[PRINCIPAL TREE REGIONS OF NORTH AMERICA]

A North Eastern B North Western AB North Eastern & North Western C South Eastern D Tropical Florida E Texas-Mexican Boundary F Rocky Mountains G Oregon & California H New Mexico & Arizona Mexican Boundary

MANUAL OF THE TREES OF NORTH AMERICA
(EXCLUSIVE OF MEXICO)

BY
CHARLES SPRAGUE SARGENT
Director of the Arnold Arboretum of Harvard University
Author of The Silva of North America

WITH SEVEN HUNDRED AND EIGHTY-THREE ILLUSTRATIONS FROM DRAWINGS BY
CHARLES EDWARD FAXON
AND
MARY W. GILL

Second Edition

BOSTON AND NEW YORK
HOUGHTON MIFFLIN COMPANY
The Riverside Press Cambridge
1922

TO
M. R. S.
THE WISE AND KIND FRIEND OF THIRTY YEARS
THIS BOOK IS DEDICATED
WITH GRATITUDE AND AFFECTION

PREFACE TO THE SECOND EDITION

The studies of the trees of North America (exclusive of Mexico) which have been carried on by the agents and correspondents of the Arboretum in the sixteen years since the publication of the Manual of the Trees of North America have increased the knowledge of the subject and made necessary a new edition of this Manual. The explorations of these sixteen years have added eighty-nine species of trees and many recently distinguished varieties of formerly imperfectly understood species to the silva of the United States, and made available much additional information in regard to the geographical distribution of American trees. Further studies have made the reduction of seven species of the first edition to varieties of other species seem desirable; and two species, Amelanchier obovalis and Cercocarpus parvifolius, which were formerly considered trees, but are more properly shrubs, are omitted. The genus Anamomis is now united with Eugenia; and the Arizona Pinus strobiformis Sarg. (not Engelm.) is now referred to Pinus flexilis James.

Representatives of four Families and sixteen Genera which did not appear in the first edition are described in the new edition in which will be found an account of seven hundred and seventeen species of trees in one hundred and eighty-five genera, illustrated by seven hundred and eighty-three figures, or one hundred and forty-one figures in addition to those which appeared in the first edition.

An International Congress of Botanists which assembled in Vienna in 1905, and again in Brussels in 1910, adopted rules of nomenclature which the world, with a few American exceptions, has now generally adopted. The names used in this new Manual are based on the rules of this International Congress. These are the names used by the largest number of the students of plants, and it is unfortunate that the confusion in the names of American trees must continue as long as the Department of Agriculture, including the Forest Service of the United States, uses another and now generally unrecognized system.

The new illustrations in this edition are partly from drawings made by Charles Edward Faxon, who died before his work was finished; it was continued by the skillful pencil of Mary W. Gill, of Washington, to whom I am grateful for her intelligent coöperation.

It is impossible to name here all the men and women who have in the last sixteen years contributed to this account of American trees, and I will now only mention Mr. T. G. Harbison and Mr. E. J. Palmer, who as agents of the Arboretum have studied for years the trees of the Southeastern States and of the Missouri-Texas region, Professor R. S. Cocks, of Tulane University, who has explored carefully and critically the forests of Louisiana, and Miss Alice Eastwood, head of the Botanical Department of the California Academy of Sciences, who has made special journeys in Alaska and New Mexico in the interest of this Manual. Mr. Alfred Rehder, Curator of the Herbarium of the Arboretum, has added to the knowledge of our trees in several Southern journeys; and to him I am specially indebted for assistance and advice in the preparation of the keys to the different groups of plants found in this volume.

This new edition of the Manual contains the results of forty-four years of my continuous study of the trees of North America carried on in every part of the United States and in many foreign countries. If these studies in any way serve to increase the knowledge and the love of trees I shall feel that these years have not been misspent.

C. S. Sargent. Arnold Arboretum
September, 1921

PREFACE

In this volume I have tried to bring into convenient form for the use of students the information concerning the trees of North America which has been gathered at the Arnold Arboretum during the last thirty years and has been largely elaborated in my Silva of North America.

