TONSO (Ochna calodendron)
Trade Name
Tonso
Scientific Name
Ochna calodendron Gilg et Mildbraed
Family
OCHNACEAE
Common Names
Mbane noir (Congo); Tobolassongué (Central African Republic); Tonso (Cameroon); Mulébengoye (Cameroon); Tonso
Description Of The Tree
Botanical Description
The base of the tree is almost cylindrical. The bole is slightly twisted and may be up to 20 m in length, with diameters of 70 cm.
Natural Habitat
Ochna calodendron mainly occurs in semi-deciduous forests.
Natural Distribution
West and Central Africa, in Cameroon, Republic of the Congo and Central African Republic.
Wood Identification
Anatomic Description Of Wood
Vessels exclusively solitary (over 90%). Tangential diameter of vessel lumina 100 micras or less (very small). Vessels per mm2 more than 20 (very abundant). Vascular/vasicentric tracheides present. Axial parenchyma absent or extremely rare, non visible with magnifying glass (8x). Apotracheal axial parenchyma diffuse and/or diffuse in aggregates. Paratracheal axial parenchyma scanty and/or vasicentric. Rays as wide or wider than the pores. Rays of two distinct sizes. Larger rays more than 4 seriate. Silica bodies in the ray cells. Prismatic crystals in the ray cells. Heterogeneous rays and/or multiseriate heterogeneous rays.
Availability
Cites Status
Unrestricted
General Wood Description
Color
The sapwood is yellowish. The heartwood is pinkish brown to reddish brown, it is clearly demarcated.
Grain
Straight or slightly interlocked; grain has no particular influence on drying, machining and finishing qualities.
Texture
This wood has a somewhat fine texture.
Wood Physical Properties
Basic Density or Specific Gravity (O.D. weight/vol. green) (g/cm³)
0.83
Air-dry Density (Weight and volume at 12%MC) (g/cm³)
0.96
Drying Defects
Ease of Drying: Shrinkage during air drying is high to very high. Drying Defects: The wood stains readily and develops deep splits in the log when drying, but this problem does not occur when sawn fresh and stacked carefully.
Wood Chemical Properties
Wood Mechanical Properties
Bending Strength (MOR),12%MC (kgf/cm²)
1361
Stiffness (MOE) 12%MC (kgf/cm²)
177316
Compression parallel to fiber 12%MC (kgf/cm²)
798
Compression perpendicular to fiber 12%MC (kgf/cm²)
116
Shear strength radial 12%MC (kgf/cm²)
120
Janka hardness (side) 12%MC (kgf)
1160
Janka hardness (end grain) 12%MC (kgf)
1177
Workability
Sawing
Sawing of this species requires powerful equipment.
Rotary Veneer Cutting
Not suitable for veneering.
Sliced Veneer
Not suitable for veneering.
Blunting Effect
Moderate blunting effect; stellited blades for sawing and carbide tools for machining are advised.
Machining
It needs powerful tools for processing. Possible difficulties caused by interlocked grain are reported.
Planing
Moderately easy; tools must be cautiously sharpened.
Moulding
Rather difficult; special tools are needed.
Turning
30
Boring
Rather difficult; special tools are needed.
Mortising
Rather difficult; special tools are needed.
Nailing
Pre-boring is necessary.
Gluing
Difficult to glue because of high density.
Sanding
Easy to perform; it gives good results.
Polishing
Can be polished without surface preparation.
Response To Hand Tools
Working with hand tools is difficult.
REFERENCED USES
End Uses Summary
HOUSING GENERAL, beams, joists, flooring, parquet, frames, steps, TURNING, ornaments, PACKING, heavy packing
General Housing
- 10 - Silica in Timbers
Beams
- 11 - Prospect: The wood database
Joists
- 12 - Tropical timbers of the world. Part I-Tropical American Species
Flooring
- 14 - Handbook of Hardwoods
Parquet
- 15 - Empire Timbers
Frames
- 16 - Woods of the World
Steps
- 17 - Tree Conservation Database
Turning
- 30 - Embassy of Honduras in Japan
Ornaments
- 31 - Embassy of Colombia in Japan
Packing
- 45 - Recopilación y Análisis de Estudios Tecnológicos de Maderas Peruanas
Heavy Packing
- 47 - Arvores Brasileiras
Please Provide Information To View Producer Information