The Project Gutenberg eBook, The Principal Species of Wood: Their Characteristic Properties, by Charles H. (Charles Henry) Snow

Live Oak (Quercus virginiana), Louisiana.

PREFACE.

The following is a brief untechnical presentation of general features characterizing economically important species of wood. It is the result of notes originally brought together from many already existing sources and later augmented, and verified so far as possible for the present use, by personal observation. The work of preparation has not been as simple as the result would indicate, and although great care has been taken to check each fact, errors do no doubt exist, although it is not believed that there are important ones.

Engineers while writing upon woods have, save exceptionally, emphasized strength beyond most other properties. Other works for expert foresters or botanists are of necessity too special, voluminous, fragmental, or technical for the casual student. Some popular books on trees, as distinct from woods, are available. The present form is distinct from these and is intended for those who are not foresters or botanists, but who use woods or desire knowledge of their distinguishing properties. Allusions to trees, historical and other references, aside from those directly regarding woods, are made for completeness and in order to mark, distinguish, or separate the species.

Acknowledgments are particularly due to the publications of the U. S. Division of Forestry, to Prof. Sargent's studies as set forth in Vol. IX of the Tenth U. S. Census, to Dr. B. E. Fernow, to Mr. Raphael G. Zon for suggestions and for technical revision, to the Northwestern Lumberman and other trade journals, to many dealers, who have been uniform in their courtesy, and incidentally to Mr. Morris K. Jesup, whose magnificent collection of woods at the New York Museum of Natural History has been available to the writer as to others. These, with other sources of information acknowledged by the writer, and suggested to others, are suitably arranged in the following list. Of the 155 illustrations, 138 are original, the drawings having been prepared under the supervision of the writer from actual specimens by Mr. Irving T. Worthly of Cornell University and several students of New York University, and the photographs by Mr. John Hopfengartner, Jr., of Westchester, New York City. Other illustrations are, so far as possible, acknowledged in place.

TABLE OF CONTENTS.

LIST OF PLATES.

BIBLIOGRAPHY.

NAMES AND LOCALITIES.

"Check List of Forest Trees of the United States, their Names and Ranges," Sudworth. (U. S. Forestry Bulletin No. 17.)

FEATURES OF TREES, BOTANIES.

Prof. Sargent's "Silva of North America"; Michaux and Nuttall's "North American Silva"; Apgar's "Trees of Northern United States"; Publications U. S. Forestry Division; "Our Native Trees," Keeler; "Familiar Trees," Mathews; "Timber Trees and Forests of North Carolina," Pinchot & Ashe (N. C. Geological Survey Bulletin No. 6); "Report on Trees and Shrubs of Massachusetts," Emerson; "Manual of Botany," Gray; "Plants," Coulter; "Illustrated Flora of U. S.," Britton and Brown; etc., etc. Botanical Gazette; Guide to Trees and Shrubs of New England by their Leaves, Bradley Whidder, Boston.

COLOR, APPEARANCE OR GRAIN OF WOOD.

Jesup Collection at Museum of Natural History, New York City; Hough's American Woods (sections).

STRUCTURAL QUALITIES AND USES OF WOODS.

"Timber," Roth (Bulletin No. 10, U. S. Forestry Div.); Vol. IX, Tenth U. S. Census; Prof. Sargent's "Catalogue Jesup Collections"; Prof J. B. Johnson's "Materials of Construction"; Prof. Thurston's "Materials of Engineering," Part I; Dr. F. E. Kidder's "Inspection of Materials and Workmanship." Allusions in numerous publications U. S. Forestry Division.

WEIGHTS AND MODULI.

Circular No. 15, U. S. Forestry Division; Prof. J. B. Johnson's "Materials of Construction"; Mr. S. P. Sharpless' Tables for the U. S. Census (Vol. IX, Tenth Census; also Executive Document No. 5, 48th Congress, 1st Session, and also Sargent's "Catalogue Jesup Collection"); Prof. Lanza's "Applied Mechanics."

AMERICAN SPECIES.

See foot-notes to species in question.

FOREIGN SPECIES.

Thos. Lazlett's "Timber and Timber Trees"; Report on Forests of Western Australia by J. Ednie Brown; Catalogue Kew Botanical Gardens, London; Works Baron Ferd. von Mueller; "American Lumber in Foreign Markets" (Special Consular Reports, Vol. XI, U. S. State Dept.); Stevenson's "Trees of Commerce"; also see foot-notes, species in question.

GENERAL.

"Forestry for Farmers," Fernow, and other U. S. Forestry Division Publications, Vol. IX, Tenth U. S. Census; Hough's American Woods (text); The Forester; The Northwestern Lumberman; The (New Orleans) Lumber Trade Journal; The New York Lumber Trade Journal; The Timber Trades Journal (London); "Lumber Trade of U. S." (Bureau Statistics U. S. Treas. Dept.); Trees in Winter, Huntington.

HISTORICAL.

Brockhaus, Konversations-Lexikon; Pliny, etc.

MEDICINAL PROPERTIES.

U. S. Dispensatory.

Books particularly useful to beginners are in italics. Names are repeated when books could not be particularly classed under one heading. Also see foot-notes under subjects in questions.

INTRODUCTION.

[p001]

A tree has been defined as a woody plant that produces naturally and in its native place one principal erect stem with a definite crown of foliage. A plant thus attaining to the dignity of a tree is said to be arborescent.[1]

There are nearly five hundred distinct species of trees growing in the United States,[2] as well as many others peculiar to other countries, yet the great mass of wood everywhere utilized is derived from comparatively few of them.[3] Many woods will be more generally employed as their valuable properties become more familiar or as the supplies of wood now utilized continue to diminish.

The same tree is often called by different common names in different places. Nearly thirty names are thus applied to the longleaf pine (Pinus palustris). Such confusion can be avoided only by regarding the recognized botanical nomenclature.

The botanical name of a plant consists of two principal terms denoting genus and species. Quercus, for example, is [p002] the generic name including all species of oak. Alba, rubra, and others are specific names denoting the said species. Quercus alba and Quercus rubra are completed terms. Genera are not fixed but differ with authorities, so that the abbreviated name of the botanist responsible for the classification adopted is often added, as Quercus alba Linn. and Ulmus fulva Michx.

A species is a collection of individuals that might well have sprung from some single root. A genus is a collection of related species. Genera are gathered into families. Families and genera differ with authorities. A variety includes individuals differing slightly from accepted species. Its name when existing is part of the specific name. "Quercus robur var. pedunculata" specifies a variety (pedunculata) of "red" or strong (robur) oak (Quercus). A variety of one botanist is sometimes a distinct species of another.

The size and character of the trunk, and the range, locality, or distribution of the tree, have much to do with the utility of the wood, since large or perfect timbers cannot be derived from species characterized by small or crooked trees, and since wood is always more used if it is widely distributed so as to be easily available.[4]

Fig. 1.—Some Wood Elements.

Wood is made up of cell-structures; as, the true fibre, which originates from several cells; the tracheid (tra-ke-id), which originates from one; the vessel, which is a short, wide tube joined vertically end to end with others of its kind; the pith-ray; the resin-duct, and others,—all of which are often popularly referred to as fibres. [p003]

The character and the arrangement of cell-structures differ with species. Wood is hard, soft, light, heavy, tough, porous, elastic, or otherwise, because of these differences. Appearance is affected, and woods may be distinguished from one another, because of this fact.[5]

Most wood is used in "construction," that is, in mines, railways, houses, and ships, where demand is for size or quantity, and where finish and appearance amount to but little. Much wood is used in decoration and furniture, where appearance, appropriateness, and finish are called for; but these woods, although much in evidence, are infinitely less in quantity than those employed in construction. Some wood is required for implements, turnery, carvings, and small-piece work, where size is secondary and where qualities such as hardness, fine grain, and uniformity, controllable in small pieces, are primary. Some wood is used indirectly, as in the manufacture of paper-pulp, gunpowder, and chemicals. There are also by-products of trees, such as tanbark, turpentine, resin, nuts, and sugar.

The weight, strength, and other measurable properties of wood are variable. Weight varies from day to day as water is absorbed and evaporated. Strength differs with grain, age, moisture, specific gravity, and many other things. Two pieces from different portions of the same tree differ from each other. The proportions of sap and heart wood are seldom constant. Results from small specimens may differ from those obtained from larger ones. [6] The botanical accuracy of a specimen is not always certain, therefore figures relating to the physical properties of wood should be employed with greater caution than those relating to the more homogeneous metals.

Many of the experiments conducted to establish statements regarding the physical properties of wood have been defective [p004] in that while the conclusions were correct as applied to the specimens immediately studied, such specimens did not stand for the species at large. The recognition of difficulties, the selection of specimens, the scientific standardizing of methods so that results could be generally utilized, as distinct from the simple manipulation of specimens in testing-machines, have not been exhaustively attempted until recently. [7]

The experiments that have been made to determine the strength of woods may be grouped into the four following divisions:

The figures established by the United States Division of Forestry and alluded to in item 1, page 4, appear, so far as they exist, upon the following pages. Where they do not exist, the leading spaces set apart for them are left vacant for other insertions as preferred. All coefficients are in pounds per square inch. Fractions of pounds in weight and lower figures in coefficients have been omitted as superfluous.

It is not always easy to determine the species of living trees, because forms in the forest differ from those in the open, because bark varies with age, and because fruit and leaves of many trees are lacking in the winter. It is easier to tell genus than species—that a tree is an oak, than whether it is a red or a pin oak. Experience is required in this connection.

Trees are divided into two general divisions known as Exogens and Endogens.[8] [p007]

PLATE 2. EXOGENOUS STRUCTURE IN WOOD.
Yearly Rings or Layers.

A section of a Longleaf Pine Tree.

A section of Oak showing "porous" structure in yearly layers. (Natural size.)

