Part 44
River birch is widely used but in small amounts. It may properly be described as a neighborhood wood--that is, wherever it grows in considerable quantity it is put to use, but nearly always in a local way. For example, in Louisiana, where it is as abundant as in any other state, it is a favorite material for ox yokes, and no report from that state has been made of its employment for any other purpose. The reason given for its extensive use for ox yokes there is that it is very strong for its weight, and that it resists decay. The yokes there are usually left out of doors when not in use, and the dampness and hot weather cause rapid decay of most woods. The birches are usually listed as quick-decaying woods, but the verdict from Louisiana seems to be that river birch is an exception.
Plain furniture is made of it, and the manufacturers of woodenware find it suitable for most of their commodities. It is sometimes listed as wooden shoe material, but no particular instance has been reported where it has been so used in this country. In Maryland some of the manufacturers of peach baskets make bands or hoops of it, and pronounce it as satisfactory for that purpose as elm.
The supply is not in much danger of exhaustion. The species is equipped to take care of itself, occupying as it does, ground not in demand for farming purposes. When a tree once gets a start it has a chance to escape the ax until large enough for use.
WHITE ALASKA BIRCH (_Betula alaskana_) is usually called simply white birch where it grows. It is not exclusively an Alaska species though that is the only place where it touches the territory of the United States. It is supposed by some to be closely related to the white birches of northern Asia, but the relationship, if it exists, has not been established. In Alaska it grows as far north as any timber extends. It was first discovered and reported in 1858 on the Saskatchewan river, east of the Rocky Mountains, and its range is now known to extend down the valley of the Mackenzie river toward the Arctic ocean to a point more than 100 miles north of the Arctic circle. It is common in many parts of Alaska both along the coast and in the interior. In some portions of that territory it is an important source of fuel. Trees are from twenty-five to sixty feet high, and from six to eighteen inches in diameter. The bark is thin and often nearly white, separating into thin scales. The tree bears typical birch cones, but larger than those of some of the other species. No tests of the wood’s physical properties have been made, but it looks like the wood of paper birch, and will probably attain to considerable importance in the future, since it grows over a large area, and in many parts is abundant. There remain many things for both botanists and wood-users to investigate concerning this tree which has a range of more than half a million square miles.
WESTERN BIRCH (_Betula occidentalis_) is believed to be the largest birch in the world, and yet it is not of much commercial importance in the United States, because of scarcity, occurring only in northwestern Washington and in the adjacent parts of British Columbia, as far as its range has been determined. It resembles paper birch, and has often been supposed to be that tree. The people in the restricted region where it grows speak of it simply as birch. The largest trees are 100 feet high and four feet in diameter, clear of limbs forty or fifty feet. A height of seventy feet and a diameter of two are common. The general color of the trunk is orange-brown, the new bark, exposed by exfoliation, is yellow. The tree prefers the border of streams and the shores of lakes. Though it is the largest of the birches, its seeds are among the smallest. They are provided with two wings and are good flyers. Manufacturers of flooring and interior finish in Washington reported the use of 315,000 feet of this birch in 1911. That was the only use found for it in the only state where it grows. Information is meager as to the probable quantity of this birch available. It has been reported in Idaho, but exact information on the subject is lacking.
MOUNTAIN BIRCH (_Betula fontanalis_) is a minor species concerning which there has been much contention among botanists. It has finally been called mountain birch because it grows on mountains, as high as 10,000 feet among the Sierra Nevadas in California. It has many local names for a tree so small as to be almost a shrub throughout most of its range: Black birch, sweet birch, cherry birch, water birch, and canyon birch. Its bark is of the color of old copper; wood is light yellowish-brown, with thick white sapwood; trunks seldom exceed ten inches in diameter and thirty feet high; range extends from northern British Columbia to California, and along the Rocky Mountains to Colorado and possibly further south. The uses of the wood are few.