The indigenous trees of no other region of equal extent are, perhaps, so well known as those that grow naturally in North America. There is, however, still much to be learned about them. In the southern states, one of the most remarkable extratropical regions in the world in the richness of its arborescent flora, several species are still imperfectly known, while it is not improbable that a few may have escaped entirely the notice of botanists; and in the northern states are several forms of Cratægus which, in the absence of sufficient information, it has been found impracticable to include in this volume. Little is known as yet of the silvicultural value and requirements of North American trees, or of the diseases that affect them; and one of the objects of this volume is to stimulate further investigation of their characters and needs.

The arrangement of families and genera adopted in this volume is that of Engler & Prantl’s Die Natürlichen Pflanzenfamilien, in which the procession is from a simpler to a more complex structure. The nomenclature is that of The Silva of North America. Descriptions of a few species of Cratægus are now first published, and investigations made since the publication of the last volume of The Silva of North America, in December, 1902, have necessitated the introduction of a few additional trees described by other authors, and occasional changes of names.

An analytical key to the families, based on the arrangement and character of the leaves, will lead the reader first to the family to which any tree belongs; a conspectus of the genera, embodying the important and easily discovered contrasting characters of each genus and following the description of each family represented by more than one genus, will lead him to the genus he is trying to determine; and a similar conspectus of the species, following the description of the genus, will finally bring him to the species for which he is looking. Further to facilitate the determination, one or more letters, attached to the name of the species in the conspectus following the description of the genus, indicate in which of the eight regions into which the country is divided according to the prevailing character of the arborescent vegetation that species grows (see [map] forming frontispiece of the volume). For example, the northeastern part of the country, including the high Appalachian Mountains in the southern states which have chiefly a northern flora, is represented by (A), and a person wishing to learn the name of a Pine-tree or of an Oak in that region need occupy himself only with those species which in the conspectus of the genus Quercus or Pinus are followed by the letter (A), while a person wishing to determine an Oak or a Pine-tree in Oregon or California may pass over all species which are not followed by (G), the letter which represents the Pacific coast region south of the state of Washington.

The sign of degrees (°) is used in this work to represent feet, and the sign of minutes (′) inches.

The illustrations which accompany each species and important variety are one half the size of nature, except in the case of a few of the large Pine cones, the flowers of some of the Magnolias, and the leaves and flower-clusters of the Palms. These are represented as less than half the size of nature in order to make the illustrations of uniform size. These illustrations are from drawings by Mr. Faxon, in which he has shown his usual skill and experience as a botanical draftsman in bringing out the most important characters of each species, and in them will be found the chief value of this Manual. For aid in its preparation I am indebted to him and to my other associates, Mr. Alfred Rehder and Mr. George R. Shaw, who have helped me in compiling the most difficult of the keys.

C. S. Sargent. Arnold Arboretum, Jamaica Plain, Mass.
January, 1905.

[Map of North America (exclusive of Mexico) showing the eight regions into which the country is divided according to the prevailing character of the trees] Frontispiece [Synopsis of the Families of Plants described in this work] xi [Analytical Key to the Genera of Plants described in this work, based chiefly on the character of their leaves] xvi [Manual of Trees] 1 [Gymnospermæ] 1 [Angiospermæ] 96 [Monocotyledons] 96 [Dicotyledons] 118 [Apetalæ] 118 [Petalatæ] 342 [Polypetalæ] 342 [Gamopetalæ] 790 [Glossary of Technical Terms] 893 [Index] 899

SYNOPSIS
OF THE FAMILIES OF PLANTS DESCRIBED IN THIS BOOK

Class I. GYMNOSPERMÆ.

Resinous trees; stems formed of bark, wood, or pith, and increasing in diameter by the annual addition of a layer of wood inside the bark; flowers unisexual; stamens numerous; ovules and seeds 2 or many, borne on the face of a scale, not inclosed in an ovary; embryo with 2 or more cotyledons; leaves straight-veined, without stipules.

I. Pinaceæ ([p. 1]). Flowers usually monœcious; ovules 2 or several; fruit a woody cone (in Juniperus berry-like); cotyledons 2 or many; leaves needle-shaped, linear or scale-like, persistent (deciduous in Larix and Taxodium). II. Taxaceæ ([p. 90]). Flowers diœcious, axillary, solitary; ovules 1; fruit surrounded by or inclosed in the enlarged fleshy aril-like disk of the flower; cotyledons 2; leaves linear, alternate, persistent.