A section of Hard Pine showing "solid" structure in layers. (Natural size.)

EXOGENOUS TREES. (Dicotyledons.)

Exogenous trees are those the trunks of which are built up by rings or layers, each deposited consecutively upon the outside of the others. A section exhibits first a central point or canal known as a pith-cavity, next and consecutively the annual layers, and finally the bark. The woods of this series are familiar to all. The oaks, pines, and practically all of the merchantable lumbers are among them. The forests are widely distributed, and the species are so numerous as to present an almost infinite range of possibilities.

Fig. 2.—Section Boxelder, showing Pith-cavity at Centre.

The young wood of exogenous trees is porous. It permits the passage of sap and is known as sapwood (Alburnum). As a layer is enclosed by others and retreats from the surface of the tree, it becomes denser, its canals are filled with gums or tannin, color changes, and the result is heartwood (Duramen). This change goes forward rapidly in some trees, such as locusts, so that their sections appear to be almost wholly heartwood; other species require longer time, and sapwood then predominates.

Heartwood gives stability to the tree, but is not needed in its physiological processes. It is tougher, heavier, stronger, and more valued in construction. Sapwood is vitally essential to the life of the tree, but is lighter, weaker, less durable, and less valued in construction. Sapwood is pliable, and the sapwoods of several trees are valued for this reason.

Wood-making varies as it takes place in the springtime and in the summer. Consequent differences in the densities [p008] of the deposits serve to mark the limits of the yearly rings. Some species, as the oaks and hickories, show pores throughout their spring woods which thus contrast with denser summer growths. Others, as Southern pines, change sharply, and their spring and summer growths appear as solid bands. In even climates, where seasons are not pronounced, growth is more regular and layers correspondingly less definite.[9]

The cellular structure of wood is principally vertical, a fact that explains the ease with which wood is split up and down. Beside the vertical, there are horizontal cells, that cross the tree, strengthen and bind the vertical cells, and assist in the life-processes of the tree. These horizontal cells form what are known as medullary or pith-rays and appear as simple lines or glistening plates according to the way in which the wood is cut. Woods differ in the size and number of these rays, which are by no means always visible to the eye (see plate 3).

Fig. 3.

Woods are easy or difficult to work in proportion as their fibres are arranged in a simple or a complicated manner. This is shown in the figures on plate 4. A knife pressed upon the oak must crush or cut into the fibres themselves, whereas with the pine it finds some natural passage between the cells. Wood may be cut so as to develop cross-sections (C, Fig. 3), radial sections (R), or tangential sections (T). The respective [p009] markings are in a general way indicated on the boards in the figure.

PLATE 3. EXOGENOUS STRUCTURE IN WOOD.
Medullary or Pith Ray.

Middle--Actual appearances of pith ray, PP.

Bottom--Microscopic enlargement of a tangential section of White Oak showing large pith ray, pp.

PLATE 4. EXOGENOUS STRUCTURE IN WOOD.
(CROSS-SECTIONS, ENLARGED.)

Top--Two yearly layers of White Oak. The larger pores were formed in spring, the smaller ones in summer. The small circles are ends of fibres. A knife pressed upon this surface would crush or cut into the cells. The mass would not split or separate evenly.

Bottom--Two yearly layers of White Pine. The space in the outer or darker one is a resin-duct; the circles are ends of fibres (tracheids); pith rays are noticeable. A knife pressed upon this surface would find easy passage. The mass would separate easily.

Logs are sometimes sawn into quarters and then into pieces crossing and exposing the yearly rings. (See Fig. 4.) These "quarter-sawn" surfaces are structurally stronger and better, but are, by reason of waste or small pieces, more costly than others. The pith-rays of some woods, such as oaks, are very prominent when split as they are in "quarter-sawing," and the appearance of such woods is consequently improved.[10]

Fig. 4.

Exogenous trees are divided into broad-leaved trees and needle-leaved conifers. The broad, flat leaves of trees such as oaks and chestnuts gave rise to the former term, while the narrow resinous leaves of the pine and hemlock gave rise to the latter. The woods of the former group are usually referred to as hard woods, although some of them are very soft; those of the latter group are referred to as soft woods, although some of them are very hard. Most, but not all, of the broadleaf trees are deciduous, that is, they change their foliage every year; and most, but not all, of the needleleaf trees are evergreen, that is, the foliage is persistent. Needleleaf trees are also known as conifers, that is, cone-bearers.

It is usual to associate the terms broadleaf, deciduous, and hard wood; and likewise the terms needleleaf, conifer, evergreen, and soft wood. While generally correct, this is, as seen, not always so. A better division is into broadleaf trees or woods, and needleleaf conifers. [p010]

BROADLEAF WOODS.

The trees affording these woods are found in natural forests and under cultivation in nearly every portion of the globe. The histories of some of them extend back to very remote periods. Their woods were the principal ones in construction until the advent of American soft woods. The oaks, elms, maples, and other so-called hard woods are of this group.

Broadleaf woods are characterized by complex fibre conditions, absence of resins, and greater weights.[11] They are composed of several kinds of cells and fibres, arranged without the regularity so noticeable in the conifers. Cross-sections exhibit numerous, often easily visible pores, arranged in zones or scattered throughout the rings (see plate 2). Pith-rays are numerous and more or less conspicuous, save in softer hard woods such as poplar. Woods are difficult to work in proportion as they are complicated in structure. The numerous members of the group vary from one another and present an extensive range of properties. Trees do not usually afford large pieces. Woods for cabinet work, implements, and other fine purposes are from this group. The total requirement is less than for needleleaf woods.

The leaves of broadleaf trees are easily distinguished from the resinous, usually evergreen ones of the conifers. Most of them are deciduous, that is, shed every season, although some are persistent, that is, "evergreen." "Broadleaf," "deciduous," and "hardwood" trees are the same. [p011]

PLATE 5. WHITE OAK (Quercus alba).

OAK. (Quercus.)

The oaks are found on all of the continents of the northern hemisphere, as well as at high altitudes just south of the equator. Their woods stand pre-eminent among those of the broadleaf series and have been highly prized from early periods. Formerly relied upon for all purposes of house and naval architecture, they did not give way to the so-called "soft woods" for houses, and to iron for vessels, until comparatively recent periods. They were supplanted for the former purposes upon the opening of the soft-wood forests of North America and of the Baltic, and for vessels subsequent to the conclusions of the American Civil War.

White Oak
(Quercus alba).

The historical importance of oak is founded upon the reputation of the English Oak as derived from two trees, Quercus robur var. pedunculata and Quercus robur var. sessiliflora, usually taken as sub-species of Quercus robur.[12] It is said that these trees once formed large forests over Northern and Central Europe. Live-oak has always been highly esteemed, but is now very scarce. It is one of the hardest, heaviest, and most durable of constructive woods and was once largely employed in ship-building. The wood of the White Oak (Quercus alba) is at present preferred for most purposes for which oak is now employed, and is one of the most valuable of the American hard woods.

Red Oak
(Quercus rubra).

Oak is tough, durable, easily obtained, liable to warp and check in seasoning, often hard to nail without splitting, susceptible of high polish, and not greatly liable to attack by insects. It contains gallic acid, causing peculiar taste and odor and attacking iron, the solutions staining the wood. Experiments[13] indicate that iron fastenings are shortly protected by an insoluble scale of resulting salt, and that the wood, although [p012] darkened, remains practically uninjured. The later oaken vessels were iron-fastened,[14] and cabinet-makers now employ that metal in joining oak. The barks of all species are also so charged with acid as to be used in the tanning of leather. The several kinds of oak are commercially divisible into three general groups, white oak, red or black oak, and live oak.[15] The principal species affording woods under each head are as follows:

Live Oak
(Quercus virginiana).

Oak trees are characterized by oblong, thin-shelled kernels, protruding from hard scaly cups and called acorns. The foliage is sometimes deciduous and sometimes evergreen. Most oaks require many years to reach maturity, but are then long-lived. Fifty of the nearly three hundred known species of oak are natives of the United States and Canada; all but four become trees under favorable conditions. Quercus is from two Celtic words, quer, signifying fine, and cuex, a tree. [p013]

White Oak. Quercus alba Linn.

Nomenclature.

Locality.

Features of Tree.

Color, Grain, or Appearance of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

Cow Oak. Quercus michauxii Nutt.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

Chestnut Oak. Quercus prinus Linn.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

Post Oak. Quercus minor Sargent, Quercus obtusiloba Michx.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

Bur Oak. Quercus macrocarpa Michx.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

White Oak. Quercus garryana Douglas.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

Red Oak. Quercus rubra Linn.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

Pin Oak. Quercus palustris Muenchh.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

Spanish Oak. Quercus digitata Sudworth, Quercus falcata Michx.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

Black Oak, Yellow Oak. Quercus velutina Lam. Quercus tinctoria Barti.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

Live Oak. Quercus virginiana Mill. Quercus virens Ait.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

California Live Oak. Quercus agrifolia Nee.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

Live Oak. Quercus chrysolepis Liebm.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

English Oak. Quercus robur var. pedunculata.

Nomenclature.

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

PLATE 6. WHITE ASH (Fraxinus americana).

ASH. (Fraxinus.)

Ash is widely distributed over the temperate regions of the northern hemisphere, and occurs in the tropics, on the island of Cuba. The tree has occupied a position second only to that of oak. Our Teutonic forefathers relied upon its wood for boats and weapons. Their ancient faith connects it with the creation of the original man. It is often associated with oak in country proverbs.[21] Europeans regard the trees for ornamental purposes, but Americans value them for wood.

White Ash
(Fraxinus americana).

