Walnut

Also called: european walnut, american black walnut, black walnut, juglans, satin walnut

Walnut is a rich brown hardwood cut from several related trees, prized above all for cabinetwork, gunstocks and fine carving. The best known are American black walnut and European walnut, and the trade also recognises a handful of harder or scarcer regional walnuts alongside them.

Black walnut and European walnut

Black walnut, the American species, typically has straight grain, works easily with tools, and stays dimensionally stable once it is in use; its rich grain and easy machining have made it prized for furniture, architectural millwork and decorative panelling. It is heavy, hard and strong, but will check, or crack along the grain, if it is not seasoned with care. Its heartwood is usually a deep chocolate brown, sometimes showing a purple tinge right after cutting, and a freshly cut face darkens further to a rich sepia when wetted, a colour compared to baker's chocolate. European walnut, sourced from regions such as Kashmir, the Caspian area and western Europe, was rated by the woodworker Nakashima (1981) among the finest furniture woods available. It remained the preferred wood for the finest gunstocks, and most Swiss carving was made from it.

Regional walnuts and lookalikes

Queensland walnut, from Australia, has a high silica content that makes it hard to work; tungsten-carbide-tipped tools are recommended for cutting it. It is cut into decorative veneer for marquetry, patterned inlay work, and panelling, and used as face veneer for plywood. Separately, freshly worked Australian walnut can carry a strongly unpleasant smell, similar to teak and some African woods. Two other timbers are commonly mistaken for walnut. Butternut can resemble black walnut in look, especially once stained, but it is neither as strong nor as hard; wetted butternut end grain, the surface exposed where wood is cut across its fibres, keeps a brown colour with a distinct orange cast, unlike black walnut's sepia. Separately again, one Indian hardwood looks superficially like walnut but is in fact harder, heavier, stronger and tougher to work. For fittings where appearance mattered most, English walnut, though scarce and hard to obtain, gave mirror frames a better look than Italian or Circassian walnut, its best available substitutes.

History in furniture-making

Walnut was, by one account, the wood most used in England for furniture before mahogany came into fashion, alongside other native woods such as oak, ash and elm. Its standing held for a long time: by the late 1800s walnut was chosen for drawing-room furniture about as often as mahogany. A lower grade of walnut was common in France for furniture and for framing machinery, and walnut was also widely used there for carving in the round from the fourteenth through the sixteenth centuries. Working in French walnut himself, Nakashima (1981) once built a cabinet entirely from the wood, including its vertical grilles and back panel; on another occasion he described deciding how to cut a nine-foot walnut log with an end crotch, the point where the trunk forks into branches, and a four-foot diameter, as a real challenge.

Other uses

Walnut is valued for gunstocks and rifle butts as well as cabinetwork; it has a high crushing strength but only medium resistance to shock, with a specific gravity of about 0.64. It was rarely used structurally for beams, being scarce and too flexible for the purpose: "Walnut, on account of its scarcity, is hardly ever used for the purposes of building; indeed it is of too flexible a nature for beams, though it appears to have been used for that purpose by the ancients," Tredgold wrote in 1871. Black walnut, together with teak, oak and mahogany, was among the main woods used for building shopfronts, though Ellis (1908) judged it a poor choice visually, chosen mainly because it was cheap.