RED ALDER
(Alnus Oregona)

Many species of alder are found in various parts of the world, and on both sides of the equator, but chiefly in the northern hemisphere. Some of these are trees, others are shrubs. Six species belonging in the tree class grow in the United States, besides others which remain shrubs. Some trees are burdened with names, changing them with locality, but not so with alder. An adjective may accompany the name, as red, white, seaside, or mountain, to describe it, but it is always alder, no matter where it grows. The different species cover much of the United States, and few large areas are found which have not one or more species. It grows from sea level up to 7,000 feet or more, but some species thrive at one elevation, and others above or below.

The alders are old inhabitants of the earth. They had a place in the Eocene and Miocene forests of the old world and new. It is not apparent that they have either gained or lost in extent of range during the hundreds of thousands of years which measure their tenancy on the earth. They have not been aggressive in pushing their way, nor have they shown a disposition to retire before the aggression of other trees. Some alders bear seeds equipped with wings for wind distribution, others produce wingless seeds which depend on water to bear them to suitable situations and plant them. Of course, the water-borne seeds are planted on muddy shores or on the banks of running streams, and the trees of those species are confined to such situations. The alders belong to the birch family.

Red alder is the largest of the alder group in this country. Mature trees are from forty to ninety feet high, and from one to three feet in diameter. The northern limit of its range crosses southern Alaska; its southern border is in southern California. It is a Pacific coast tree, with a north and south range of 2,000 miles. Trunks are straight, and branches are generally slender. The largest specimens grow in the vicinity of Puget Sound. The bark is thin, leaves are from three to ten inches long, cones from one-half to one inch in length, seeds have very narrow, thin wings, and are about the size of radish seeds. The cones remain green in color until the seeds are fully ripe, but they finally turn brown, and seeds are liberated during the fall and winter.

Red alder is given that name because the newly cut wood is liable to change quickly to a reddish-brown. This applies to the whitish sapwood only; but since the trunk is largely sapwood, it is an important matter. It is not apparent whether the change in color is due to attack by fungi, or to some chemical change in the sap. It is not believed that the change in color weakens the wood, at least it does not appear to do so immediately. The heart is reddish, and when dressed and polished, it presents a fine appearance.

Red alder when thoroughly air dry weighs about thirty pounds per cubic foot, which is slightly above the weight of basswood. It is strong for its weight, rating only eight per cent below white oak, while in stiffness or elasticity it is about twelve per cent above white oak. It is not difficult to season, is soft, stands well when made up, and is one of the most important hardwoods of the northwest Pacific coast. More than 2,000,000 feet a year go to wood-using factories in Washington and Oregon.

The Indians of the Northwest, when they had only stone hatchets or the crudest kinds of metal tools, found red alder a wood which worked so easily that they specialized with it. They made canoes of the largest trunks, and all manner of troughs, trays, trenches, platters, and dugouts, some of no more than a pint in capacity, others holding three or four bushels. The Field Museum in Chicago has a collection of these Indian utensils made of alder. The workmanship shows considerable skill mixed with barbaric art. There are carvings of eagles and bears which are not entirely grotesque. The utensils were designed primarily to contain food at ceremonial feasts, or it was stored for times of scarcity. Among them are cooking vessels of alder in which meat was boiled by filling the troughs with water and dropping in hot stones.

Furniture manufacturers are the largest users of red alder. Carefully selected heartwood, finished in the proper color, looks much like cherry, though it lacks something of the characteristic cherry luster. The sapwood in its natural color resembles the sapwood of yellow birch. The annual rings are defined by narrow bands of dense summerwood. The pores are small and diffused through the entire ring, as with birch. Medullary rays are very thin and do not show much figure; neither do the rings of growth, in tangential sawing, display much contrast. It is, therefore, a figureless wood, entering into practically all grades of furniture, in the region where alder is plentiful, but it shows to particularly good advantage in panels.

Reports on wood-utilization on the Pacific coast list this wood for archery bows but particulars as to amount used, and why it is used at all, are not given. The physical properties of the wood do not seem to fit it for that use. It is wanting in both strength and elasticity which are the prime, almost the only, factors considered in selecting bow wood. No account has been found of any employment of alder for bows by Indians of the region where it grows.

Broom handle turners in Washington use 350,000 feet of alder a year. The smooth finish which may be imparted to the wood constitutes its chief value for broom handles. It is well liked for porch columns. When the center is bored out, the wood seldom checks. In that respect it resembles yellow poplar. It takes paint well and holds it a long time. Comparatively large amounts are converted into interior finish. It is made into spindles, newel posts, railing, panels, molding, ornaments, and pedestals. Occasionally it is finished in the wood’s natural color.

Many minor places are found for red alder. Frames of pack saddles are made of it; it forms parts of pulleys; is available for small turnery; and it is sometimes worked into bodies and compartments for business wagons, such as butchers and bakers use. The bark is rich in tannin and is said to be employed in local tanneries, but no statistics are available showing the annual supply.

White Alder (Alnus rhombifolia) is known simply as alder in the region where it grows. Where this tree and red alder occupy the same range they are commonly supposed to be the same. The range of white alder extends from northern Idaho to southern California. It is the common alder of central California where it attains its best development, and the only alder at low altitudes in southern California. Trees vary in height from thirty to eighty feet, and in diameter from one to three. A common size is fifty feet high and fifteen inches in diameter. Like most alders, it sticks close to water courses, and is usually found in the bottoms of gulches where water flows most of the year. The flowers begin to appear in midsummer as dark, olive-brown catkins less than an inch in length. By midwinter they are fully developed, and the tree is loaded with catkins from four to six inches long and thick as lead pencils. In the gulches among the elevated foothills it is not unusual for trees to be bending beneath snow and flowers at the same time. That is about the period when the seeds of the preceding year complete their dispersal. The cones hang closed nearly a whole twelve months, and when they give up their seeds, they often do it slowly. The seeds are the size of pin heads, and seem to have had wings once, but lost them. The remnants remain, but are of no use. If running water does not carry seeds to new grounds they lie beneath the parent tree. The wood of white alder is five pounds lighter per cubic foot than red alder. Its structure is less satisfactory. Medullary rays are irregular, some being thin as those of sweet birch, while others are as broad as rays of chestnut oak. Those of large size seem to be scattered at haphazard, and are so irregular and uncertain that no dependence can be placed in them for figure. Trees are largely sapwood, which is nearly white when freshly cut, but it quickly turns brown; heartwood is pale, yellowish-brown. This is said to be one of most quickly-decaying woods of the western forests when logs are left lying in damp woods. The white alder ought to be suitable for nearly every purpose for which red alder is used.