Ash and oak woods resemble one another in that there are bands of open pores in both woods, but the pith-rays of the ash are thinner and scarcely discernible. Ash is coarser, less attractive, easier to work, tough, elastic, and somewhat lighter than oak. It seasons well, but does not last when exposed to the weather. Lumbermen separate the woods into white and black ash, the former including the lighter-colored and more desirable pieces. This commercial division is also a botanical one in the North, where the only species of any note are the white ash and black ash (F. americana and F. nigra). The Southern green ash (F. lanceolata) is usually classed as white ash. The trees that grow up after the cutting of the virgin forest afford tougher, more pliable, but not necessarily stronger pieces, known as "second-growth" ash. Although not relied upon for out-of-door construction, ash is one of the most important of the cheaper cabinet woods and is used in stairs, furniture, and similar works. [p028]

One half of the thirty known species of the genus Fraxinus inhabit North America. [p029]

White Ash. Fraxinus americana Linn.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

Red Ash. Fraxinus pennsylvanica Marsh. Fraxinus pubescens Lam.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

Blue Ash. Fraxinus quadrangulata Michx.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

Black Ash. Fraxinus nigra Marsh. Fraxinus sambucifolia Lam.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

Green Ash. Fraxinus lanceolata Borkh. Fraxinus viridis Michx. f.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities.

Representative Uses.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

Oregon Ash. Fraxinus Oregona Nutt.

Nomenclature.

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

PLATE 7. ELM (Ulmus americana).]

ELM. (Ulmus.)

The different species of elm are distributed over the cold and temperate portions of the northern hemisphere, save western United States and Canada. A high degree of perfection is attained in eastern North America, where trees are greatly prized for their form and appearance.

ELM (Ulmus americana).

The foliage of the elm is concentrated at the top, and the absence of lower branches causes it to be a good tree to plant near houses or along streets. Much of the wood is tough, fibrous, durable, strong, hard, heavy, and, because it is so often cross-grained, difficult to split and work. The large pores of the spring wood arranged in one or several rows mark the annual deposit, while the minute pores of the summer wood arranged in concentric wavy lines are so peculiar as to distinguish this wood from all others. The tall, straight trunks afford pieces of considerable size. Elm piles sustain constant and severe shocks for long intervals. The grain arrangement of elm is often very beautiful, so that it is increasingly used for decoration. It is more commonly employed in the construction of cars, wagons, boats, agricultural implements, machinery, and furniture.

The shape of the trees is so marked as to cause them to be easily noted. Fifteen or sixteen species have been recognized. Five are known to exist in the eastern American forests, and all of them furnish good wood of commercial importance. Ulmus was the ancient name of the elm. [p036]

White Elm. Ulmus americana Linn.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

Cork Elm. Ulmus racemosa Thomas.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

Slippery Elm, Red Elm. Ulmus pubescens Walt. Ulmus fulva Michx.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

Wing Elm, Winged Elm. Ulmus alata Michx.

Nomenclature.

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

MAPLE. (Acer.)

The maples grow on all of the continents of the northern hemisphere. Nearly one half of the known species belong in China, Japan, and the Orient. The principal European species (Acer pseudo-platanus) is the European sycamore.[25] The hard or sugar maple (Acer saccharum) is one of the principal deciduous trees of North America.

Maple wood[26] is characterized by its appearance and by its fine compact texture. The first quality is so marked that selected pieces take rank among the most beautiful of cabinet woods; the last is so pronounced as to fit it for carvings and even for type. "Birdseye," "blister," and "curly" maples are not from different species, but are the results of fibre distortions, possible in some form in any tree of any species, but peculiarly liable to occur in the maple; birdseye and blister effects for the most part in the hard maples, curly effects in the hard, but generally in the softer, species. The distortions do not occur in all trees, and it is seldom possible to tell whether the woods are thus figured until after the trees have been cut. Maple wood shrinks moderately, stands well in protected places, is strong, tough, but not durable when exposed. Pores are not arranged in circles, but are scattered irregularly throughout the layers. Maple is used for ceiling, flooring, panelling, car and ship construction, shoe-lasts, shoe-pegs, furniture, school supplies, implements, and machinery. Sugar is principally, although not exclusively, present in the sap of the sugar maple.[27] The softer species are sometimes [p041] tapped, and sugar is also present in the sap of other trees, such as the butternut and birch. A sugar maple will, on an average, produce about twenty-five gallons of sap, containing a total of about six pounds of sugar, in a season.

PLATE 8. SUGAR MAPLE (Acer saccharum).

Bottom--"Curly" Maple Wood (dissection).

a, Box Elder. b, Hard or Sugar Maple. c, Soft or Red Maple. d, Soft or Silver Maple.

The Boxelder (Acer negundo) is a true maple, remarkable in that it is widely distributed from Canada to Mexico and from the Atlantic to the Rocky Mountains, on low bottom lands, and at elevations of five thousand and six thousand feet.[28] The trees are beautiful and, like other maples are valued for ornamental purposes. The soft, light wood is not particularly noted, although occasionally used for woodenware, interior finish, and paper-pulp. Small quantities of sugar are present in the sap of this tree.

The maples may be told by their leaves of characteristic shape, but chiefly by their two-seeded fruit or "keys," the two wings of which spread differently in different species. The leaves of some species change in autumn from green to red and other brilliant colors. Those of other species change to yellow without trace of red. Sixty to seventy species have been distinguished, nine of which occur in North America. [p042]

Sugar Maple, Hard Maple. Acer saccharum Marsh. Acer saccharinum Wang.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

Silver Maple, Soft Maple. Acer saccharinum Linn. Acer dasycarpum Ehr.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

Red Maple, Swamp Maple. Acer rubrum Linn.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

Oregon Maple. Acer macrophyllum Pursh.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

Boxelder, Ash-leaved Maple. Acer negundo Linn. Negundo aceroides Moench.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

PLATE 9. WALNUT (Juglans).

Black Walnut Tree (Juglans nigra).	Black Walnut Trunk (Juglans nigra).
Black, White, and English Walnuts.	Black Walnut Wood (Juglans nigra).

WALNUT. (Juglans.)

The English or Royal Walnut (Juglans regia), a native of Persia, was the only available species of this genus until the introduction of the nearly similar Black Walnut of North America.[29] As oak gave way first to soft woods for construction, so it gave way first to walnut for cabinet purposes. The wood soon became very fashionable, and exorbitant prices were paid for it. Walnut was extremely popular in the United States until about 1880, when oak began to resume its place as the popular cabinet wood. The nuts of the English or Persian walnut are better than those of the American species, but the wood of the latter is superior.

The use of walnut wood for gun-stocks began in Europe, the demands early becoming so great that, until the general peace following the battle of Waterloo, the greater part of the French product was diverted for that purpose, while prices rose in England so that six hundred pounds sterling is reported to have been paid for a single tree. In spite of the innumerable woods that have since been introduced, this one is yet regarded as best for gun-stocks.[30] Walnut is a firm, hard, chocolate-colored wood, with pores not arranged in rings but scattered somewhat irregularly. The sombre, although rich, color has been objected to for some positions. Large excrescences or "burrs" are common on foreign trees, particularly those near the Black Sea and in Italy. The grain in such growths is beautifully irregular, and the wood, known as "burl," is prized for veneers. Trees are very scarce, and walnut is now seldom seen save in cabinet work or gun-stocks. The related White Walnut or Butternut (Juglans cinerea) affords a less-prized and [p048] lighter-tinted wood. The nuts of the walnuts are a source of profit.

Black walnut trees seldom form forests by themselves, but occur generally in mixed growth. They grow quickly, but the heartwood for which the tree is valued begins to form only when the tree is at a considerable age, so that a number of years must elapse before a tree can produce wood of the desired quality. Trees one hundred years old furnish the best quality of wood.

Walnut trees may be known by their nuts, the husks or pods of which adhere unbroken, instead of loosening, completely divide into four sections, as with the hickories. Juglans is from Jovis, signifying Jove's, and glans, signifying acorn. This nut, not the fruit of the oak, was the acorn of the ancients.[31] [p049]

Black Walnut. Juglans nigra Linn.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

Butternut, White Walnut. Juglans cinerea Linn.

Nomenclature.

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

PLATE 10. HICKORY (Hicoria ovata).

HICKORY. (Hicoria or Carya.)

The Hickories occur only in the eastern part of North America. They produce woods in which the qualities of toughness, elasticity, and resilience are unusually pronounced, and since these qualities are greatest in the sapwood, hickories are peculiar in that the sapwood is more valuable than the heart. Second-growth wood is much prized, since, being younger, it contains more of the pliable sapwood.[32]

Hickory is not durable when exposed and is more or less subject to attack by boring-insects. It is used for implements, machinery, carriages, and the like; hickory axe-helves have no superiors. The nuts of the shagbark or white hickory are a source of considerable profit. The pecan (Hicoria pecan) affords wood so inferior as to be little used in construction, although it makes an excellent fuel. Pecans are planted in many of the Southern States because of the nuts, for which a considerable demand exists.

The Hickories are known by their nuts, the husks or pods of which loosen completely from the nut in four pieces, instead of adhering unbroken as in the case of the walnuts. The nine species are American trees, eight of them being natives of the United States. Carya was the Greek name of the common walnut. Hickory is said to be derived from the Indian powcohicora, a liquor once obtained from the nuts of the hickory. [p052]

Shagbark Hickory, Shellbark Hickory. Hicoria ovata Mill. Carya alba Nutt.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

Pignut (Hickory). Hicoria glabra Mill. Carya porcina Nutt.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

Mocker Nut (Hickory). Hicoria alba Linn. Carya tomentosa Nutt.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

Pecan, (Hickory). Hicoria pecan Marsh. Carya olivæformis Nutt.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

CHESTNUT, CHINQUAPIN. (Castanea.)

The chestnut is found in the temperature regions of central and southern Europe, northern Africa, China, Japan, and eastern North America. The wood is valued in construction, and the much-prized nuts are regarded as a food rather than a confection. European chestnut wood was once high in favor, although examination of structures in which it was supposed to have been used indicates that in some instances oak had been mistaken for it and had been employed in its place.

