Heartwood

“ As a tree increases in age and diameter an inner portion of the sapwood becomes inactive and finally ceases to function. This inert or dead portion is called heartwood, deriving its name solely from its position and not from any vital importance to the tree, as is shown by the fact that a tree can thrive with its heart completely decayed. ”

“ Ontario and Florida, westward intermittently to Nebraska and Texas. Best developed in Western States.
Features of Tree.
Forty-five to sixty feet in height, one to two feet in diameter. Characteristic shape, mucilaginous inner bark. Buds hairy. Leaves, larger than American Elm, are rough when rubbed either way.
Color, Appearance, or Grain of Wood.
Heartwood dark brown or red, sapwood lighter, compact structure, annual layers marked by rows of large open ducts. Heartwood greatly preponderates. ”

“ One can tell the age of a tree by counting the number of annual rings. Sometimes, because of the interruption of normal growth, two false rings may be produced instead of a single true ring. However, such blemishes are easy for the trained eye to recognize. Heartwood does not occur in all varieties of trees. In some cases, where both heartwood and sapwood appear, it is difficult to distinguish between them as their colors are so nearly alike. Because it takes up so much moisture and plant food, sapwood rots much more quickly than heartwood. ”

“ The trunk’s value increases with age. The dark colored heartwood only is merchantable, and young trees have little heartwood. The thick, white sap constitutes most of the trunk until long after the tree has reached small sawlog size. Then the transformation to the dark, valuable heartwood goes on with fair rapidity, and the outer shell of sapwood becomes thinner as the heart increases, and in time a trunk is produced which is fit for good logs. Value comes only with age. ”

“ Trees or rarely shrubs, with deeply furrowed and sometimes laminate or with thin and scaly bark, hard or often soft heartwood often conspicuously marked by dark bands of summer cells impregnated with resin, pale nearly white sapwood, and large branch-buds formed during summer and composed of minute buds in the axils of bud-scales, becoming the bracts of the spring shoot. ”

“ More than 20 such rings may be counted in the sapwood of a log such as we have mentioned, and more than 30 in the heartwood. The pithless centre is usually out of the axis. The medullary rays are not visible to the naked eye, but may be seen by a lens to be very numerous and equidistant. The pores of the heartwood may be distinguished as containing a brownish resin, while those of the outermost layer of sapwood are empty. ”

“ There is much difference in the proportion of heartwood to sapwood in different trees. It does not seem to be a matter of size, nor wholly of age. Small trunks sometimes have more heart than large ones. A tree a hundred years old may have heartwood scarcely larger than a lead pencil, and occasionally there is none. In other instances the heart is comparatively large.
Persimmon has never been a wood of many uses, as hickory and oak have been. ”

“ The heartwood of wahoo is white, with a slight tinge of orange. The sapwood, scarcely distinguishable from the heartwood, is more nearly white in tone. The wood is heavy and close-grained but not very hard. It weighs when seasoned a little less than forty pounds to the cubic foot. Such of this wood as is sawed into lumber, which is but a small quantity, sells commercially with poplar saps, thus masquerading like its forest fellow, the cucumber tree. The character of the wood is such that it will not stand exposure to the weather any length of time. ”

“ Sometimes the folds of bark within the creases almost reach the center of the tree. The sapwood is thin, the heartwood irregular in color. Some is darker than the heartwood of southern red cedar, other is clouded and mottled, pale yellow, cream-colored, the shade of slate, or streaked with various tints. The wood can be economically worked only as small pieces. It takes a soft and pleasing finish. It is a lathe wood and shows to best advantage as balusters, ornaments, grill spindles and small posts, Indian clubs, dumb-bells, balls, and lodge gavels. ”

“ In most instances the substances deposited in the heartwood, and associated with the coloring matter, tend to preserve the wood from decay. For that reason heart timber lasts longer than sap when exposed in damp situations. The dark and variegated shades of the heartwood of some species give them their chief value as cabinet and furniture material. The sapwood of black walnut is not wanted by anybody, for it is light in color and is characterless ”

“ As the size of the trunk increases, the bark unable to expand, cracks in fissures or peels in layers, and is pushed off by the tremendous growing power from within. The heartwood is not a living part of the structure and often trees live for years without it,—hollow shells with a normal amount of vitality so long as the roots, the cambium layer and the buds are not injured. ”

“ It grows in southern California and Arizona, and there it thrives in gulches and depressions in the desert, frequently associated with mesquite. It is so heavy that perfectly dry wood will sink in water. The heartwood is deep chocolate-brown, mottled with red, the thin sapwood is lemon-yellow. Its hardness renders it difficult to work, and it can scarcely be split. The wood is made into canes and other small articles of great beauty. It is not abundant, and the small supply is remote from manufacturing centers ”

“ Sapwood is generally of a white or light color, almost invariably lighter in color than the heartwood, and is very conspicuous in the darker-colored woods, as for instance the yellow sapwood of mahogany and similiar colored woods, and the reddish brown heartwood ”

“ In certain kinds of trees, for instance, species of pines and leaf-shedding oaks, after the wood has attained a certain age, it darkens in color, so that when a crosscut of a 100-year-old part of the trunk is taken, the darker older central wood contrasts as heartwood with the surrounding pale sapwood. ”