Class II. ANGIOSPERMÆ.

Carpels or pistils consisting of a closed cavity containing the ovules and becoming the fruit.

Division I. MONOCOTYLEDONS.

Stems with woody fibres distributed irregularly through them, but without pith or annual layers of growth; parts of the flower in 3’s; ovary superior, 3-celled; embryo with a single cotyledon; leaves parallel-veined, persistent, without stipules.

III. Palmæ ([p. 96]). Ovule solitary; fruit baccate or drupaceous, 1 or rarely 2 or 3-seeded; leaves alternate, pinnate, flabellate or orbicular, persistent. IV. Liliaceæ ([p. 110]). Ovules numerous in each cell; fruit 3-celled, capsular or baccate; leaves linear-lanceolate.

Division II. DICOTYLEDONS.

Stems formed of bark, wood, or pith, and increasing by the addition of an annual layer of wood inside the bark; parts of the flower mostly in 4’s or 5’s; embryo with a pair of opposite cotyledons; leaves netted-veined.

Subdivision 1. Apetalæ. Flowers without a corolla and sometimes without a calyx.

Section 1. Flowers in unisexual aments (female flowers of Juglans and Quercus solitary or in spikes); ovary inferior (superior in Leitneriaceæ) when a calyx is present.

V. Salicaceæ ([p. 119]). Flowers diœcious, without a calyx. Fruit a 2—4-valved capsule. Leaves simple, alternate, with stipules, deciduous. VI. Myricaceæ ([p. 163]). Flowers monœcious or diœcious; fruit a dry drupe, covered with waxy exudations; leaves simple, alternate, resinous-punctate, persistent. VII. Leitneriaceæ ([p. 167]). Flowers diœcious, the staminate without a calyx; ovary superior; fruit a compressed oblong drupe; leaves alternate, simple, without stipules, deciduous. VIII. Juglandaceæ ([p. 168]). Flowers monœcious; fruit a nut inclosed in an indehiscent (Juglans) or 4-valved (Carya) fleshy or woody shell; leaves alternate, unequally pinnate without stipules, deciduous. IX. Betulaceæ ([p. 200]). Flowers monœcious; fruit a nut at the base of an open leaf-like involucre (Carpinus), in a sack-like involucre (Ostrya), in the axil of a scale of an ament (Betula), or of a woody strobile (Alnus); leaves alternate, simple, with stipules, deciduous. X. Fagaceæ ([p. 227]). Flowers monœcious; fruit a nut more or less inclosed in a woody often spiny involucre; leaves alternate, simple, with stipules, deciduous (in some species of Quercus and in Castanopsis and Lithocarpus persistent).

Section 2. Flowers unisexual (perfect in Ulmus); calyx regular, the stamens as many as its lobes and opposite them; ovary superior, 1-celled; seed 1.

XI. Ulmaceæ ([p. 308]). Fruit a compressed winged samara (Ulmus), a drupe (Celtis and Trema), or nut-like (Planera), leaves simple, alternate, with stipules, deciduous (persistent in Trema). XII. Moraceæ ([p. 328]). Flowers in ament-like spikes or heads; fruit drupaceous, inclosed in the thickened calyx and united into a compound fruit, oblong and succulent (Morus), large, dry and globose (Toxylon), or immersed in the fleshy receptacle of the flower (Ficus); leaves simple, alternate, with stipules, deciduous (persistent in Ficus).

Section 3. Flowers usually perfect; ovary superior or partly inferior, 1—4-celled; leaves simple, persistent in the North American species.

XIII. Olacaceæ ([p. 336]). Calyx and corolla 4—6-lobed; ovary 1—4-celled; fruit a drupe more or less inclosed in the enlarged disk of the flower; leaves alternate or fascicled, without stipules. XIV. Polygonaceæ ([p. 338]). Calyx 5-lobed; ovary 1-celled; fruit a nutlet inclosed in the thickened calyx; leaves alternate, their stipules sheathing the stems. XV. Nyctaginaceæ ([p. 340]). Calyx 5-lobed; ovary 1-celled; fruit a nutlet inclosed in the thickened calyx; leaves alternate or opposite, without stipules.