PAPER BIRCH
PAPER BIRCH
(_Betula Papyrifera_)
This tree is called paper birch because the bark parts in thin sheets like paper. It is known as canoe birch from the fact that Indians and early white explorers and travelers constructed canoes of the bark. The name silver birch is an allusion to the color of the bark; and big white birch is the name used when the purpose is to distinguish it from the white birch with which it is associated in the northeastern part of its range. It grows as far north as Arctic British America, east to Labrador, south to Michigan and Pennsylvania, and west nearly or quite to the base of the Rocky Mountains. This indicated area exceeds 1,000,000 square miles. The quantity of birch of this species in the forests is unknown, but it runs into billions of feet, probably exceeding any other single species of birch. The tree sometimes grows dispersed through forests of other woods, sometimes in nearly pure stands. Persons well acquainted with the species have expressed the opinion that paper birch exists in larger quantities now than at the time when the country was first explored by white men. That can be said of few other species; but probably holds true of lodgepole pine in the West, loblolly pine in the Southeast, and mesquite in the Southwest. Each of these species took advantage of man’s presence and influence to extend its range. Cattle spread the mesquite; the lodgepole pine came up in fire-burned tracts; loblolly pine spread into abandoned fields; and paper birch profited by fires which destroyed large tracts of timber.
The seeds are light, are furnished with wings which sail them long distances through the air, and they are quickly scattered over the burned areas where they spring up. In the contest, they are competitors of aspen. Birch often captures the ground, but does not always do it. Some of the largest stands in the Northeast occupy tracts bared by fire half a century or more ago. When paper birch does not find open tracts, it contents itself with sharing ground with other species. That was the usual manner of its growth in the original forests; but it has been quick to seize opportunities to take full possession.
It does not like shade and, if crowded, one of the first things it does is to rid its lower trunk of all branches. Only limbs remain which are at the top where they receive plenty of light. Therefore, forest-grown paper birches have long, clean trunks, though they are not always straight. The largest trees are seventy feet high and three in diameter, but those fifty feet in height and eighteen inches in diameter are above rather than under the average.
The bark of paper birch has played an important part in American history, story, and poetry. It was the canoe material, the roof, and the utensil in its region. The Indians had brought the art of canoe making to perfection before white men went among them. The bark peels from the trunks in large pieces, and may be separated into thin sheets, which are very tough, strong, and durable. The Indians sewed pieces of bark together, using the long, slender roots of tamarack for thread. The bark was stretched and tied over a frame, the shape of the canoe, and made of northern white cedar, or some other light wood. Holes in the bark, and the partings at the seams, were stopped with resin from balsam fir, wax from balm of Gilead, or resin from pine. The forest supplied all the material needed by the Indian, and a canoe thus made, and large enough to carry 800 or 1,000 pounds, weighed no more than fifty pounds. Frail as it seemed, it was good for long service on rivers and lakes, and could weather storms of no small severity.
White men adopted the bark canoes at once, and learned from Indians how to make them. The daring explorers and venturesome fur traders who threaded every river and navigated every important lake of British America, found the birch canoe equal to every requirement, even to attacking whales in the tidewater of the Arctic ocean. The bark from this birch was used for tents and the roofs of cabins; vessels in which to store or carry food were made of it, as well as beds on which to sleep, and wrapping material for bundles. These uses have now practically ceased; but as sport, recreation, and for the novelty, articles, from canoes to visiting cards, are still made of the bark.
The wood of paper birch is valuable for certain purposes. The trees are largely white sapwood, which is without figure. It is as plain a wood as grows in the forest, but it may be stained. That, however, is seldom done. The heartwood is dark or red, and is made into brush backs and parquet flooring, but the hearts are small, and no large quantity of that wood is used. The largest use of paper birch is for spools, the common kind for thread. Some of larger size are made for use in mills. The sapwood only is accepted by makers of spools. The heart is cut out, and most of it is thrown away or burned under the boilers. The qualities of paper birch which appeal to spool makers are, white color, small liability to warp, and the ease with which it may be cut without dulling the tools. The logs are worked into bars of the various spool sizes, and are carefully seasoned. One of the problems that must be constantly solved is the prevention of sap stain while the bars are seasoning. The wood discolors quickly and deeply.
