Scientific Name
Ricinodendron rautanenii
Trade Name
Corkwood
Family Name
Euphorbiaceae
Common Names
Corkwood, Erimado, Essessang, False balsa, Muganga, Mugongo, Mukusu, Munclalama, Mungoma, Mungongo, Muoma, Ndubalula, Ngoma, Omunquete, Rhodesian balsa, Umganuompobola, Umgoma, Umgongo, Wild almond
Regions of Distribution
Africa
Countries of Distribution [VIEW MAP]
Botswana, Congo, Tanzania, Zaire, Zambia, Zimbabwe
Common Uses
Agricultural implements, Boat building (general), Boxes and crates, Canoes, Carvings, Drawing boards, Mathematical instruments, Plywood corestock, Plywood, Pulp/Paper products, Sporting Goods, Toys
Heartwood Color
| Brown | ||||||||||||
| White | ||||||||||||
| Red | ||||||||||||
| Yellow to golden-yellow to orange | ||||||||||||
| White to cream |
Sapwood Color
| Red | ||||||||||||
| White | ||||||||||||
| Same as heartwood |
Grain
| Straight | ||||||||||||
| Wavy | ||||||||||||
| Even | ||||||||||||
| Closed | ||||||||||||
| Figure | ||||||||||||
| Weak (figure) |
| Straight | ||||||||||||
| Wavy | ||||||||||||
| Weak figure |
Texture
| Fine | ||||||||||||
| Coarse |
Natural Durability
| Moderately durable | ||||||||||||
| Non-resistant to powder post beetles | ||||||||||||
| Susceptible to insect attack | ||||||||||||
| Sapwood is susceptible to wood staining fungal attack | ||||||||||||
| Perishable | ||||||||||||
| Non durable | ||||||||||||
| Susceptible to marine borer attack | ||||||||||||
| Susceptible to attack from termites (Isoptera) | ||||||||||||
| Susceptible to attack from powder post (Lyctid & Bostrychid) beetles | ||||||||||||
| Heartwood is susceptible to wood staining fungal attack |
Kiln Schedules
| Drying (speed) is fast | ||||||||||||
| UK=K US=T13C4S/T11D3S | ||||||||||||
| Kiln Drying Rate (in days) rapid |
Drying Defects
| Distortion | ||||||||||||
| Splitting |
Kiln Drying Rate
| Rapid (<10 days for boards < 32 mm, to <30 days for boards >= 63 mm) |
Tree Size
| Tree height is 20-30 m | ||||||||||||
| Tree height is 10-20 m | ||||||||||||
| Tree height is 0-10 m |
Blunting Effect
| Blunting effect on machining is fairly severe |
Cutting Resistance
| Cutting Resistance with green wood is easy | ||||||||||||
| Cutting Resistance with dry wood is easy |
Gluing
| Fairly Easy to Very Easy | ||||||||||||
| Easy to glue |
Nailing
| Pre-Boring Recommended | ||||||||||||
| Easy to nail |
Planing
| Very Good to Excellent Results | ||||||||||||
| Fair to Good Results | ||||||||||||
| Planes well, to a good finish | ||||||||||||
| Easy to plane |
Resistance to Impregnation
| Resistant heartwood | ||||||||||||
| Resistant sapwood | ||||||||||||
| Heartwood is permeable | ||||||||||||
| Heartwood is resistant | ||||||||||||
| Heartwood is moderately resistant |
Response to Hand Tools
| Easy to machine |
Turning
| Fair to Good Results | ||||||||||||
| Fairly Difficult to Very Difficult | ||||||||||||
| Fairly Easy to Very Easy |
Painting
| Very Good to Excellent Results | ||||||||||||
| Fair to Good Results |
Polishing
| Very Good to Excellent Results | ||||||||||||
| Fair to Good Results |
Varnishing
| Very Good to Excellent Results | ||||||||||||
| Fair to Good Results | ||||||||||||
| Fairly Easy to Very Easy | ||||||||||||
| Satisfactory |
Strength Properties
| Density (dry weight)=less than 15 lbs/cu.ft. | ||||||||||||
| Max. crushing strength (stiffness) = very low | ||||||||||||
| Bending strength (MOR) = very low | ||||||||||||
| Hardness (side grain) = very soft | ||||||||||||
| Density (dry weight) = 15-22 lbs/cu. ft. | ||||||||||||
| Shrinkage, Tangential = very small | ||||||||||||
| Shrinkage, Radial = very small | ||||||||||||
| Shrinkage, Tangential = small | ||||||||||||
| Shrinkage, Radial = small | ||||||||||||
| Max. crushing strength = low | ||||||||||||
| Bending strength (MOR) = low |
Numerical Data
| Item | Green | Dry | English |
| Bending Strength | 2959 | 4369 | psi |
| Density | 9 | lbs/ft3 | |
| Hardness | 319 | lbs | |
| Maximum Crushing Strength | 902 | 1745 | psi |
| Stiffness | 1017 | 1199 | 1000 psi |
| Weight | 9 | 8 | lbs/ft3 |
| Radial Shrinkage | 2 | % | |
| Tangential Shrinkage | 4 | % | |
| Item | Green | Dry | Metric |
| Bending Strength | 208 | 307 | kg/cm2 |
| Density | 144 | kg/m3 | |
| Hardness | 144 | kg | |
| Maximum Crushing Strength | 63 | 122 | kg/cm2 |
| Stiffness | 71 | 84 | 1000 kg/cm2 |
| Weight | 144 | 128 | kg/m3 |
| Radial Shrinkage | 2 | % |
References
Armstrong, F.H.,1960,The Strength Properties of Timber,Forest Products Research Laboratory, London Bulletin,No.45
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
Fanshawe, D.B.,1962,Fifty Common Trees of Northern Rhodesia,Natural Resources Board and Forestry Department, Ndola
Ferreirinha, M.P.,1956,Madeiras do Ultramar Portugues,Garcia de Orta Revista da Junta Missoes Geog…,4(1,pp95-6
Forests Products Research Laboratory, U.K.,1956,A Handbook of Hardwoods,Forest Products Research Laboratory, Princes Risborough, Department of,Science and Industrial Research, Building Research Establishment
Goldsmith, B., Carter, D.T.,1981,The Indigenous Timbers of Zimbabwe,Forestry Commission, Zimbabwe Research Bulletin No.9
Jane, F.W.,1954,The Structure of World Timbers – 21 Muganga Musine Pilon and Hura,Timber Technology,62(2175, pp15-17
Lavers, G.M.,1983,The Strength Properties of Timber (3rd ed. revised Moore G.L.,Forest Products Research Laboratory, Princes Risborough, Building Research,Establishment Report (formerly Bulletin No.50)
Pardy, A.A.,1952,Notes on Indigenous Trees and Shrubs of S. Rhodesia (Ricinodendron,rautanenii,Ministry of Agriculture and Lands S. Rhodesia Bulletin,No.1686
Scott, M.H.,1950,Notes on the more Important African Timbers Imported into the Union with,Special Ref. to Port. E.A. Species,Journal of the South African Forestry Association,No.19,pp18-62,[South,African Forestry Journal]
Takahashi, A.,1978,Compilation of Data on the Mechanical Properties of Foreign Woods (Part,III) Africa,Shimane University, Japan, Research Report on Foreign Wood No. 7
Timber Information Assoc. Ltd.,1947,Notes on East African Timbers,TRADA, Timber Information, No.28
Zambia Forestry Department,1979,Timbers of Zambia Ricinodendron rautanenii and Trichilia emetica,Zambia Forestry Department, Division of Forest Products Research, Timbers,of Zambia – Technical note