Subdivision 2. Petalatæ. Flowers with both calyx and corolla (without a corolla in Lauraceæ, in Liquidambar in Hamamelidaceæ, in Cercocarpus in Rosaceæ, in Euphorbiaceæ, in some species of Acer, in Reynosia, Condalia, and Krugiodendron in Rhamnaceæ, in Fremontia in Sterculiaceæ, in Chytraculia in Myrtaceæ, in Conocarpus in Combretaceæ and in some species of Fraxinus in Oleaceæ).

Section 1. Polypetalæ. Corolla of separate petals.

A. Ovary superior (partly inferior in Hamamelidaceæ; inferior in Malus, Sorbus, Heteromeles, Cratægus, and Amelanchier in Rosaceæ).

XVI. Magnoliaceæ ([p. 342]). Flowers perfect; sepals and petals in 3 or 4 rows of 3 each; fruit cone-like, composed of numerous cohering carpels; leaves simple, alternate, their stipules inclosing the leaf-buds, deciduous or rarely persistent. XVII. Anonaceæ ([p. 353]). Flowers perfect; sepals 3; petals 6 in 2 series; fruit a pulpy berry developed from 1 or from the union of several carpels; leaves simple, alternate, without stipules, deciduous or persistent. XVIII. Lauraceæ ([p. 356]). Flowers perfect or unisexual; corolla 0; fruit a 1-seeded drupe or berry; leaves simple, alternate, punctate, without stipules, persistent (deciduous in Sassafras). XIX. Capparidaceæ ([p. 365]). Flowers perfect; sepals and petals 4; fruit baccate, elongated, dehiscent; leaves alternate, simple, without stipules, persistent. XX. Hamamelidaceæ ([p. 366]). Flowers perfect or unisexual; sepals and petals 5 (corolla 0 in Liquidambar); ovary partly inferior; fruit a 2-celled woody capsule opening at the summit; leaves simple, alternate, with stipules, deciduous. XXI. Platanaceæ ([p. 371]). Flowers monœcious, in dense unisexual capitate heads; fruit an akene; leaves simple, alternate, with stipules, deciduous. XXII. Rosaceæ ([p. 376]). Flowers perfect; sepals and petals 5 (petals 0 in Cercocarpus); ovary inferior in Malus, Sorbus, Heteromeles, Cratægus, and Amelanchier; fruit a drupe (Prunus and Chrysobalanus), a capsule (Vauquelinia and Lyonothamnus), an akene (Cowania and Cercocarpus), or a pome (Malus, Sorbus, Heteromeles, Cratægus, and Amelanchier); leaves simple or pinnately compound, alternate (opposite in Lyonothamnus), with stipules, deciduous or persistent. XXIII. Leguminosæ ([p. 585]). Flowers perfect, regular or irregular; fruit a legume; leaves compound, or simple (Dalea), alternate, with stipules, deciduous or persistent. XXIV. Zygophyllaceæ ([p. 630]). Flowers perfect; calyx 5-lobed; petals 5; fruit capsular, becoming fleshy; leaves opposite, pinnate, with stipules, persistent. XXV. Malpigiaceæ ([p. 631]). Flowers usually perfect rarely dimorphous; calyx 5-lobed; petals 5, unguiculate; fruit a drupe or samara; leaves opposite, simple, entire, persistent; often with stipules. XXVI. Rutaceæ ([p. 633]). Flowers unisexual or perfect; fruit a capsule (Xanthoxylum), a samara (Ptelea), of indehiscent winged 1-seeded carpels (Helietta), or a drupe (Amyris); leaves alternate or opposite, compound, glandular-punctate, without stipules, persistent or rarely deciduous (0 in Canotia). XXVII. Simaroubaceæ ([p. 641]). Flowers diœcious, calyx 5-lobed; petals 5; fruit drupaceous (Simarouba), baccate (Picramnia), a samara (Alvaradoa); leaves alternate, equally pinnate, without stipules, persistent. XXVIII. Burseraceæ ([p. 645]). Flowers perfect; calyx 4 or 5-parted; petals 5; fruit a drupe; leaves