“ Fig. 227. Wood heavy, hard, strong, of fine texture: sapwood yellowish white, heartwood reddish to brown. The wood shrinks considerably in drying, works and stands well, takes a good polish, and is much esteemed for its beauty. Cherry is used chiefly as a decorative finishing lumber for buildings, cars and boats, also for furniture and for turnery. It is becoming too costly for many purposes for which it is naturally suited. ”

“ Dogwood is about four pounds per cubic foot heavier than white oak, has the same breaking strength, and is lower in elasticity. It is quite commonly believed that this tree has no heartwood, but the belief is erroneous. ”

“ Heartwood is light brown in color, often nearly white; sapwood hardly distinguishable, fine grain, fibres interwoven. Wood is heavy, not hard, difficult to work, strong, very tough, checks and warps considerably in drying, not durable. It is distributed from Maine to southern Ontario, through central Michigan to southeastern Missouri, southward to the valley of the Brazos River in Texas, and eastward to the Kissimmee River and Tampa Bay in Florida. ”

“ If we consider only the heartwood, the black color of the persimmon, the dark brown of the walnut, the light brown of the white oaks, the reddish brown of the red oaks, the yellowish white of the tulip and poplars, the brownish red of the redwood and cedars, the yellow of the papaw and sumac, are all reliable marks of distinction and color. Together with luster and weight, they are only too often the only features depended upon in practice. Newly formed wood, like that of the outer few rings, has but little color. ”

“ The inner side of the middle layer produces new wood while the outer side grows bark. The third layer is responsible for the production of the tough, outer bark. Year after year new layers of wood are formed around the first layers. This first layer finally develops into heartwood, which, so far as growth is concerned, is dead material. Its cells are blocked up and prevent the flow of sap. It aids in supporting the tree. The living sapwood surrounds the heartwood. ”

“ Once inside, in the heartwood, the fungus may work up and down in the interior of the trunk, softening the wood by its decaying action, or "dozing" it, as the lumbermen say. If the tree, thus deprived of the firmness of its solid cylinder of heartwood, its chief mechanical support, does not fall a prey to the next violent windstorm, it is in any case weakened, and the way lies open for attack upon its last stronghold, the sapwood and living bark. ”

“ The western pine generally grows rapidly and the annual rings are wide; but, like most other species, it varies in its rate of growth, and trunks are found with narrow rings. The summerwood is thin, not conspicuous, and slightly resinous. The small resin passages are numerous. The heartwood is fairly durable in contact with the soil. ”

“ Sometimes trees grown in the open may become of considerable size, a foot or more in diameter, before any heartwood begins to form, for example, in second-growth hickory, or field-grown white and loblolly pines. ”

“ The Wood.—The heartwood is a light, clean yellow. The sapwood is a dirty white. Frequently the whole wood is a dirty white or grey, but this is due to discolourations from mould and the wood should always be seasoned in dry air and not allowed to get wet. ”

“ Winter-buds: axillary, broad-ovoid, acute, 1⁄8′ long, with thick imbricated dark red-brown or purple lustrous scales often persistent at the base of young branchlets during the season. Bark of the trunk 3⁄4′—1′ thick, dark brown tinged with red, or dark gray, and deeply divided into thick square plates broken into thin persistent scales, with heavy strong dark brown sometimes nearly black heartwood often undeveloped until the tree is over one hundred years old; used in turnery, for shoe-lasts, plane-stocks, and preferred for shuttles to other American woods. ”

“ Red Fir (Pseudotsuga taxifolia) (Oregon Pine, Puget Sound Pine, Yellow Fir, Douglas Spruce, Red Pine) . Heartwood light red or yellow in color, sapwood narrow, nearly white, comparatively free from resins, variable annual rings. Wood usually hard, strong, difficult to work, durable, splinters easily. Used for heavy construction, dimension timber, railway ties, doors, blinds, interior finish, piles, etc. ”

“ Some, species begin to form heartwood very early in life, while in others the change comes slowly. Thin sapwood is characteristic of such trees as chestnut, black locust, mulberry, Osage orange, and sassafras, while in maple, ash, gum, hickory, hackberry, beech, and loblolly pine, thick sapwood is the rule. ”

“ It ranks with lodgepole pine in that respect. Nature can afford to wait two hundred years for a forest to mature, but men will not plant and protect when the prospect of returns is so remote. The wood is light, weak, moderately stiff and hard. The heartwood is pale brown, the sap nearly white. The summerwood appears in thin but well-marked bands in the annual rings, and the medullary rays are large enough to show slightly in quarter-sawed lumber. Growing as it does, interspersed with really valuable woods, the lovely fir is not highly thought of from a commercial standpoint. ”

“ Let us pile up the fire anew with drift-wood, Annie. We can choose at random; for our logs came from no single forest. It is considered an important branch of skill in the country to know the varieties of firewood, and to choose among them well. But to-night we have the whole Atlantic shore for our wood-pile, and the Gulf Stream for a teamster. Every foreign tree of rarest name may, for aught we know, send its treasures to our hearth. Logwood and satinwood may mingle with cedar and maple; the old cellar floors of this once princely town are of mahogany, and why not our fire? ”