Scientific Name
Uapaca heudelotii
Trade Name
Akun
Family Name
Euphorbiaceae
Common Names
Akun, Assam, Borikio, Bosenge, Kindi, Kuntan, Mole, Nsanvi, Oli, Rikio, Rikio Riviere, Sugar Plum, Yeye
Regions of Distribution
Africa
Countries of Distribution [VIEW MAP]
Benin, Cameroon, Congo, Equatorial Guinea, Gabon, Ghana, Guinea, Ivory Coast, Liberia, Mali, Nigeria, Sierra Leone, Togo, Zaire
Common Uses
Barge fenders, Bedroom suites, Building construction, Building materials, Cabin construction, Cabinetmaking, Charcoal, Construction, Crossties, Decorative plywood, Docks, Dockwork, Drawer sides, Excelsior, Factory construction, Furniture , Harbor work, Heavy construction, Interior construction, Interior trim, Joinery, Kitchen cabinets, Living-room suites, Marine construction, Millwork, Mine timbers, Moldings, Naval architecture, Office furniture, Plywood, Radio – stereo – TV cabinets, Raft floats, Rafts, Railroad ties, Trimming, Wainscotting, Wharf construction
Environmental Profile
| Status unknown in some areas due to inadequate information | ||||||||||||
| Secure within many parts of its natural range, but not completely assessed | ||||||||||||
| Data source is World Conservation Monitoring Center |
Secure in Cameroon, Congo and the Ivory Coast. Status unknown in other areas of Africa
Distribution Overview
Distributed throughout West Africa, and extends into Zaire. Its habitat is described as swampy and close to water, and it is usually found on the edge of forests in the savannah regions within its range.
Heartwood Color
| Brown | ||||||||||||
| Reddish brown |
The timber is very similar in appearance to mahogany
Sapwood Color
| Color not distinct from heartwood |
Grain
| Even | ||||||||||||
| Straight |
| Straight |
Texture
| Coarse | ||||||||||||
| Coarse |
Luster
| Low |
Natural Durability
| Perishable | ||||||||||||
| Non-resistant to powder post beetles | ||||||||||||
| Non-durable | ||||||||||||
| Moderately resistant to attack by termites | ||||||||||||
| Moderately resistant to attack by teredo worms |
Odor
| No specific smell or taste |
Silica Content
| Contains high levels of silica (> 0.5% of dry weight) |
Drying Defects
| Checking | ||||||||||||
| Distortion | ||||||||||||
| Collapse | ||||||||||||
| Splitting | ||||||||||||
| High differential shrinkage may cause distortion |
Ease of Drying
| Rapidly | ||||||||||||
| Requires special attention | ||||||||||||
| Thick Stock Requires Care | ||||||||||||
| Medium to High Shrinkage | ||||||||||||
| Use care to avoid degrade | ||||||||||||
| Difficult to season |
Tree Size
| Bole length is 10-20 m | ||||||||||||
| Tree height is 30-40 m | ||||||||||||
| Tree height is 40-50 m | ||||||||||||
| Trunk diameter is 100-150 cm |
The tree is described as large, with very well developed stilt-roots since it is always found near water. Reddish aerial roots are occasionally present, and stilt roots may be up to 19 feet (5 m) high
Certified Source
| Certified Source |
Blunting Effect
| Moderate | ||||||||||||
| Cutting edges dull severely and rapidly |
Boring
| Fairly difficult to very difficult |
Carving
| Fairly Difficult to Very Difficult |
Cutting Resistance
| Easy to saw | ||||||||||||
| Difficult to saw |
The timber is rather difficult to saw because of its density and high silica content. Saw blades may heat up
Gluing
| Fair to Good Results | ||||||||||||
| Fairly Easy to Very Easy | ||||||||||||
| Satisfactory gluing properties |
Mortising
| Fairly Difficult to Very Difficult |
Moulding
| Fairly Difficult to Very Difficult |
Movement in Service
| Fair to Good Stability – Medium Movement |
Nailing
| Very Good to Excellent Results | ||||||||||||
| Pre-boring required | ||||||||||||
| Holds nails well | ||||||||||||
| Difficult to nail |
Planing
| Fairly Difficult to Very Difficult | ||||||||||||
| High density and silica levels make the wood difficult to work in most machining operations | ||||||||||||
| Difficult to plane |
High density and high levels of silica are reported to make the material generally difficult to work in most machining operations. Planing sometimes yields fuzzy surfaces.
Resistance to Impregnation
| Permeable sapwood | ||||||||||||
| Resistant heartwood | ||||||||||||
| Resistant sapwood | ||||||||||||
| Heartwood is somewhat permeable |
Response to Hand Tools
| Fairly Difficult to Difficult to Work | ||||||||||||
| Responds poorly to hand tools |
Routing & Recessing
| Fairly Difficult to Very Difficult |
Sanding
| Satisfactory sanding properties |
Screwing
| Very Good to Excellent Results | ||||||||||||
| Fair to Good Results | ||||||||||||
| Fairly Easy to Very Easy |
Turning
| Fairly Difficult to Very Difficult | ||||||||||||
| Poor turning characteristics |
Veneering Qualities
| Suitable for slicing |
Steam Bending
| Fair to Good Results |
Polishing
| Very Good to Excellent Results | ||||||||||||
| Fairly Easy to Very Easy |
Staining
| Fair to Good Results | ||||||||||||
| Fairly Easy to Very Easy | ||||||||||||
| Very Good to Excellent Results |
Strength Properties
| Very heavy | ||||||||||||
| Dense | ||||||||||||
| Compression strength (parallel to grain) = high | ||||||||||||
| Bending strength (MOR) = high |
Some familiar species with high crushing strength parallel to grain include Hard maple, Teak, and White oak
Numerical Data
| Item | Green | Dry | English |
| Bending Strength | 8820 | 13328 | psi |
| Density | 45 | lbs/ft3 | |
| Maximum Crushing Strength | 4410 | 7595 | psi |
| Shearing Strength | 1862 | psi | |
| Stiffness | 1519 | 1764 | 1000 psi |
| Specific Gravity | 0.59 | ||
| Weight | 44 | 36. | lbs/ft3 |
| Radial Shrinkage | 5 | % | |
| Tangential Shrinkage | 10 | % | |
| Volumetric Shrinkage | 14 | % | |
| Item | Green | Dry | Metric |
| Bending Strength | 620 | 937 | kg/cm2 |
| Density | 721 | kg/m3 | |
| Maximum Crushing Strength | 310 | 533 | kg/cm2 |
| Shearing Strength | 130 | kg/cm2 | |
| Stiffness | 106 | 124 | 1000 kg/cm2 |
| Specific Gravity | 0.59 | ||
| Weight | 705 | 576. | kg/m3 |
| Radial Shrinkage | 5 | % | |
| Tangential Shrinkage | 10 | % |
References
Bolza, E., Keating, W.G.,1972,African Timbers – the Properties, Uses and Characteristics of 700 Species,C.S.I.R.O. Div. of Building Research
Keay, R.W.J. 1989. Trees of Nigeria. Revised Version of Nigerian Trees. Clarendon Press, Oxford.
WCMC. 1992. Conservation Status Listing – Trees and Timbers of the World, World Conservation Monitoring Centre, Plants Programme, 219 Huntingdon Road, Cambridge, CB3 ODL, United Kingdom.