alternate, compound, without stipules, deciduous. XXIX. Meliaceæ ([p. 648]). Flowers perfect; calyx 5-lobed; petals 5; fruit a 5-celled dehiscent capsule; leaves alternate, equally pinnate, without stipules, persistent. XXX. Euphorbiaceæ ([p. 649]). Flowers perfect; calyx 4—6-parted (Drypetes), 3-lobed (Hippomane), or 0 (Gymnanthes); petals 0; fruit a drupe (Drypetes and Hippomane), or a 3-lobed capsule (Gymnanthes). XXXI. Anacardiaceæ ([p. 655]). Flowers usually unisexual, diœcious or polygamo-diœcious (Pistacia without a calyx, and without a corolla in the North American species); fruit a dry drupe; leaves simple or compound, alternate, without stipules, deciduous (persistent in Pistacia and in one species of Rhus). XXXII. Cyrillaceæ ([p. 665]). Flowers perfect; calyx 5—8-lobed; petals 5—8; fruit an indehiscent capsule; leaves alternate, without stipules, persistent (more or less deciduous in Cyrilla). XXXIII. Aquifoliaceæ ([p. 668]). Flowers polygamo-diœcious; calyx 4 or 5-lobed; petals 5; fruit a drupe, with 4—8 1-seeded nutlets; leaves alternate, simple, with stipules, persistent or deciduous. XXXIV. Celastraceæ ([p. 674]). Flowers perfect, polygamous or diœcious; calyx 4 or 5-lobed; petals 4 or 5; fruit a drupe, or a capsule (Evonymus); leaves simple, opposite or alternate, with or without stipules, persistent (deciduous in Evonymus). XXXV. Aceraceæ ([p. 681]). Flowers diœcious or monœciously polygamous; calyx usually 5-parted; petals usually 5, or 0; fruit of 2 long-winged samara joined at the base; leaves opposite, simple or rarely pinnate, without or rarely with stipules, deciduous. XXXVI. Hippocastanaceæ ([p. 702]). Flowers perfect, irregular; calyx 5-lobed; petals 4 or 5, unequal; fruit a 3-celled 3-valved capsule; leaves opposite, digitately compound, long-petiolate, without stipules, deciduous. XXXVII. Sapindaceæ ([p. 711]). Flowers polygamous; calyx 4 or 5-lobed; corolla of 4 or 5 petals; fruit a berry (Sapindus and Exothea), a drupe (Hypelate), or a 3-valved capsule (Ungnadia); leaves alternate, compound, without stipules, persistent, or deciduous (Ungnadia). XXXVIII. Rhamnaceæ ([p. 718]). Flowers usually perfect; calyx 4 or 5-lobed; petals 4 or 5 (0 in Reynosia, Condalia, and Krugiodendron); fruit drupaceous; leaves simple, alternate (mostly opposite in Reynosia and Krugiodendron), with stipules, persistent (deciduous in some species of Rhamnus). XXXIX. Tiliaceæ ([p. 732]). Flowers perfect; sepals and petals 5; fruit a nut-like berry; leaves simple, alternate, mostly oblique at base, with stipules, deciduous. XL. Sterculiaceæ ([p. 749]). Flowers perfect; calyx 5-lobed; petals 0; fruit a 4 or 5-valved dehiscent capsule; leaves simple, alternate, with stipules, persistent. XLI. Theaceæ ([p. 750]). Flowers perfect; sepals and petals 5; fruit a 5-celled woody dehiscent capsule, loculicidally dehiscent; leaves simple, alternate, without stipules, persistent or deciduous. XLII. Canellaceæ ([p. 753]). Flowers perfect; sepals 3; petals 5; filaments united into a tube; fruit a berry; leaves simple, alternate, without stipules, persistent. XLIII. Kœberliniaceæ ([p. 754]). Flowers perfect; sepals and petals 4, minute; leaves bract-like, alternate, without stipules, caducous. XLIV. Caricaceæ ([p. 755]). Flowers unisexual or perfect; calyx 5-lobed; petals 5; fruit baccate; leaves palmately lobed or digitate, alternate, without stipules, persistent.