The North American chestnut affords a weak, brittle, but easily worked and very durable wood, such as is admirably adapted for beams, ties, and sills, where lightness and durability rather than much transverse strength are required. Trees in Europe have attained to great size and age. Micheaux mentions one thirty feet in circumference six feet from the ground and said to have been standing for a thousand years. The famous Mt. Etna chestnut[37] is reported to have measured two hundred and four feet in circumference. Large trunks are apt to be hollow, affording brittle, useless wood. The botanical relation between the American and European chestnuts is not distinct. Some consider the former a distinct species, others a variety only. The name "Chinquapin" applies to two distinct botanical species, one, the Castanea pumila, closely related to the common chestnut; the other, Castanopsis chrysophylla, belonging to the same family (Cupuliferæ), but to quite another genus. Both afford woods resembling, but heavier than, chestnut.

PLATE 11. CHESTNUT (Castanea dentata).

Top-Left--(Courtesy N. C. Geological Survey.)

The chestnut may be known by its large prickly burr, [p057] containing from one to three thin-shelled, triangular, wedge-shaped nuts. Both chinquapins have prickly burrs containing one, or sometimes two, sweet edible nuts. Three of the four known species of the genus Castanea grow in North America, one the common chestnut (Castanea vulgaris); another the Chinquapin (Castanea pumila); the third a plant never attaining to the size of a tree. The Chinquapin (Castanopsis chrysophylla) is the only North American representative of a genus including twenty-five species. Keeler says that Castanea is from a town of that name in Thessaly, or from another town of that name in Pontus. [p058]

Chestnut. Castanea dentata (Marsh) Borkh. Castanea vesca var. americana Michx. Castanea vulgaris var. americana A. de C.

Nomenclature.

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

Chinquapin. Castanea pumila (Linn.) Mill.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

BEECH.(Fagus.) IRONWOOD.(Carpinus, Ostrya, etc.)

Beech is well known on the eastern continent. The common beech (Fagus atropunicea) is the only American representative. Eastern species have figured in literature since the time of Virgil. The northern nations early wrote upon thin tablets of beechwood, and boc, bok, and buche, the northern names for beech, finally gave origin to the word book.[38] American Indians believed that the beech was proof against lightning.

Beech (Fagus atropunicea).

Beechwood is hard, heavy, strong, not durable when exposed, and somewhat subject to attack by insects. European engineers employ it to a considerable extent in construction, but it is seldom used in America save for indoor finish, furniture, handles, flooring, and the like. The small edible nuts, known as beech-mast, are pressed abroad for a fixed oil, resembling and used in place of that from the olive. They are seldom gathered in this country, but are devoured by animals. Beech-trees have smooth, light-colored bark, and are very attractive in their winter appearance. They may be recognized earlier in the season by their small prickly burrs, each containing two triangular, sharp-edged nuts. There are fifteen or more species known to belong to this genus. Fagus is from phago, to eat, and refers to the nut.

PLATE 12. BEECH (Fagus).

The name Ironwood has been applied to Blue Beech (Carpinus caroliniana), to the Hornbeam (Ostrya virginiana), and to at least eight other North American species affording unusually hard and heavy woods, such as are used for handles [p061] and implements.[39] Trunks of trees affording these woods are generally small and the weight of the woods is so great as to prevent their use in construction. [p062]

Beech. Fagus atropunicea (Marsh.) Sudworth. Fagus ferruginea Ait.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

Ironwood, Blue Beech. Carpinus caroliniana Walt.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

Ironwood, Hop Hornbeam. Ostrya virginiana Willd.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

PLATE 13. SYCAMORE (Platanus occidentalis).

Quartered Sycamore Wood.

SYCAMORE. (Platanus.)

The name Sycamore applies to a maple (Acer pseudo-platanus) in Europe, to a fig-tree (Ficus sycomorus) in the Orient,[40] and to the buttonball or plane tree (Platanus) in North America. Of the plane trees (Platanus) the common or Oriental plane (Platanus orientalis) is a native of Europe; the plane, buttonball, or sycamore tree (Platanus occidentalis) is a native and common tree in eastern North America; and the California plane, buttonball, or sycamore (Platanus racemosa) is a native of western North America.

Sycamore (Platanus occidentalis).

The sycamore stands for curiosity, because of its Biblical association with Zaccheus. Many European sycamores were planted by religious persons during the middle ages because of the belief that they were the trees thus referred to in the Bible.

The woods afforded by the American sycamores have unusually complicated, cross-grained, but beautiful structures, difficult to work, but standing well and valued for cabinet work and small articles. American trees are often very large.

American buttonball or sycamore trees are distinguished by rough balls which remain hanging on long stems throughout the winter. The bark also is shed to an unusual extent; flakes of the outer cover drop away, exposing smooth inner surfaces so white as to appear as if painted. Six or seven species are included in the genus; three occur in North America. Platanus is from platus, signifying broad, and refers to the shape of the leaves. [p066]

Sycamore. Buttonwood. Buttonball-tree. Platanus occidentalis Linn.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

California Sycamore. Platanus racemosa Nutt.

Nomenclature.

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

BIRCH. (Betula.)

The birches grow in Europe, Asia, and North America, their ranges on the latter continent extending far into the north.[42] Their history is remote and probably began with attention to the bark rather than to the wood.

Birch-bark is smooth, pliable, water-tight, and by reason of its resinous oils so durable that it often remains intact long after the wood inside of fallen trees has disappeared. It is separable into thin layers and was early employed as a writing material.[43] Houses have been covered by it and it has been used for cordage, utensils, "damp courses," and even rude clothing. The American Indians employed it for canoes, tents, troughs, and buckets. The wood is hard, heavy, strong, fine-grained, and beautiful. It shrinks in seasoning, works easily, stands well when not exposed. It is used for spools, woodenware, and other small articles, as well as for interior finish and cabinet work. Figured birch is one of the most beautiful of American cabinet woods.[44] Birch is often stained so as to imitate cherry and mahogany; the best imitations of the latter wood are of birch. Birch is commercially divided, according to the quantity of heartwood present, into white birch and red birch. The wood is "white" when the amount is small, and as heartwood increases with age the same tree might at one time afford white and at another red wood.

Birch trees may be known by their more or less laminated bark with its peculiar long horizontal lenticles or dashes. The [p069] leaves of the several birches differ but little, but the decided colors exhibited by their barks give names and serve to distinguish the species. Nine of the twenty-four known species of birch occur in North America; six are trees and the others low shrubs. Betula is said to be derived from bitumen. [p070]

PLATE 14. BIRCH (Betula).

Yellow Birch Tree (Betula lutea).	White Birch Bark (Betula populifolia).
Yellow Birch Foliage (Betula lutea).	Birch Wood.

White Birch. Betula populifolia Marsh.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Grain, or Appearance of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

Paper Birch, White Birch. Betula papyrifera Marsh.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Grain, or Appearance of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

Red Birch. Betula nigra Linn.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

Yellow Birch. Betula lutea Michx. f.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

Sweet Birch, Cherry Birch. Betula lenta Linn.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

PLATE 15. LOCUST (Robinia, Gleditsia).

Black Locust Tree and Bark (Robinia pseudacacia.)
	Honey Locust (Gleditsia triacanthos).
Locust Wood.

LOCUST, MESQUITE. (Robinia, Gleditsia, Prosopis.)

The name Locust applies to species of three distinct genera, all of which belong to the family Leguminosæ. The black locust (Robinia pseudacacia), the honey locust (Gleditsia triacanthos), and the Mesquite or honey locust (Prosopis juliflora) are principal representatives of their respective kinds. The first-named genus is North American, the other two have species on both continents.

BLACK LOCUST (Robinia pseudacacia).

Black locust wood is tough, durable, unequalled for torsional strength and resilience, and is in every way in the first rank of American woods. It is fitted not only for exposed constructions, but for finer articles; hubs, pins, bolts, and trenails having no superiors. Trees develop rapidly when young, heart wood forming as early as the third year. Later growth and ultimate commercial value in the United States are much affected by insect borers, which practically limit the usefulness of the species. The black locust may be known by its clusters of large pea-blossom-shaped flowers, its bean-shaped pods, three to six inches in length, and by the prickles on the bark. The genus has six species, four of which are natives of the United States.[45] Robinia is from Robin, the name of an early French botanist. [p076] The black locust has been extensively introduced into Europe, both for ornamentation and for wood.[46]

The wood of the honey locust resembles that of the black locust, but is seldom used or appreciated save for fencing and similarly unimportant purposes. Trees grow rapidly and are not subject to the attacks of insects, so that they frequently attain to normal proportions. The flowers are much smaller than those of the black locust, but the pods are several times as long (twelve to eighteen inches). These often curl in drying and are thus rolled to some distance by the wind. Thorns or spines are present on some individuals and are often from three to six inches in length. The foliage resembles but is more delicate than that of the black locust. There is at least one other American species. Gleditsia is from Gleditsch, the name of a botanist.

Mesquite, also called honey locust, affords wood that is hard, heavy, and almost indestructible in exposed positions. The tree grows in the desert where vegetation would often seem to be impossible. The roots are developed to great size by their search for water, and are gathered and burned in the absence of other fuel. The trunks are small, but afford posts and ties. There are pods filled with rich edible pulp. Sixteen or more species belong to this genus, prosopis, of which one other, the screw-pod mesquite (Prosopis odorata), is found in the United States. [p077]

Locust, Black Locust, Yellow Locust. Robinia pseudacacia Linn.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

Honey Locust. Gleditsia triacanthos Linn.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

Mesquite. Prosopis juliflora (Swartz) de C.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

WHITEWOOD OR TULIP-TREE WOOD (Liriodendron.), POPLAR OR COTTONWOOD (Populus.), CUCUMBER-TREE WOOD (Magnolia.), BASSWOOD (Tilia.).