Tooth picks, shoe pegs, and shoe shanks are other important commodities manufactured from paper birch. It has not yet been satisfactorily converted into lumber, because it is more valuable for spools, tooth picks, pegs, and the like. This wood is frequently listed as a pulpwood, and it is quite generally believed that its use for that purpose is important. This is apparently an error, as the wood is not even mentioned in statistics of pulpwood output in this country.
Paper birch weighs 37.11 pounds per cubic foot, is strong, hard, tough; medullary rays are numerous but very small and obscure; wood is diffuse-porous, and earlywood blends gradually with latewood in the annual rings which are not very distinct.
This is one of the woods which does not threaten to become soon exhausted. A supply for half a century, at present rate of use, is in sight, if no more should grow; but in fifty years new forests, now young, will be large enough to use.
KENAI BIRCH (_Betula kenaica_) is an Alaska species concerning which comparatively little is known, except that its botanical identity and something of its range have been established. Its small size, and the remote regions where it grows, do not necessarily indicate that it can never be important. Scarcity of other woods may give it a place which it does not now occupy. No reports on the properties of the wood have been made. The bark is deep brown in color. Trees are from twenty to thirty feet high and from twelve to eighteen inches in diameter. The trunks are very short. Cones are an inch or less in length and the double winged seeds are very small. The name applied to this species relates to the region where the best developed trees have been found. As far as known, the species is confined to the coast region of Alaska and to adjacent islands from the head of Lynn canal westward. It has been reported on Koyukuk river above the Arctic circle.
WHITE BIRCH (_Betula populifolia_) is known also as gray birch, old-field birch, poverty birch, poplar-leaved birch, and small white birch. It is chiefly confined to the northeastern part of the United States, but grows as far east as Nova Scotia, and west to the southern shore of Lake Ontario. It occurs on the Atlantic coast south to Delaware, and along mountain ranges to West Virginia. The names describe either the habits or the appearance of the tree. The bark is white, and is the most prominent feature of a thicket of these graceful but practically worthless little birches. It is called an old-field species because it quickly scatters its small, winged seeds over abandoned farmland and takes possession when it does not have to compete with stronger species. Poverty birch is an allusion, either to the poor ground it occupies or the unpromising nature of the tree itself. The resemblance of its leaves to those of cottonwood leads some people to prefer the name poplar-leaved birch. The tree at its best is seldom more than forty feet high and eighteen inches in diameter. A height of twenty or thirty feet is the usual size. The stem is generally clothed with branches nearly to the ground. The wood is light, soft, not strong or durable, heart light brown, thick sap nearly white. The form and size of the trunk exclude it from sawmills, but it has some special uses: Spools, shoe pegs, and hoops. Its small size does not disqualify it for service along those lines. The tree springs up quickly, grows with fair rapidity, and dies young. It is cut for cordwood in New England and makes good fuel. It takes possession of areas bared by fire, and protects the ground, furnishing shelter for more valuable species which come later.
BLUE BIRCH (_Betula cærulea_) is a small tree of which more information is to be desired. It is rarely more than thirty feet high with a diameter of eight or ten inches. Its leaves are long-pointed, its cones about an inch in length, the bark is thin, white tinged with rose, and is lustrous. Bark is not easily separated into layers, in that respect differing from the paper birch. The inner bark is of light orange color. It is probably put to no use, unless for fuel or as hoops. It is smallest of New England birches, and its range has not been fully determined, but it is known to grow in Maine and Vermont, and probably will be found in other parts of New England and in the adjacent regions of Canada. It has been compared with a European species of birch, the _Betula pendula_.
RED ALDER
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.