B. Ovary inferior (partly inferior in Rhizophora).

XLV. Cactaceæ ([p. 757]). Flowers perfect; petals and sepals numerous; fruit a berry; leaves usually wanting. XLVI. Rhizophoraceæ ([p. 763]). Flowers perfect; calyx 4-parted; petals 4; ovary partly inferior; fruit a 1-celled 1-seeded berry perforated at apex by the germinating embryo; leaves simple, opposite, entire, with stipules, persistent. XLVII. Combretaceæ ([p. 764]). Flowers perfect or polygamous; calyx 5-lobed; petals 5 (0 in Conocarpus); fruit drupaceous; leaves simple, alternate or opposite, without stipules, persistent. XLVIII. Myrtaceæ ([p. 768]). Flowers perfect; calyx usually 4-lobed, or reduced to a single body forming a deciduous lid to the flower (Chytraculia); petals usually 4 (0 in Chytraculia); fruit a berry; leaves simple, opposite, pellucid-punctate, without stipules, persistent. XLIX. Melastomaceæ ([p. 776]). Flowers perfect; calyx and corolla 4 or 5-lobed; stamens as many or twice as many as the lobes of the corolla; fruit capsular or baccate, inclosed in the tube of the calyx; leaves opposite, rarely verticillate, 3—9-nerved, without stipules. L. Araliaceæ ([p. 777]). Flowers perfect or polygamous; sepals and petals usually 5; fruit a drupe; leaves twice pinnate, alternate, with stipules, deciduous. LI. Nyssaceæ ([p. 779]). Flowers diœcious, polygamous, diœcious or perfect; calyx 5-toothed or lobed; petals 5 or more, imbricate in the bud, or 0; stamens as many or twice as many as the petals; fruit drupaceous (Nyssa), usually 1-celled and 1-seeded; leaves alternate, deciduous, without stipules. LII. Cornaceæ ([p. 784]). Flowers perfect or polygamo-diœcious; calyx 4 or 5-toothed; petals 4 or 5; fruit a fleshy drupe; leaves simple, opposite (alternate in one species of Cornus), without stipules, deciduous.

Section 2. Gamopetalæ. Corolla of united petals (divided in Elliottia in Ericaceæ, 0 in some species of Fraxinus in Oleaceæ).

A. Ovary superior (inferior in Vaccinium in Ericaceæ, partly inferior in Symplocaceæ and Styracaceæ).

LIII. Ericaceæ ([p. 790]). Flowers perfect; calyx and corolla 5-lobed (in Elliottia corolla of 4 petals); (ovary inferior in Vaccinium); fruit capsular, drupaceous or baccate; leaves simple, alternate, without stipules, persistent (deciduous in Elliottia and Oxydendrum). LIV. Theophrastaceæ ([p. 804]). Flowers perfect, with staminodia; sepals and petals 5; stamens 5; fruit a berry; leaves simple, opposite or alternate, entire, without stipules. LV. Myrsinaceæ ([p. 805]). Flowers perfect; calyx and corolla 5-lobed; stamens 5; fruit a drupe; leaves simple, alternate, entire, without stipules, persistent. LVI. Sapotaceæ ([p. 808]). Flowers perfect; calyx 5-lobed; corolla 5-lobed (6-lobed in Mimusops), often with as many or twice as many internal appendages borne on its throat; fruit a berry; leaves simple, alternate, without stipules, persistent (deciduous in some species of Bumelia). LVII. Ebenaceæ ([p. 820]). Flowers perfect, diœcious, or polygamous; calyx and corolla 4-lobed; fruit a 1 or several-seeded berry; leaves simple, alternate, entire, without stipules, deciduous. LVIII. Styraceæ ([p. 824]). Flowers perfect; calyx 4 or 5-toothed; corolla 4 or 5-lobed or divided nearly to the base, or rarely 6 or 7-lobed; ovary superior or partly superior; fruit a drupe; leaves simple, alternate, without stipules, deciduous; pubescence mostly scurfy or stellate. LIX. Symplocaceæ ([p. 830]). Flowers perfect; calyx and corolla 5-lobed; ovary inferior or partly inferior; fruit a drupe; leaves simple, alternate, without stipules, deciduous; pubescence simple. LX. Oleaceæ ([p. 832]). Flowers perfect or polygamo-diœcious; calyx 4-lobed (0 in some species of Fraxinus); corolla 2—6-parted (0 in some species of Fraxinus); fruit a winged samara (Fraxinus) or a fleshy drupe (Forestiera, Chionanthus and Osmanthus); leaves pinnate (Fraxinus) or simple, opposite, without stipules, deciduous (persistent in Osmanthus). LXI. Borraginaceæ ([p. 858]). Flowers perfect or polygamous; calyx and corolla 5-lobed; fruit a drupe; leaves simple, alternate, scabrous-pubescent, without stipules, persistent or tardily deciduous. LXII. Verbenaceæ ([p. 864]). Flowers perfect; calyx 5-lobed; corolla 4 or 5-lobed; fruit a drupe or a 1-seeded capsule; leaves simple, opposite, without stipules, persistent. LXIII. Solanaceæ ([p. 867]). Flowers perfect; calyx campanulate, usually 5-lobed; corolla usually 5-lobed; fruit baccate, surrounded at base by the enlarged calyx; leaves alternate, rarely opposite, without stipules. LXIV. Bignoniaceæ ([p. 868]). Flowers perfect; calyx bilabiate; corolla bilabiate, 5-lobed; fruit a woody capsule (Catalpa and Chilopsis) or a berry (Enallagma); leaves simple, opposite (sometimes alternate in Chilopsis), without stipules, deciduous (persistent in Enallagma).

