fittings
  • 19 - Silica in Timbers
Furniture Cabinets
  • 21 - Tropical timbers of the world. Part III-Southeast Asian and Oceanian Species.
Furniture, Common
  • 23 - Handbook of Hardwoods
Panels, Veneers
  • 25 - Directory of Timber Trade Malaysia
Cores
  • 27 - Embassy of Brazil in Japan
Packing
  • 45 - Recopilación y Análisis de Estudios Tecnológicos de Maderas Peruanas
Light Packing
  • 46 - ECUADOR, Inventario y Aprovechamiento de los Bosques del Sur Ecuatoriano
Pallets
  • 48 - The strength properties of timbers
Pencils
  • 67 - Maderas latinoamericanas. VIII, Calophyllum brasilense, Couratari panamensis, Dendropanax arboreum y Bombacopsis sessilis
Matches
  • 71 - Proprietes physiques et mecaniques des bois tropicaux, premier supplement
Door Cores
  • 76 - Descripción General y Anatómica de 105 Maderas del Grupo Andino.
Coffin
  • 78 - Amazonian Timbers for the International Market
Molding
  • 79 - Padronização da Nomenclatura Comercial Brasileira das Madeiras Tropicais Amazônicas, Sugestão

Please Provide Information To View Producer Information

* Or, continue as guest