Red alder (Alnus rubra), also called Oregon alder, western alder, and Pacific coast alder, is the most common hardwood in the Pacific Northwest. It is a relatively short-lived, intolerant pioneer with rapid juvenile growth. The species is favored by disturbance and often increases after logging and burning. Because the commercial value of alder has traditionally been lower than that of its associated conifers, most forest managers have tried to eliminate the species from conifer stands. On the other hand, red alder is the only commercial tree species west of the Rocky Mountains with the capability to fix atmospheric nitrogen, and the species is now being considered for deliberate use in some management systems.
THE TREE: On good sites, red alder can attain heights of 100 to 130 ft (30 to 40 m) and diameters of 22 to 30 inches (56 to 76 cm). The light gray bark is thin and smooth. The leaves are ovate, 7-15 cm long, with bluntly serrated edges and a distinct point at the end; the leaf margin is revolute, the very edge being curled under, a diagnostic character which distinguishes it from all other alders.
WOOD CHARACTERISTICS: Red alder wood is almost white when freshly cut but quickly changes to a light tan or light brown with a yellow or reddish tinge when exposed to the air. Heartwood is formed only in trees of advanced age, and there is no visible boundary between heartwood and sapwood.
Red alder is considered the most important commercial hardwood of the Pacific Northwest. The fine even texture and moderate density of red alder wood make it easy to work with. It sands and polishes easily, holds paints and coatings well, stains readily, and seldom splits. Due to these favorable characteristics, and the fact that it is much less expensive than other hardwoods used in furniture manufacturing, red alder wood is extensively for furniture making and cabinetry. It is also used in the manufacture of novelties, trim, paneling, pallets, veneers, plywoods, and paper roll plugs. Smaller manufactured items include brush handles, spools, trays, shoe soles, and boxes. Red alder is an important source of pulp for paper products. Research is being conducted to determine the feasibility of producing 4x8 foot (1.2-2.4 m) sheets of waferboard from chips.
GENERAL DISTRIBUTION: Red alder is confined to the Pacific Coast region from southeast Alaska to southern California. Although there is an isolated population growing along streams in northern Idaho, it ordinarily occurs no further inland than 100 miles (160 km) at elevations below 2,500 feet (762 m). Red alder is cultivated in Hawaii.