American black walnut (Juglans nigra)
Other names: Black walnut, American walnut
Throughout eastern USA, but principal commercial region is the Central States. One of the few American species planted as well as naturally regenerated.
The sapwood of walnut is creamy white, while the heartwood is light brown to dark chocolate brown, occasionally with a purplish cast and darker streaks. Walnut can be supplied steamed, to darken sapwood or left unsteamed. The wood is generally straight grained, but sometimes with wavy or curly grain that produces an attractive and decorative figure.
Walnut works easily with hand and machine tools, and nails, screws and glues well. It holds paint and stain very well and can be polished to an exceptional finish. It dries slowly, and care is needed to avoid kilning degrade. Walnut has good dimensional stability.
Walnut is a tough hard timber of medium density, with moderate bending and crushing strengths and low stiffness. It has a good steam bending classification.
Specific Gravity: 0.55 (12% M.C.)
Average Weight: 609 kg/m3 (12% M.C.)
Average Volumetric Shrinkage: 10.2% (Green to 6% M.C.)
Modulus of Elasticity: 11,584 MPa
Hardness: 4492 N
Rated as very resistant to heartwood decay, it is one of the most durable woods even under conditions favourable to decay. Sapwood liable to attack by powder post beetles.
USA: Reasonable availability with regional limitations.
Export: Reasonable availability in both lumber and veneer.
Furniture, cabinet making, architectural interiors, high class joinery, doors, flooring, and panelling. A favoured wood for using in contrast with lighter coloured timbers.