Common Name(s): Koto
Scientific Name: Pterygota macrocarpa
Distribution: West Africa
Tree Size: 65-100 ft (20-30 m) tall, 2-4 ft (.6-1.2 m) trunk diameter
Average Dried Weight: 37 lbs/ft3 (595 kg/m3)
Specific Gravity (Basic, 12% MC): .51, .59
Janka Hardness: 940 lbf (4,200 N)
Modulus of Rupture: 15,290 lbf/in2 (105.4 MPa)
Elastic Modulus: 1,752,000 lbf/in2 (12.08 GPa)
Crushing Strength: 7,590 lbf/in2 (52.4 MPa)
Shrinkage: Radial: 5.1%, Tangential: 10.6%, Volumetric: 15.0%, T/R Ratio: 2.1
Color/Appearance: Pale yellow heartwood; little color variation from sapwood to heartwood. Quartersawn surfaces can exhibit ray fleck. Steamed or dyed veneer is not uncommon.
Grain/Texture: Straight to slightly interlocked. Texture moderately coarse.
Endgrain: Diffuse-porous; solitary and radial multiples; large pores in no specific arrangement, very few; mineral/gum deposits occasionally present; parenchyma vasicentric, diffuse-in-aggregates, banded; medium to wide rays, spacing wide.
Rot Resistance: Rated as non-durable; poor insect resistance.
Workability: Good working characteristics, though tearout can result on pieces that have interlocked grain. Glues, stains, and finishes well.
Odor: Has a strongly unpleasant smell when green which disappears once dry.
Allergies/Toxicity: Although severe reactions are quite uncommon, Koto has been reported to cause skin irritation. See the articles Wood Allergies and Toxicity and Wood Dust Safety for more information.
Pricing/Availability: Generally available as veneer, prices are in the mid range for an imported hardwood.
Sustainability: This wood species is not listed in the CITES Appendices, but is on the IUCN Red List. It is listed as vulnerable due to a population reduction of over 20% in the past three generations, caused by a decline in its natural range, and exploitation.
Common Uses: Veneer, plywood, and furniture.
Comments: No data available.
Scans/Pictures: A special thanks to Steve Earis for providing the wood sample of this wood species.
I’m wondering about grain comparison between ash and koto. Want a finer grain. Definitely do not want it to be mistaken for oak. Which would be better? Thank you.