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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. Blunting Effect Boring Carving Common Names Common Uses Countries of Distribution Cutting Resistance Drying Defects Ease of Drying Environmental Profile Family Name Gluing Grain Heartwood Color Kiln Drying Rate Kiln Schedules Light-Induced Color Change Luster Mortising Moulding Movement in Service Nailing Natural Durability Natural Growth Defects Numerical Data Odor Painting Planing Polishing Product Sources References Regions of Distribution Resistance to Impregnation Resistance to Splitting Response to Hand Tools Routing & Recessing Sapwood Color Scientific Name Screwing Staining Strength Properties Synonyms Texture Trade Name Tree Identification Tree Size Turning Veneering Qualities Scientific Name Baikiaea insignis Trade Name Nkoba Family Name Leguminosae Synonyms Baikiaea eminii, Baikiaea minor, Baikiaea suzannae Common Names Nkoba, Nkobakoba Regions of Distribution Africa Countries of Distribution  [VIEW MAP] Tanzania, Uganda Common Uses Agricultural implements, Boat building (general), Cabinetmaking, Carvings, Concrete formwork, Flooring, Flooring: industrial heavy traffic, Furniture, Heavy construction, Joinery, Light construction, Paneling, Piling, Plywood, Railroad ties, Veneer Environmental Profile Abundant/Secure Heartwood Color Red Brown Yellow Purple Green/grey Orange Dark brown Yellow to golden-yellow to orange Pale brown Pale red to pink Greenish to greyish Sapwood Color White Yellow Brown Well defined Pinkish Different than heartwood Same as heartwood Grain Straight Even Straight Texture Fine Medium Medium Luster Medium Natural Growth Defects Gum and mineral deposits Natural Durability Durable Very durable Susceptible to insect attack Resistant to termites Resistant to powder post beetles Non durable Pinworms (ambrosia beetles) may be present in the felled log Susceptible to attack from termites (Isoptera) Susceptible to marine borer attack Susceptible to attack from powder post (Lyctid & Bostrychid) beetles Pinworms (ambrosia beetles) are commonly present Odor Has an odor Light-Induced Color Change Lighter Kiln Schedules UK=C US=T3C2/T3C1 Fr=3 Kiln Drying Rate (in days) is rather slow Kiln Drying Rate (in days) is fairly rapid UK=D US=T3D2/T3C1 Dry at a slow speed Drying Defects Distortion Checking Moderate cupping Slight surface checking Severe twisting/warping Moderate twist/warp Moderate surface checking Ease of Drying Slowly Easy Kiln Drying Rate Naturally dries slowly Slow (18-28 days for boards < 32 mm, to 52-84 days for boards >= 63 mm) Fairly rapid (11-17 days for boards under 32 mm, to 31-51 days for boards greater than 63 mm) Tree Identification Bole/stem form is misshapen Bole/stem form is fluted Tree Size Tree height is 20-30 m Tree height is 10-20 m Tree height is 30-40 m Tree height is 0-10 m Sapwood width is 10-15 cm Bole length is 20-30 m Sapwood width is 5-10 cm Trunk diameter is 100-150 cm Product Sources The ITTO reports that timber from this species is produced and exported only in low volumes. Blunting Effect High to severe Boring Fair to good results Moderately easy Carving Fair to Good Results Cutting Resistance Easy to saw Cutting Resistance with green wood is difficult Cutting Resistance with green wood is moderate Cutting Resistance with green wood is easy Cutting Resistance with dry wood is moderate Cutting Resistance with dry wood is difficult Gluing Fairly Easy to Very Easy Fair to Good Results Mortising Fair to Good Results Finishes satisfactorily Moulding Fair to Good Results Good finishing results Movement in Service Medium Nailing Fair to Good Results Very Good to Excellent Results Planing Fair to Good Results Fairly Difficult to Very Difficult Ease of planing is moderate Easy to plane Resistance to Impregnation Resistant heartwood Resistant sapwood Sapwood is moderately resistant Heartwood is extremely resistant Heartwood is resistant Resistance to Splitting Satisfactory Response to Hand Tools Easy to Work Easy to machine Routing & Recessing Fair to Good Results Screwing Very Good to Excellent Results Fair to Good Results Turning Fair to Good Results Veneering Qualities Suitable for peeling Suitable for slicing No drying degrade. Dries flat without splitting Easy to cut Painting Good results Polishing Fair to Good Results Good results Staining Fair to Good Results Fairly Difficult to Very Difficult Fairly Easy to Very Easy Reacts with Iron to discolour wood Finish is generally good Strength Properties Density (dry weight) = 46-52 lbs/cu. ft. Max. crushing strength = high Bending strength (MOR) = medium Shrinkage, Radial = small Shrinkage, Tangential = moderate Shearing strength (parallel to grain) = low Modulus of Elasticity (stiffness) = high Hardness (side grain) = medium Shrinkage, Radial = very small Shrinkage, Tangential = very small Shearing strength (parallel to grain) = medium Modulus of Elasticity (stiffness) = medium Density (dry weight) = 53-60 lbs/cu. ft Shrinkage, Tangential = small Numerical Data Item Green Dry English Bending Strength 9310 14566 psi Density 48 lbs/ft3 Hardness 1658 lbs Maximum Crushing Strength 6899 9945 psi Shearing Strength 1775 psi Stiffness 1999 2304 1000 psi Weight 47 38 lbs/ft3 Radial Shrinkage 3 % Tangential Shrinkage 6 % Item Green Dry Metric Bending Strength 654 1024 kg/cm2 Density 769 kg/m3 Hardness 752 kg Maximum Crushing Strength 485 699 kg/cm2 Shearing Strength 124 kg/cm2 Stiffness 140 161 1000 kg/cm2 Weight 753 608 kg/m3 Radial Shrinkage 3 % 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 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 Chudnoff, M.,1984,Tropical Timbers of the World,U.S.A. Department of Agriculture, Forest Service, Forest Products,Laboratory, Madison. Eggeling, W.J.,1940,Indigenous Trees of Uganda,Govt. Printer Entebbe Uganda I.U.F.R.O.,1973,Veneer Species of the World,Assembled at F.P.L. Madison on behalf of I.U.F.R.O. Working Party on,Slicing and Veneer Cutting Murira, K.,1984,Natural Durability Tests of Tanzanian Timbers 1955 - 1982,Tanzania Forestry Research Institute, Timber Utilisation Research Centre,,Moshi. Tack, C.H.,1958,The Strength Properties of some Uganda Timbers,Uganda Forest Department Bulletin No. 5 Tack, C.H.,1969,Uganda Timbers,Govt. Printer Uganda 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 Forest Department,1960,The Natural Durability of Local Timbers,Tanzanian Forest Dept. Tech. Note,No.14 Tanzania Forest Division,1966,Kiln Drying Schedules for Tanzania Timbers Technical Note no.38,Tanzania Forest Div. Util. Sec. Moshi Tanzania Forestry Department,1961,Timbers of Tanganyika - Baikiaeae insignis,Tanzania Forestry Department, Utilisation Section, Moshi - Timbers of,Tanganyika Uganda Forest Department,1969,The Shrinkage of Some Ugandan Timbers,Uganda Forestry Department Timber Leaflet,No.47