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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. Boring Common Names Common Uses Countries of Distribution Cutting Resistance Drying Defects Ease of Drying Family Name Grain Heartwood Color Kiln Drying Rate Kiln Schedules Light-Induced Color Change Luster Moulding Movement in Service Natural Durability Natural Growth Defects Numerical Data Planing Polishing References Regions of Distribution Resistance to Impregnation Resistance to Splitting Response to Hand Tools Sapwood Color Scientific Name Strength Properties Texture Trade Name Tree Identification Tree Size Scientific Name Sterculia quinqueloba Trade Name Grootblaarsterkastaiing Family Name Sterculiaceae Common Names Grootblaarsterkastaiing, Large leaved star chestnut, Large leaved sterculia, Mbalamwezi, Mguwa, Mkungulanga, Mperamusi, Muhembeti, Mwingirangidengi Regions of Distribution Africa Countries of Distribution  [VIEW MAP] South Africa, Tanzania, Zambia, Zimbabwe Common Uses Cabinetmaking, Flooring, Joinery, Light construction, Mine timbers, Piling, Plywood corestock, Plywood, Pulp/Paper products, Turnery, Veneer Heartwood Color White Yellow Orange Green/grey Brown Red Pale red to pink Reddish brown Brown Sapwood Color Red Yellow White White to yellow Well defined Grain Straight Figure Even Rays (figure) Straight Rays figure Texture Medium Medium to coarse Luster Low Natural Growth Defects Gum/resin exudation Natural Durability Durable Resistant to termites Moderately durable Moderately resistant to termite (Isoptera) attack Moderately durable Susceptible to attack from powder post (Lyctid & Bostrychid) beetles Light-Induced Color Change Darker Kiln Schedules Kiln Drying Rate (in days) is slow Dry at a slow speed UK=A US=T2D4/T2D3 Fr=1 Drying Defects Moderate cupping Moderate collapse and honeycombing Slight twist/warp Slight surface checking Slight end splitting Ease of Drying Moderately Difficult to Difficult Kiln Drying Rate Very slow (>28 days for boards < 32 mm, to >84 days for boards >= 63 mm) Tree Identification Bole/stem form is straight Bole/stem form is cylindrical Tree Size Tree height is 30-40 m Tree height is 20-30 m Tree height is 10-20 m Bole length is 0-10 m Trunk diameter is 150-200 cm Boring Moderately easy Cutting Resistance Fairly Difficult to Very Difficult to saw Moderate to saw Cutting Resistance with green wood is easy Cutting Resistance with dry wood is easy Moulding Good finishing results Movement in Service Medium Planing Planes well, to a good finish Resistance to Impregnation Sapwood is permeable Heartwood is highly resistant Resistance to Splitting Poor Response to Hand Tools Fairly Difficult to Difficult to Work Polishing Fair to Good Results Strength Properties Density (dry weight) = 46-52 lbs/cu. ft. Shrinkage, Radial = very small Bending strength (MOR) = low Max. crushing strength = medium Shrinkage, Tangential = very small Shearing strength (parallel to grain) = low Modulus of Elasticity (stiffness) = very low Shrinkage, Tangential = moderate Density (dry weight) = 53-60 lbs/cu. ft. Density (dry weight) = 38-45 lbs/cu. ft. Shrinkage, Tangential = small Shrinkage, Radial = small Shearing strength (parallel to grain) = very low Modulus of Elasticity (stiffness) = low Hardness (side grain) = soft Numerical Data Item Green Dry English Bending Strength 6111 9589 psi Density 47 lbs/ft3 Hardness 995 lbs Maximum Crushing Strength 3916 6397 psi Shearing Strength 1391 psi Stiffness 1103 1291 1000 psi Weight 46 37 lbs/ft3 Radial Shrinkage 2 % Tangential Shrinkage 5 % Item Green Dry Metric Bending Strength 429 674 kg/cm2 Density 753 kg/m3 Hardness 451 kg Maximum Crushing Strength 275 449 kg/cm2 Shearing Strength 97 kg/cm2 Stiffness 77 90 1000 kg/cm2 Weight 737 592 kg/m3 Radial Shrinkage 2 % 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 Palgrave, K.C.,1977,Trees of Southern Africa,Cape Town South Africa 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 Tanzania - Timber Marketing Co. Ltd.,1978,Timber from Tanzania Tanzania Forest Division,1966,Kiln Drying Schedules for Tanzania Timbers Technical Note no.38,Tanzania Forest Div. Util. Sec. Moshi Tanzania Forestry Department,1963,Timbers of Tanganyika - Sterculia quinqueloba,Tanzania Forestry Department, Utilisation Section, Moshi - Timbers of,Tanganyika