These trees are not related, but are all noted for woods with soft, fine qualities, such as fit them for carvings, woodenware, and paper-pulp. No one of the woods is durable when exposed, and all are used for boxes because they nail without splitting. The names are commercially interchangeable.

Whitewood (Liriodendron tulipifera).

The whitewood or tulip tree (Liriodendron tulipifera) is a native of America and an acclimated tree in Europe. It is the sole surviving species of its genus. The wood is soft, stiff, clean, fine, straight-grained, and obtainable in large-sized pieces. Much whitewood is made into lumber, the wood standing among those of the broadleaf series as white pine does among the conifers. Whitewood is particularly suitable for carvings. In spite of its name it is largely greenish yellow. It is often divided commercially, according to color, into "white poplar" and "yellow poplar." Trunks often attain to a very large size. Matthews mentions a specimen[48] thirty-three feet in circumference. The species may be known by its large tulip-shaped flower. Liriodendron is from two Greek words meaning lily and tree.

PLATE 16. WHITEWOOD OR TULIP TREE (Liriodendron tulipifera).

The poplars, sometimes called cottonwoods because of their seeds covered with a cotton-like down, are represented on both continents. The wood was made into shields by the [p081] ancients, because it was light and tough and would indent without breaking. The wood is often substituted for whitewood, but is less desirable, although valuable as a basis for paper-pulp. The trees may be known by the long drooping catkins that appear early in the spring before the leaves, and that are followed by white downy seeds that soon escape to whiten the surrounding ground. The poplars are noted for foliage more or less constantly in agitation. This peculiarity, so pronounced in the aspen (Populus tremuloides), is due to the very long petioles or leaf-stems. The cottonwoods abound in many otherwise arid regions of American Western deserts.

The cucumber trees are of the magnolia family and grow in many of the Eastern States. The wood resembles and is probably often mistaken for whitewood, for which it is a fair substitute. The trees may be known by their fruit, which resembles vegetable cucumbers. Magnolia is from Magnol, a botanist of the seventeenth century.

Basswood is a name applied to trees known in Europe and America as limes, lime trees, lind, linden, tiel, tiel trees, bass, and basswood trees. The trees and their wood were early esteemed, the first for their shade and appearance, and the last for their working qualities, which resemble, but are inferior to, whitewood.[49] The trees are characterized by their dense foliage and clusters of small cream-colored fragrant flowers, so attractive to bees as to have originated the further name bee-tree. Tilia arises from the ancient name for these trees. [p082]

Tulip Tree, Whitewood, Yellow Poplar. Liriodendron tulipifera Linn.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

Poplar, Largetooth Aspen. Populus grandidentata Michx.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

Cottonwood. Populus deltoides Marsh. Populus monilifera Ait.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

Black Cottonwood. Populus trichocarpa Torr. and Gr.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

Cucumber Tree. Magnolia acuminata Linn.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

Basswood, Linn, Linden. Tilia americana Linn.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

WILLOW. (Salix.)

The willows are very widely distributed over both continents, and their history extends back over a very considerable period. Pliny states that Britons used to make voyages in boats of willow. The willow mentioned in the Bible was the Salix babylónica, or weeping willow, later acclimated in this country.

The principal experience with the tough, light, workable, elastic wood has been in Europe. The ancients used it for shields, because it was one of the woods that would indent without breaking. Lazlett states that it is used for cart-linings because it will not splinter when struck by stones. It has been used for lap-boards, cricket-bats, keels, paddles, and water-wheels. It resists heat and friction and is therefore used for lining friction-brakes. Willow charcoal ignites readily and is highly esteemed in the manufacture of the finer kinds of gunpowder. The bark is used in tanning. The little branches have long been associated with baskets and woven work. American trees are seldom cut up into lumber, but are valued for shade and appearance, and are often planted along the banks of streams to prevent erosion.

Willows grow very rapidly and have a characteristic and attractive appearance. They usually prefer low moist places. There are so many hybrids and peculiar species as to render classification in all cases difficult.[50] Black willow is the native species, oftenest attaining to tree size in North America. The White, Crack, Bedford, and Goat Willows (Salix alba, S. fragilis, S. russeliana, and S. caprea) are said to afford good wood. Salix is said to be from the Celtic sal, meaning near, and lis, water. Salicylic acid is abundantly present in the bark of some species. [p089]

PLATE 17. BLACK WILLOW (Salix nigra).

Black Willow. Salix nigra Marsh.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

CATALPA. (Catalpa.)

Many kinds of wood that were formerly plentiful are now much less so. Attention is being turned to trees that give best results under artificial conditions. Catalpa, formerly but little known, now bids fair to become of some importance in this connection.

The catalpa grows rapidly and produces a coarse, brittle, weak, but durable and desirable, lumber, well fitted to meet the requirements of railways and other branches of construction where the annual consumption is the largest. Fifty thousand catalpa trees have recently been planted by a Western railway at a cost of one cent apiece. Catalpas at Hutchison, Kansas, were large enough to cut for posts at the end of six years.[51] A sample tie recently removed from a Western railway was found to be perfect after fifteen years of service. Mr. John Brown[52] mentions specimens sixteen inches in diameter seventeen years after planting. The species Catalpa speciosa is said to be much the more desirable in that it is hardy and reaches a tall upright form.

The catalpa may be known by its showy flowers, suggesting those of the horse chestnut. These are succeeded by long pods filled with many-winged seeds and often used by children as cigars. [p091]

PLATE 18. CATALPA (Catalpa).

Catalpa, Hardy Catalpa. Catalpa speciosa Warder.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

Catalpa. Catalpa Catalpa (Linn.) Karst. Catalpa bignonioides Walt.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

PLATE 19. SASSAFRAS (Sassafras officinale).

SASSAFRAS. (Sassafras.) MULBERRY. (Morus.)

The sassafras was one of the first American trees to be described in Europe,[53] where many fictitious properties were early credited to its aromatic essences. The wood is not distinguished by unusual qualities, but trees are cut for lumber as encountered with other and more valuable species in the forest. The mucilaginous leaves are of three separate shapes. Some have lobes on both sides of the central surface, others have one lobe at one side so as to resemble mittens, while yet others on the same branch have simple oval shapes. The dark-blue berries on bright-red stems are so eagerly devoured by birds as to be seldom seen. The characteristic flavor is most pronounced in the bark of the root.

The Red, White, and Black Mulberries are named from the color of their fruits. The former, which is the American species, has wood resembling that of the sassafras, only in that it is not distinguished by unusual qualities. Its leaves, like that of the sassafras, are of several shapes on the same tree. The very sweet fruit resembles blackberries in form. The leaves used in silkworm-culture are from the Russian mulberry, a cross between the white mulberry and black mulberry (M. alba and M. nigra).[54] [p094]

Sassafras. Sassafras officinale Nees and Eberm. Sassafras sassafras (Linn.) Karst.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

Red Mulberry, Mulberry. Morus rubra Linn.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

BUCKEYE. HORSE CHESTNUT. (Æsculus.)

The buckeye and horse chestnut are species of the same genus. The common horse chestnut (Æsculus hippocastanum) was once thought to have been a native of Asia, but it is now quite certain that it originated on the mountains of northern Greece. Trees have been cultivated in Europe for at least three centuries and are now extensively grown over the United States. The name buckeye is generally applied to such species as are natives of North America.

Horse Chestnut (Æsculus hippocastanum).

The woods resemble one another in that they are soft, straight-grained, easily worked, and decay rapidly when exposed. They are employed to some extent in woodenware, artificial limbs, and paper-making. The trees may be known by their round prickly pods, containing smooth chestnut-colored bitter nuts. The leaves of the buckeye are arranged in groups of five, while those of the horse chestnut are in groups of seven. The horse chestnut produces showy spotted flowers. There are thirteen species of this genus, eight of which are North American. The name "horse chestnut" may refer ironically to the coarse nuts, or may arise from the fact that they are occasionally eaten by cattle, or from a horseshoe marking seen on young twigs. Hippocastanum is from hippos, a horse, and castanea, a chestnut. The name buckeye refers to the appearance of the brown nut through the paler husk partly separated when ripe, suggesting the eye of the common deer. [p097]

PLATE 20. HORSE CHESTNUT (Æsculus hippocastanum).

Ohio Buckeye, Fetid Buckeye. Æsculus glabra Willd.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

Buckeye, Sweet Buckeye. Æsculus octandra Marsh. Æsculus flava Ait.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, and Grain of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

PLATE 21. SWEET GUM (Liquidambar styraciflua).

GUM. (Liquidambar, Nyssa.)

This name is applied to two unrelated American trees—the Sweet or Red Gum (Liquidambar styraciflua), a member of the witch-hazel family, and the Sour or Black Gum (Nyssa sylvatica), which is one of the dogwoods.

The woods afforded by these two trees are also distinct from one another, although both are referred to by the one name, gum. The softer Sweet Gum figures in carpentry. Selected pieces so resemble black walnut as to be cut into veneers and made up into furniture. Sour Gum is harder, it splits with difficulty, and is fitted for small work and implements, such as wagon-hubs and tool-handles. Both woods are close-and often cross-grained, besides being strong, heavy, tough, and difficult to season.

Sweet Gum (Liquidambar styraciflua).

The Sweet Gum tree is characterized by rough, round balls, resembling those of the sycamore, by pointed star-like leaves, suggesting those of the sugar maple, and by corky ridges on the bark of younger branches. These latter cause the bark to resemble alligator-skin and give rise to the name alligator-wood. Liquidambar refers to gums excreted by the tree and sometimes used in medicine. The Sour Gum bears ovoid bluish-black sour drupes, or fruit containing single roughened seeds. The thick oval leaves are dark green above and dull or hairy below. The foliage of both species becomes brilliant in autumn. [p100]

Sweet Gum. Liquidambar styraciflua Linn.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

Sour Gum, Black Gum, Tupelo. Nyssa sylvatica Marsh.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

Cotton Gum, Tupelo Gum, Large Tupelo. Nyssa aquatica Linn.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

PLATE 22. HOLLY, BOXWOOD, LIGNUMVITÆ (Ilex, Buxus, etc.).