B. Ovary inferior (partly superior in Sambucus in Caprifoliaceæ).

LXV. Rubiaceæ ([p. 875]). Flowers perfect; calyx and corolla 4 or 5-lobed; fruit a capsule (Exostema and Pinckneya), a drupe (Guettarda), or nut-like (Cephalanthus); leaves simple opposite, or in verticils of 3 (Cephalanthus), with stipules, persistent (deciduous in Pinckneya and Cephalanthus). LXVI. Caprifoliaceæ ([p. 882]). Flowers perfect; calyx and corolla 5-lobed; fruit a drupe; leaves unequally pinnate (Sambucus) or simple (Viburnum), opposite, without stipules, deciduous in North American species.

ANALYTICAL KEY
TO THE GENERA OF PLANTS INCLUDED IN THIS BOOK, BASED CHIEFLY ON THE CHARACTER OF THE LEAVES

I. Leaves parallel-veined, alternate, persistent, clustered at the end of the stem or branches. Monocotyledons. Stem simple; leaves stalked. Leaves fan-shaped. Leaf stalks unarmed. Rachis short; leaves usually silvery white below. Leaves 2°—4° in diameter (green below in No. 2), their segments undivided at apex.Thrinax ([p. 96]). Leaves 18′—24′ in diameter, their segments divided at apex.Coccothrinax ([p. 100]). Rachis elongated; leaves green below, their segments divided at apex.Sabal ([p. 101]). Leaf stalks armed with marginal teeth or spines. Leaf stalks furnished irregularly with broad thin large and small, straight or hooked spines confluent into a thin bright orange-colored cartilaginous margin; leaves longer than wide, divided nearly to the middle into segments parted at apex and separating on the margins into thin fibres.Washingtonia ([p. 104]). Leaf stalks furnished with stout or slender flattened teeth; leaves suborbicular, divided to the middle or nearly to the base into segments parted at apex; segments of the blade not separating on the margin into thin fibres.Acœlorraphe ([p. 105]). Leaves pinnate. Leaves 10°—12° in length, their pinnæ 2½°—3° long and often 1½° wide, deep green.Roystonea ([p. 107]). Leaves 5°—6° long, their pinnæ 18′ long and 1′ wide, dark yellow-green above, pale and glaucous below.Pseudophœnix ([p. 109]). Stem simple or branched; leaves sessile, lanceolate, long- and usually sharp-pointed at apex.Yucca ([p. 110]).

