Scientific Name
Uapaca sp.
Trade Name
Sugar-plum
Family Name
Euphorbiaceae
Common Names
Abo Emido, Borikio, Rikio, Rikio Riviere, Sugar-plum, Yeye
Regions of Distribution
Africa
Countries of Distribution [VIEW MAP]
Cameroon, Ivory Coast, Nigeria
Common Uses
Balusters, Boat building, Building construction, Building materials, Canoes, Charcoal, Construction, Domestic flooring, Flooring, Fuelwood, Interior construction, Lifeboats, Light construction, Moldings, Parquet flooring, Shipbuilding, Stairworks, Stringers, Sub-flooring
Environmental Profile
| Status has not been officially assessed |
Distribution Overview
Growth range of species in the genus Uapaca is confined to tropical Africa and Madagascar. Some species develop aerial and stilt-roots since they are usually found in swampy areas and near water. Other species grow on the edges of savannah forests.
Heartwood Color
| Brown | ||||||||||||
| Green/grey | ||||||||||||
| Reddish brown | ||||||||||||
| Pale brown |
Chocloate
Sapwood Color
| Pale straw | ||||||||||||
| Color not distinct from heartwood |
Grain
| Even | ||||||||||||
| Straight |
| Straight |
Texture
| Medium to coarse |
Luster
| Low |
Natural Durability
| Heartwood resistant to decay |
Resistant to attack by termites
Odor
| No specific smell or taste |
Silica Content
| Contains high levels of silica (> 0.5% of dry weight) |
Drying Defects
| Splitting | ||||||||||||
| Shakes | ||||||||||||
| Conditions need to be controlled to yield good results | ||||||||||||
| Checking |
Ease of Drying
| Fairly Easy | ||||||||||||
| Rapidly | ||||||||||||
| Easy | ||||||||||||
| Dries well under good controlled conditions |
Quartersawn material is easier to dry
Tree Size
| Tree height is 20-30 m |
Comments
Bears edible fruit
Blunting Effect
| Rapid dulling of tools | ||||||||||||
| Blunting effect on machining is fairly severe |
Cutting Resistance
Generally difficult to saw because of density and high silica content. Saw blades tend to heat up
Gluing
| Satisfactory gluing properties |
Nailing
| Pre-boring required | ||||||||||||
| Holds nails well | ||||||||||||
| Difficult to nail |
Planing
Very difficult to work in most operations. Planing sometimes yields fuzzy surfaces
Resistance to Impregnation
| Sapwood is permeable | ||||||||||||
| Heartwood is resistant |
Response to Hand Tools
| Poor response to hand tools |
Sanding
| Fairly good sanding characteristics |
Strength Properties
High bending strength, compression strenght parallel to grain in air dry is high, high density
Numerical Data
| Item | Green | Dry | English |
| Bending Strength | 16619 | psi | |
| Density | 45 | lbs/ft3 | |
| Maximum Crushing Strength | 7417 | psi | |
| Stiffness | 2089 | 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 | 1168 | kg/cm2 | |
| Density | 721 | kg/m3 | |
| Maximum Crushing Strength | 521 | kg/cm2 | |
| Stiffness | 146 | 1000 kg/cm2 | |
| Specific Gravity | 0.59 | ||
| Weight | 705 | 576. | kg/m3 |
| Radial Shrinkage | 5 | % | |
| Tangential Shrinkage | 10 | % |
References
Chudnoff, M.,1984,Tropical Timbers of the World,U.S.A. Department of Agriculture, Forest Service, Forest Products,Laboratory, Madison.
Keay, R.W.J. 1989. Trees of Nigeria. Revised Version of Nigerian Trees. Clarendon Press, Oxford.