Box Tree (Buxus sempervirens).	Dogwood Foliage (Cornus florida).
Holly Foliage (Ilex opaca). Lignumvitæ Foliage (G. sanctum).	Dogwood Bark (Cornus florida).
Dogwood Wood.
Lignumvitæ Wood.

HOLLY (Ilex.). BOXWOOD (Buxus, Cornus, etc.). LIGNUM VITÆ (Guajacum.).

The woods afforded by these trees are all demanded in small and very perfect pieces to fill needs for which no others appear to be perfectly fitted. The holly (Ilex) grows in Europe and America, where the brilliant evergreen foliage and red berries have long been associated with the Christmas season. The name holly is probably a subversion of "Holy."[57] The true boxwood (Buxus sempervirens) attains to some size in Europe and Asia, but remains a small shrub in America, where it is seldom if ever cut for wood, but is placed as a decoration along the borders of walks and gardens. The wood called "boxwood" in America is not therefore derived from the "box." The Lignumvitæs grow in Florida, the West Indies, and on the northern coast of South America.

Holly-wood is noted for its fine, even grain, but chiefly for its smooth, ivory-white color, fitting it for the white of inlaid work, for carvings and other decorations where white color and fine qualities are required. The principal European source is the Ilex aquifolium, while in America it is the Ilex opaca. Boxwood is, as stated, the name applied to several woods, all noted for their fine compact structure, rendering them suitable for very fine carvings such as are required in wood-engraving. The Eastern product as cut from the true box is so highly prized as to be sold by the pound. American boxwood is chiefly derived from the Flowering Dogwood, the Mexican Persimmon, and the Rose Bay. In Australia several species of Eucalyptus are said to be used. Lignumvitæ is noted for great strength and hardness. Layers of fibres alternately cross one another so that the wood may be said to crumble rather than split. It has no superior for implements that must be [p104] fine, true, and strong, such as the sheaves of pulleys and handles of tools. The supply is obtained from two species (Guajacum sanctum and Guajacum officinale).

Holly may be known by its foliage and berries. Box (Buxus) has small, smooth, ovate, dark, evergreen leaves joining the stem so as to be opposite one another. The Dogwood is known by its flowers; the Lignum-vitæ is a low gnarled tree. [p105]

Holly, American Holly. Ilex opaca Ait.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

Dogwood, Flowering Dogwood. Cornus florida Linn.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

Lignumvitæ. Guajacum sanctum.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

LAUREL. (Magnolia, Rhododendron, Arbutus, etc.)

The name Laurel applies locally or botanically to a number of American plants, several of which attain to the dignity of trees.

The Big Laurel or Magnolia (M. grandiflora) is an ornamental tree of the highest rank, extensively planted in parks and gardens of American cities as far north as Washington, and also grown in Europe. The wood is suitable for interior finish and is also used for fuel. The California Laurel (Umbellularia californica) and the Madroña or Madroña Laurel (Arbutus menziesii) are Pacific coast species of beautiful appearance, the strong, heavy, hard woods of which are of economic importance. Professor Sargent considers[58] that the former is the most valuable interior or cabinet wood produced by the forests of the Pacific coast. The wood of the Madroña has little or no place in construction, but its charcoal is used in the manufacture of gunpowder. The wood of the Great Laurel or Rose Bay (Rhododendron maximum) has been used as boxwood. The gnarled roots of the Mountain Laurel or calico bush (Kalmia latifolia) are used for rustic hanging-baskets, seats, and the like.

All of the kinds here noted have evergreen foliage. [p109]

California Laurel, Mountain Laurel. Umbellularia californica Nutt.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

Madroña, Madroña Laurel. Arbutus menziesii Pursh.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

PLATE 23. PERSIMMON, OSAGE ORANGE, CHERRY (Diospyros), (Maclura), (Prunus).

Osage Orange Trunk (M. aurantiaca).	Wild Black Cherry Trunk (P. scrotina).
Cherry Wood.
Osage Orange Wood.
Persimmon Wood.

PERSIMMON (Diospyros.). OSAGE ORANGE (Maclura.). CHERRY (Prunus.).

The Persimmon (Diospyros virginiana) grows in many of the central and southern United States and affords a hard, tough wood, resembling fine-grain hickory, that is used for implements and other small work. The plum-like fruit is remarkably astringent when green, but is sweet, rich, and palatable when ripe. The persimmon is a member of the ebony family (Ebenaceæ), and the extremely close-grained heartwood is almost black. The ebony of commerce is derived from tropical species of this genus.

The Osage Orange or Bois D'Arc (Maclura aurantiaca) is found in the Gulf and neighboring States, and has been cultivated in the North. The wood is unusually hard and strong, and is of a yellow color, which, however, darkens with age. It is in many ways a unique and serviceable product, widely utilized locally in the South, but almost unknown in the North, and nowhere sufficiently appreciated. The aborigines made bows and arrows of it, whence the name Bois D'Arc. The tree affords a useless fruit somewhat resembling the common orange in appearance.

The widely distributed Wild Cherry or Wild Black Cherry (Prunus serotina) supplies the cherry wood of commerce. This wood is strong, hard, fine-grained, red-colored, and one of the most popular decorative woods of the American forests. Sweet or Cherry Birch (Betula lenta) is often stained so as to imitate it, while it of itself is stained so as to resemble mahogany. The wood of the cultivated cherry is not used in the United States. The wild cherry bears purplish-black fruit somewhat larger than peas, sweetly bitter when ripe. The bark is also bitter. It should be noted of these woods that the thin heart of the persimmon is black, that of the Bois d'Arc is yellow, and that of the cherry is red. Each receives a high polish. [p112]

Persimmon. Diospyros virginiana Linn.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

Osage Orange. Maclura aurantiaca Nutt. Toxylon pomiferum Raf.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Osage Orange.

Modulus of Rupture.

Remarks.

Wild Black Cherry, Wild Cherry. Prunus serotina Ehrh.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Wild Black Cherry (Prunus serotina).

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

PLATE 24. TEAK AND GREENHEART (Tectona, Nectandra, etc.).

Greenheart (Nectandra rodiali).	Teak Tree.
Teak (Tectona grandis).
Teakwood.
Lignumvitæ Wood.

TEAK (Tectona.). GREENHEART (Nectandra.).

There are two Teaks; the principal one (Tectona grandis), a native of Asia, has been called the "Oak" of the Indian forests, the other (Oldfieldia africana) is an African tree.[60] The Greenheart (Nectandra rodiali) is of the laurel family and grows in South America. The woods, although foreign, are of such nature as to have widely established reputations, and each has at some time been used in construction.

Teak suggests oak, save that it is lighter and has a more uniform structure. It is very durable, and an oily secretion repels insects and preserves iron fastenings. During the supremacy of wooden vessels it was regarded as one of the best ship-building woods in existence. The grain fits it for carvings, and it is now known in North America chiefly because of this fact. Indian teak is the wood usually referred to.

Greenheart was early placed among the first class of ship-building woods by Lloyd's Register, and is yet taken to Europe to some extent for dock-and ship-building and for implements, but is seldom found and but little known in the United States. It is strong, hard, durable, and extremely heavy, the latter quality being so pronounced as to limit its field of usefulness. [p116]

Teak. Tectona grandis.

Nomenclature.

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

Greenheart. Nectandra rodiali.

Nomenclature.

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

MAHOGANY. (Swietenia, Khaya, Soymida, Cedrela, etc.)

There are three principal mahogany trees: the Central American or true mahogany (Swietenia mahogani), the African mahogany (Khaya senegalensis), and the Indian mahogany (Soymida febrifuga). There are also minor species called mahoganies.[61] American mahogany was originally divided by dealers into Spanish and Honduras wood, the former from the then Spanish-American possessions. A considerable supply now comes from Mexico, taking name from port of shipment; as, Frontera, Laguna, Santa Ana, Tecolutla, Minatitlan, and Tonala, desirability being much in the order named. The African field is the latest and probably most important, very large quantities of its wood being distributed through English markets.

PLATE 25. MAHOGANY (Swietenia mahagoni).

Two Specimens of Wood.

Mahogany, placed among the second class of ship-building woods by Lloyd's Register, was once used to some extent in place of oak in naval architecture, but is now so greatly valued for decoration as to be employed for little else, save occasionally the hulls of small pleasure craft. The decorative value is due to a combination of beauty, working qualities, and durability. Beauty is influenced by both grain and warm red color. The latter is generally light, and although it subsequently darkens, in most cases, to a characteristic and rich reddish-brown, is usually induced immediately by stains. The grain is not only beautiful of itself, but is such as to receive those stains and finishing processes thus demanded. Different localities produce woods varying in tint and grain. Individual [p119] trees also differ in desirability. No two are alike. Beautiful grain effects are often obtained in "crotches" or junctions between trunk and branch, and such pieces bring high prices. Mahogany is generally used as a veneer. Layers are glued either to some central piece or "core" or else to one another. The layers are arranged so as to cross one another's grain, and results are usually thought to be more desirable than those obtained from solid wood. Few woods glue better, and few shrink or distort less when in place.

"Spanish Cedar" (Cedrela odorata) is a broadleaf wood, and not a conifer as is usually supposed. It is nearly related to, and usually found and cut with, true mahogany. Lindley[62] divides Cedrelecæ into two sub-orders: Swieteniæ, including the true mahoganies, and Cedrelæ, with nine genera and twenty-five species distributed over tropical Asia and America.

