AMERICAN WALNUTAmerican walnut is one of the most sought-after species in markets across the world and is unique to North America. LATIN NAMEJuglans nigra OTHER COMMON NAMESblack walnut |
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FOREST DISTRIBUTION
COMPARE SPECIESAmerican walnut trees grow very widely across the eastern USA in mixed hardwood forests and on farms, concentrated in central states but spread from Texas to the eastern seaboard. The trees are one of the few hardwood species planted as well as occurring and regenerated naturally. They grow relatively tall and straight with few lower branches.
MATERIAL AVAILABILITY
COMPARE SPECIESWalnut from the USA is available as sawn lumber and as veneer. The lumber is generally sold un-steamed and unselected for colour. Specialist producers may offer steamed walnut intended to darken the sapwood and thus reduce the colour difference between heartwood and sapwood. Recent years have seen huge global demand for this species. NHLA Grading Rules are modified for walnut, allowing smaller specifications and smaller clear cuttings and sapwood is admitted without limit. Consultation with suppliers is recommended.
WOOD DESCRIPTION
COMPARE SPECIESThe sapwood of walnut is creamy white, whereas the heartwood is light brown to dark chocolate brown, making the difference in colour quite distinct. Occasionally the heartwood has dark, even purple, streaks. The wood of walnut is generally straight grained, although sometimes with wavy or curly grain that produces its characteristic and attractive figure, sought after by designers. American walnut is quite different to European walnut, which tends to be lighter in colour.
MECHANICAL PROPERTIES
Walnut is tough, hard and of medium density. It has moderate bending and crushing strengths and is low in stiffness. It has good steam bending classification.
0.55Specific Gravity(12% M.C.) |
6,093kg/m3Average Weight(12% M.C.) |
10.20%Average Volume Shrinkage(Green to 6% M.C.) |
100.68MPaModulus of Rupture |
11,584MPaModulus of Elasticity |
52.26MPaCompressive strength (parallel to grain) |
4,492NHardness |
Oiled / Un-Oiled Appearance
COMPARE SPECIESPERFORMANCE
COMPARE SPECIES
● American walnut works easily with hand and machine tools. It has excellent planing, turning and moulding properties. It has good nailing and gluing properties and can be stained and polished to an excellent finish. The wood dries slowly and has good dimensional stability when dry.
● The wood is rated as very resistant to heartwood decay and is one of the most durable (decay resistant) American hardwoods.
MAIN USES
COMPARE SPECIESWalnut is considered one of the supreme species for high end furniture, cabinets, doors and interior joinery. It is used for flooring and panelling and it is widely used to contrast with other hardwoods.