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Clicking any heading in the main data area (at right) will scroll the page back to this top position. Use the following links to jump to the associated section in the main data. Common Names Common Uses Countries of Distribution Cutting Resistance Drying Defects Ease of Drying Family Name Gluing Grain Heartwood Color Kiln Drying Rate Kiln Schedules Mortising Moulding Nailing Natural Durability Numerical Data Planing Polishing References Regions of Distribution Resistance to Impregnation Response to Hand Tools Sapwood Color Scientific Name Screwing Strength Properties Texture Trade Name Tree Size Turning Veneering Qualities Scientific Name Cunonia capensis Trade Name Red aldar Family Name Cunoniaceae Common Names Red aldar, Red alder, Red cedar, Red els, Rode els, Rooi-els, Um qwashube, Umnqwashube Regions of Distribution Africa Countries of Distribution  [VIEW MAP] South Africa Common Uses Boat building (general), Carvings, Flooring, Food containers, Furniture, Heavy construction, Joinery, Light construction, Millwork, Moldings, Musical instruments, Paneling, Particleboard, Plywood, Poles, Posts, Railroad ties, Sporting Goods, Turnery, Vehicle parts, Wheel spokes Heartwood Color Yellow Brown Orange Green/grey Reddish brown Red Sapwood Color White Yellow Grain Weak (figure) Figure Straight Even Weak figure Straight Texture Fine Fine Natural Durability Resistant to powder post beetles Non-durable Susceptible to insect attack Perishable Non durable Susceptible to attack from powder post (Lyctid & Bostrychid) beetles Perishable Moderately durable Kiln Schedules UK=B US=T2C2/T2C1 Fr=2 Drying Defects Distortion Collapse Internal Honeycombing Possible Moderate end spitting Moderate twist/warp Moderate surface checking Ease of Drying Rapidly Easy Difficult Kiln Drying Rate Naturally dries quickly Tree Size Tree height is 30-40 m Tree height is 40-50 m Cutting Resistance Cutting Resistance with dry wood is easy Gluing Easy to glue Mortising Easy to mortise Moulding Easy to mould Nailing Very Good to Excellent Results Fair to Good Results Easy to nail Planing Easy to plane Resistance to Impregnation Resistant sapwood Resistant heartwood Permeable sapwood Permeable heartwood Response to Hand Tools Easy to Work Difficult to machine Easy to machine Screwing Very Good to Excellent Results Fair to Good Results Turning Fairly Easy to Very Easy Veneering Qualities Veneers easily Veneers moderately easy Suitable for peeling Polishing Satisfactory results Strength Properties Max. crushing strength = medium Bending strength (MOR) = medium Shearing strength (parallel to grain) = low Modulus of Elasticity (stiffness) = medium Hardness (side grain) = soft Density (dry weight) = 46-52 lbs/cu. ft. Shrinkage, Tangential = large Shrinkage, Radial = large Shrinkage, Tangential = moderate Shrinkage, Tangential = fairly large Shrinkage, Radial = fairly large Shearing strength (parallel to grain) = medium Numerical Data Item Green Dry English Bending Strength 9310 14566 psi Density 45 lbs/ft3 Hardness 995 lbs Maximum Crushing Strength 3916 6397 psi Shearing Strength 1721 psi Stiffness 1665 1923 1000 psi Weight 44 35 lbs/ft3 Radial Shrinkage 5 % Tangential Shrinkage 9 % Item Green Dry Metric Bending Strength 654 1024 kg/cm2 Density 721 kg/m3 Hardness 451 kg Maximum Crushing Strength 275 449 kg/cm2 Shearing Strength 121 kg/cm2 Stiffness 117 135 1000 kg/cm2 Weight 705 560 kg/m3 Radial Shrinkage 5 % References Banks, C.H., Schoeman, J.P., Otto, K.P.,1977,The Mechanical Properties of Timbers with particular reference to South,Africa,South African Forestry Research Institute Bulletin,(Ed.,Schoeman, J.P. 1973 & Otto K.P. 1976,No.48 Banks, C.H.,1954,The Mechanical Properties of Timbers with Particular Reference to those,grown in the Union of South Africa,Journal of the South African Forestry Association,No. 24 pp.44-65,[South,African Forestry Journal] Banks, C.H.,1970,The Durability of South African Wood and Wood Base Building Materials,South African Forestry Journal,No.75 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 Chalk, L. et al.,1935,Fifteen South African High Forest Timber Trees,Forest Trees and Timbers of the British Empire, Imperial Forestry,Institute, Oxford,Part 3 Scott, M.H.,1935,Weights of South African Growth Timbers,South African Department of Agriculture and Forestry Bulletin,No.145,Forest Products Institute, Forestry Series No.1 Scott, M.H.,1948,Timber Seasoning in South Africa,South African Forestry Department South Africa Bulletin No.32 Scott, M.H.,1953,Utilisation Notes on South African Timbers,South African Forestry Department Bulletin No.36 Sim, T.R.,1921,Native Trees of South Africa,Union of South Africa Department of Mines and Industries Memoir No.3 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