Prima vera or white mahogany belongs to Bignoniaceæ, which also includes the catalpas. [p120]

Mahogany. Swietenia mahogani Jacq.

Nomenclature.

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

White Mahogany. Prima vera. Tabeuia Donnell-Smithii (Rose).

Nomenclature.

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

Spanish Cedar, Mexican Cedar. Cedrela odorata Linn.

Nomenclature.

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

PLATE 26. EUCALYPTUS (Eucalyptus).

Blue Gum Tree (E. globulus) California.	Blue Gum Bark (E. globulus) California.
	Jarrah Trunk, (E. marginata) Australia.
Jarrah Wood (E. marginata).
Karri Wood (E. diversicolor).

EUCALYPTUS. (Eucalyptus.)

These trees, locally known as Stringy-barks, Iron-barks, and Gum-trees, are natives of Australia and the neighboring islands. Some of the nearly four hundred species have been widely transplanted, although none have thus far succeeded in this country outside of Florida and California.[63] The Blue Gum (E. globulus) is the species commonly referred to when Eucalyptus is mentioned in North America.

The Eucalypts are noted for their great size, rapid growth, tough, durable wood, and alleged effect upon health. Size is illustrated by the species Eucalyptus amygdalina, specimens of which have reached a height of four hundred and eighty feet and are thus the tallest, although not the largest, trees known to man. Growth is shown by specimens of the Eucalyptus gunnii, which have grown in excess of two feet a month during the first year.[64] The working qualities of Jarrah, Karri, and Tuart woods (E. marginata, E. diversicolor, and E. gomphocephala) are such as to cause them to take high rank in local construction. The first two have been preferred beyond all other species for paving the streets of London and of Paris. Some improvement in health is said to have followed the introduction of the Blue Gum (Eucalyptus globulus) in malarial districts, such as those around Rome. It is not certain whether these results are due to the presence of essences in the foliage, although medicinal properties are ascribed to them and they are used in the preparation of listerine and similar compounds, or [p124] whether they are due to the fact that the leaves evaporate unusual quantities of water drawn by the roots from the soil.[65]

The trees are characterized by leathery evergreen foliage of many shades, such as blue, gray, and green. The leaves of young and old trees differ widely in some species. Those of young blue gums are bright blue, oval, and stalkless, while leaves of older trees have stems, are dark green and sickle-shaped. The characteristic odor is the only point in common between the foliage of the old and young of this species. There are, as stated, nearly four hundred species. [p125]

Jarrah. Eucalyptus marginata.

Nomenclature.

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

Karri. Eucalyptus diversicolor.

Nomenclature.

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

Tuart. Eucalyptus gomphocephala.

Nomenclature.

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

Blue Gum, Fever Tree. Eucalyptus globulus.

Nomenclature.

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

PLATE 27. PINE (Pinus).

White Pine Foliage (P. strobus).	Hard Pine Trunk (P. palustris). (Photograph by Edward J. Davison.)
White Pine Tree (P. strobus). (Courtesy N. C. Geol. Survey.)
Hard Pine Wood (P. palustris).
Soft or Sugar Pine Wood (P. lambertiana).

NEEDLELEAF WOODS.

The trees affording these woods cover large areas in the natural forests of the Northern Hemisphere. They exist, but to an unimportant extent, in the South. Cedar, larch, and cypress figure in ancient history, but woods generally were not employed until recent times.[71] Pine, spruce, hemlock, and other so-called soft woods are of this group.

Needle-leaved woods are characterized by uniform fibre-conditions, presence of resins, and lighter weights. The vertical structure consists of simple, similar, elongated tubes or cells, tapering and finally closing at their ends, known as tracheids. These are arranged with more or less regularity, and woods are correspondingly easy to work. Pith-rays are scarcely visible, and sections do not show pores. Cavities known as resin-ducts, and which are not real vessels but rather simple intercellular spaces, secrete resins so important in making these woods durable and elastic. Trees afford large, straight pieces. Woods are used in carpentry and heavy constructions. The total requirement greatly exceeds that for hard woods.

The resinous, usually evergreen, leaves and the cones are sufficient to identify these trees. Needleleaf, softwood, conifer, and evergreen trees are the same. [p130]

PINE. (Pinus.)

These trees were not regarded seriously until about the latter half of the eighteenth century. Their woods are now the principal ones in carpentry and construction, and are more used than any others. They are to the soft woods what the oaks are to the hard woods, and they stand at present with reference to all woods much as iron does to all metals. Pine is prized because of a combination of strength, elasticity, light weight, working qualities, and availability, such as fits it for those constructions requiring the largest quantities of wood.

The pines have smooth, straight, solid trunks, usually destitute of branches for many feet from the ground. There are needle-shaped, more or less cylindrical, evergreen leaves from one to many inches in length, gathered in clusters of two, three, or five, their number and the fact that they are thus clustered being important bases of classification. There are also cones of woody overlapping scales. They reproduce with difficulty,[72] and mature so slowly that ultimate survival of modern conditions must probably be as cultivated trees.

Thirty-nine of the seventy known species of pine are found in the United States. These with their woods are separated into two groups known as hard and soft pines. The Dantzic or Northern pine (Pinus silvestris) is the principal European species. [p131]

SOFT PINE.

Soft pine is soft, clean, light, uniform, easily worked, not strong, free from knots and resins, and obtainable in large and perfect pieces. The wood is whitish and the yearly rings are not pronounced. The supply is divided, as obtained from the white pine on the one hand, and from the sugar-pine and all other species on the other.

White pine (Pinus strobus) grows in the north, central, and eastern United States and was formerly the important tree of North America. It emphasized the forest industries of Maine and of Michigan, and methods connected with harvesting it have influenced logging practices in many fields. It was long the only softwood seriously considered by Northern lumbermen. Thirty per cent of the sawn timber and lumber used in this country in 1899 was drawn from this species.[73] White pine is diminishing so rapidly as to be already practically unobtainable in many places.

The Sugar Pine (Pinus lambertiana) of the Western States is a tree growing at high elevations and is so large as to take rank with the redwoods and other of the world's greatest trees. Some material is derived from the Western white pine (Pinus flexilis) and one or more minor species. Sugar pine resembles, but is not as desirable as, white pine. The sweetish exudations from this tree are sometimes used in medicine. [p132]

HARD PINE.

Hard pine differs from soft pine in that it is hard, resinous, heavy, harder to work, and very strong. It also is obtainable in large pieces. The orange-yellow wood is more or less figured. The annual deposits are pronounced and are separated into two sharply divided rings. The supply is chiefly derived from the longleaf, shortleaf, Cuban, and loblolly pines of the South Atlantic States.

The longleaf pine (Pinus palustris) is distinctly the most important of its group. The wood is ideal for heavy constructions. Beams, docks, trestles, and frames of cars are formed of it. The trees afford the greater bulk of turpentine, tar, and resin, or "naval stores," produced in this country.[74] Cuban, shortleaf, and loblolly pine woods (P. heterophylla, P. echinata, and P. tæda) are nearly similar. Longleaf and Cuban pines are seldom separated, while shortleaf and loblolly pines are also mixed. Longleaf pine usually affords finer structure and more heartwood than Cuban pine. Strength and weight averages of both woods are in excess of those of shortleaf and loblolly pines. No method of invariably telling these four woods apart has as yet been determined. (Roth.) Any or all of them are practically liable to be delivered in response to a demand for Southern pine. Johnson considers shortleaf pine as good as longleaf pine of equal weight, and suggests environment as a means of identification.

Palustris, signifying "swampy," is misleading, since long leaf pine prefers dry, sandy soil and tracts known as "pine barrens." Mitis refers to the soft, delicate foliage of shortleaf pine. Tæda signifies "torch." The trees may be told by differences in their leaves and cones. [p133]

A confusion exists in the naming of the pines. American white pine is known as yellow or Weymouth pine in Europe, and all American hard pines are there often known as pitch pines. The European, Dantzic, or Northern pine has also many names, principally depending on port of shipment. Georgia, Southern, Yellow, Hard, and even Pitch pine, are interchangeable names in this country. The species palustris has thirty local names. [p134]

White Pine. Pinus strobus Linn.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

White Pine. Pinus flexilis James.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

Sugar Pine. Pinus lambertiana Dougl.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

White Pine. Pinus monticola Dougl.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

Georgia Pine, Hard Pine, Yellow Pine, Longleaf Pine. Pinus palustris Mill.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

Cuban Pine. Pinus heterophylla Sudw.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

Shortleaf Pine, Yellow Pine. Pinus echinata Mill. Pinus mitis Michx.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

Loblolly Pine. Pinus tæda Linn.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

Bull Pine, Yellow Pine, Western Yellow Pine. Pinus ponderosa Laws.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

Norway Pine, Red Pine. Pinus resinosa Ait.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

Pitch Pine. Pinus rigida Mill.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

Northern Pine, Scotch Pine, Dantzic Pine. Pinus sylvestris Linn.

Nomenclature.

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

KAURI PINE. (Dammara.)

This New Zealand tree affords one of the best substitutes for northern pine. Although not true pine, it belongs to the same family as the pine and other conifers. The light, strong, durable, elastic wood is obtainable in large-sized pieces suitable for masts.

The species is universally noted for its resin, which possesses the quality of uniting more perfectly than others with linseed oil.[82] Kauri gum is thus one of the most valuable constituents of good varnish.[83] The best gum occurs as a fossil, and is collected by digging over areas known to be fruitful but from which trees have long since disappeared. The pieces, varying in size from small pebbles to lumps as large as eggs, are scraped and otherwise cleansed by natives in the fields.[84] [p147]

PLATE 28. KAURI PINE (Dammara australis).

Top--From R. Ingham Clark, by courtesy of Messrs. Pratt & Lambert.

Bottom--Fragments of Gum one-quarter natural size. "Fossil gum" at right and centre.

Kauri Pine. Dammara australis.

Nomenclature.

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

SPRUCE. (Picea.)

The spruces form forests in Europe and North America. The black spruce (P. nigra) and the white spruce (P. alba) predominate in eastern United States, while the white spruce (P. engelmanni) is important in the West. The Norway spruce, or white fir (P. excelsa), is the chief European species. American trees prefer Northern ranges characterized by short summers and long winters.

The soft, light, clean woods resemble and are probably the best substitute for soft pine. They are apt to warp and twist in seasoning and so are not good for posts and trusses. Spruce is the principal wood in New England for studding and floor-joists. The product is divided commercially and according to appearance, but irrespective of species, into white and black spruce. These terms depend sometimes, at least, on the wide and narrow rings of the black spruce (P. nigra). It should be remembered that spruce and fir woods are often confused with one another, and that there are trees, as the Douglas spruce and Kauri pine or spruce, that are called, but are not, true spruces. European spruce is often locally known as white deal.

Spruce trees have single, sharp-pointed, short leaves, pointing everywhere, and keeled above and below so as to appear four-sided; the cones hang down. Spruce may be distinguished from the pines, firs, and hemlocks by the fact that pine leaves are longer and in clusters, that hemlock leaves are flat, blunt, and two-ranked, and that fir cones point upward. The genus picea has twelve species, five of which are North American. The resins of the black and red spruce are used as confections. [p149]

PLATE 29. BLACK SPRUCE (Picea nigra).

The following table sets forth the primary distinctions between the spruces and the pines, firs, and hemlocks:

[p150]

Black Spruce. Picea nigra Link. Picea mariana Mill.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

White Spruce. Picea alba Link. Picea canadensis Mill.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

White Spruce. Picea engelmanni Engelm.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

Sitka Spruce. Picea sitchensis Trautv. and Mayer.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

DOUGLAS SPRUCE. (Pseudotsuga.)

The Douglas or Red Pine, Spruce, or Fir, of the Pacific coast is neither true pine, spruce, nor fir, but a sort of bastard hemlock. The name "pseudotsuga" is from pseudo, or false, and tsuga, or hemlock. The trees are among the greatest known. The wood resembles larch or hard pine in properties, appearance, and applications. Trees have been successfully planted in the Adirondacks. The species was earlier classed as Pinus taxifolia and as Abies taxifolia. [p155]

PLATE 30. DOUGLAS SPRUCE (Pseudotsuga taxifolia).

Douglas Spruce, Douglas Fir. Pseudotsuga taxifolia Lam. Pseudotsuga Douglasii Carr.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

FIR. (Abies.)

Several of the fir-trees of the western United States attain to very great size. The silver fir (Abies grandis) and the white fir (Abies concolor) supply much wood in the section in which they grow. The balsam fir (Abies balsamea) of the Eastern States is of some commercial importance.

Balsam Fir (Abies balsamea).

Fir wood resembles spruce in appearance and in structural qualities. It may be told from spruce as well as from pine and larch by the fact that fir has no resin-ducts. The balsam fir is distinguishable by clear liquid resin which appears in blisters in the bark. The coarse, weak wood is cleaner than the bark would indicate. Spruce and fir woods are often confused in the United States, while pine, spruce, and fir are similarly confounded in Europe.

Fir trees have flat, scattered, evergreen leaves, and cones that stand erect (see footnote under spruce). [p157]

Balsam Fir, Common Balsam Fir. Abies balsamea Mill.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

Great Silver Fir, White Fir. Abies grandis Lindl.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

White Fir, Balsam Fir. Abies concolor Parry.

Nomenclature. (Sudworth).

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

Red Fir. Abies magnifica Murr.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

Red Fir, Noble Fir. Abies nobilis Lindl.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

HEMLOCK. (Tsuga.)

The hemlocks are distributed over northern United States from Maine to Michigan, in the Rocky Mountains, and on the Pacific coast. They generally mingle with broad-leaved and other needle-leaved species, but occasionally form pure forests by themselves.

The wood is coarse, often crossed-grained, perishable, brittle, liable to wind-shakes, hard to work, and apt to warp and splinter. It holds nails firmly and is used for coarse lumber, dimension pieces, paper-pulp, and latterly for cheap finish. It should not be relied upon to receive shocks. The bark is used in tanning.

Hemlock trees may be known by their blunt, flat, evergreen leaves, appearing two-ranked and whitened beneath (see foot-note under Spruce). Red inner bark. [p163]

PLATE 31. HEMLOCK (Tsuga).

Hemlock Tree (Tsuga canadensis).	Western Hemlock Tree (T. heterophylla). (6500 feet above sea-level.)
Hemlock Foliage (Tsuga canadensis).
Hemlock Wood (Tsuga canadensis).

Hemlock. Tsuga canadensis.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

LARCH. TAMARACK. (Larix.)

Larch was well known in the older time, and was prized in Europe and the Orient. The two principal American species are also called tamarack and hackmatack. The Eastern larch or tamarack (L. americana) prefers peculiar low, wet areas known as tamarack swamps. The Western tree (L. occidentalis) resembles the European species and prefers dry places.

Larch wood has always been regarded as very durable. It is noted by Pliny and other ancient authors.[88] Vitruvius mentions a bridge that, having burned, was replaced by one of larch, because that wood would not burn as readily.[89] The foundation-piles of Venice are said to be of larch.[90] It should be remembered that the identities of ancient woods are not always beyond question. American larch resembles, if it does not equal, true foreign wood. The trees are tall and straight, but so slender as to be seldom cut into lumber, almost the entire supply being demanded for posts, ties, and poles. The exceedingly durable wood resembles spruce in structure, and hard pine in weight and appearance.

Larch trees are marked by the fact that their foliage is deciduous. The little leaves, gathered in tufts or bundles, are of a bright pea-green when fresh in the springtime. The appearance of tamarack trees when divested of foliage in the winter is very gloomy. [p165]

PLATE 32. LARCH (Larix).

Larch Trees in Winter.

Tamarack, Larch. Larix americana Michx. Larix laricina (Du Roi) Koch.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

Tamarack Larch. Larix occidentalis.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

PLATE 33. CEDAR (Cedrus, Thuya, etc.).

Cedar of Lebanon (Cedrus libani).	Foliage of White Cedar (T. occidentalis).
Red Cedar Bark (Juniperus virginiana).	Foliage of Red Cedar (J. virginiana).
White Cedar Wood (Thuya occidentalis).	Tree of Red Cedar (J. virginiana).

CEDAR. (Cedrus, Thuya, Chamæcyparis, Libocedrus, Juniperus.)

Cedar was a name first applied to the true or Lebanon cedars (Cedrus) of the Eastern continent, but later to certain Arborvitæs (Thuya), Junipers (Juniperus), and Cypresses (Chamæcyparis), and other trees (see "Spanish Cedar," page 122) from which durable, fine-grained, more or less fragrant woods, known as cedar, are obtained. Cedar was highly prized by the ancients, who employed it in costly constructions, such as the temples of Solomon and of Diana at Ephesus.[91] [92] Woods known as cedar are divided into so-called Red and White Cedars.

Red Cedar is very fine-grained, soft, light, durable, fragrant, and of a pinkish-red color. Much wood is derived from the Red Cedars, Juniperus virginiana, Juniperus scopulorum, and Juniperus barbadensis, of the Eastern, Western, and Southern States respectively. Although seen in construction, red cedar is chiefly used in chests, closets, lead-pencils, and cigar-boxes. One hundred and twenty-five thousand trees (125,000)[93] are annually required for lead-pencils alone. The waste is often converted into shavings and used instead of camphor to protect woolens. The demand is greater than the supply. Trees are easily grown on almost any soil. Trees and wood are subject to fungus diseases which apparently cease after trees have been felled; the wood is then durable.[94]

White Cedar is best defined as all cedar that is not "red cedar," [p168] and is obtained from several valuable trees.[95] The arborvitæs (T. occidentalis) vary in size from large bushes used in hedging and ornamentation to small-sized trees gathered for wood. They are most vigorous on cold, wet areas known as cedar swamps.[96] The giant arborvitæ (T. gigantea), noted for its great girth, and the yellow and Lawson Cypresses, are important Pacific coast species. The incense cedar, while much subject to fungus trouble, is also prized.[97] White cedar wood is durable, plentiful, and employed in exposed positions as ties and shingles.

Arborvitæs (Thuya) have very small overlapping leaves that form flat rods or fan-like sprays. The cones are oblong, less than one-half inch in length, and all of their six or eight scales separate or open when ripe. The cypresses (Chamæcyparis) exhibit similar foliage, but their tiny cones are simple, roughened, close, or solid globules. The Junipers (Juniperus) often, but not always, bear bluish-black berries powdered with a whitish-blue bloom. The true cedars (Cedrus) differ from the others in that they have simple needle leaves, an inch, more or less, in length, together with cones erect and several inches in length. The Deodar or cedar of India is of this genus. The principal American red and white cedars are as follows:

[p169]

Red Cedar. Juniperus virginiana Linn.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

Juniper. Juniperus occidentalis Hook.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

White Cedar, Arborvitæ. Thuya occidentalis Linn.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

Canoe Cedar, Arborvitæ. Giant Arborvitæ. Thuya plicata Don. Thuya gigantea Nutt.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

White Cedar. Chamæcyparis thyoides L.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.

Modulus of Rupture.

Remarks.

Port Orford Cedar, Lawson Cypress. Chamæcyparis lawsoniana Murr.

Nomenclature. (Sudworth.)

Locality.

Features of Tree.

Color, Appearance, or Grain of Wood.

Structural Qualities of Wood.

Representative Uses of Wood.

Weight of Seasoned Wood in Pounds per Cubic Foot.

Modulus of Elasticity.