II. Leaves 1-nerved, needle-shaped, linear or scale-like, persistent (deciduous in Larix and Taxodium). Gymnospermæ.

1. Leaves Persistent.

a Leaves fascicled, needle-shaped, in 1—5-leafed clusters enclosed at base in a membranaceous sheath.Pinus ([p. 2]). aa Leaves scattered, usually linear. b Leaves linear, often obtuse or emarginate. Base of the leaves persistent on the branches. Leaves sessile, 4-sided, or flattened and stomatiferous above.Picea ([p. 34]). Leaves stalked, flattened and stomatiferous below, or angular, often appearing 2-ranked.Tsuga ([p. 42]). Base of the leaves not persistent on the branches; leaves often appearing 2-ranked. Leaves stalked, flattened, stomatiferous below; winter-buds pointed, not resinous.Pseudotsuga ([p. 47]). Leaves sessile, flattened and often grooved on the upper side, or quadrangular, rarely stomatiferous above, on upper fertile branches often crowded; winter-buds obtuse, resinous (except in No. 9).Abies ([p. 50]). bb Leaves linear-lanceolate, rigid, acuminate, spirally disposed, appearing 2-ranked by a twist in the petiole. Leaves abruptly contracted at base, long-pointed, with pale bands of stomata on the lower surface on each side of the midveins; fruit drupe-like.Torreya ([p. 91]). Leaves gradually narrowed at base, short-pointed, paler, and without distinct bands of stomata on the lower surface; fruit berry-like.Taxus ([p. 93]). bbb Leaves ovate-lanceolate and scale-like, spreading in 2 ranks or linear on the same tree, acute, compressed, keeled on the back and closely appressed or spreading at apex.Sequoia ([p. 61]). aaa Leaves opposite or whorled, usually scale-like.

Internodes distinctly longer than broad; branchlets flattened, of nearly equal color on both sides; leaves eglandular.Libocedrus ([p. 65]). Internodes about as long as broad, often pale below, usually glandular. Branchlets flattened. Branchlets in one plane, much flattened, ¹/₁₂′—⅙′ broad.Thuya ([p. 67]). Branchlets slightly flattened, ¹/₂₄′—¹/₁₆′ broad.Chamæcyparis ([p. 75]). Branchlets terete or 4-angled. Branchlets more or less in one plane; fruit a cone.Cupressus ([p. 69]). Branchlets not in one plane; fruit a berry (leaves needle-shaped, in whorls of 3 in No. 1).Juniperus ([p. 78]).

2. Leaves Deciduous.

Leaves in many-leafed clusters on short lateral spurs.Larix ([p. 31]). Leaves spreading in 2 ranks.Taxodium ([p. 63]).

III. Leaves netted-veined, rarely scale-like or wanting. Dicotyledons.

A. LEAVES OPPOSITE. (B, see [p. xix]).

1. Leaves Simple. (2, see [p. xviii]).

Leaves persistent.

a Leaves with stipules. b Leaves entire or occasionally slightly crenate or serrate. c Leaves emarginate at apex, very short-stalked, 1½′—2′ long. Leaves obovate, gradually narrowed into the petiole.Gyminda ([p. 678]). Leaves oval to oblong, rounded or broad-cuneate (rarely alternate). Branchlets densely velutinous.Krugiodendron ([p. 721]). Branchlets slightly puberulous at first, soon glabrous.Reynosia ([p. 720]). cc Leaves not emarginate at apex. Leaves obtuse, rarely acutish or abruptly short-pointed. Leaves elliptic, 3½′—5′ long.Rhizophora ([p. 763]). Leaves obovate, usually rounded at apex, ¾′—2′ long.Byrsonima ([p. 632]). Leaves acute to acuminate. Leaves oblong-ovate to lanceolate; branchlets glabrous.Exostema ([p. 877]). Leaves broad-elliptic to oblong-elliptic; branchlets villose.Guettarda ([p. 879]). bb Leaves serrate (often pinnate).Lyonothamnus ([p. 378]). aa Leaves without stipules. Petioles biglandular; leaves obtuse or emarginate, 1½′—2½′ long.Laguncularia ([p. 767]). Petioles without glands. Leaves furnished below with small dark glands, slightly aromatic; petioles short. Leaves oblong to oblong-ovate and acuminate or elliptic and bluntly short-pointed.Calyptranthes ([p. 769]). Leaves ovate, obovate or elliptic.Eugenia ([p. 770]). Leaves without glands. Leaves green and glabrous below. Leaves obtuse or emarginate at apex (rarely alternate), 1′—1½′ long.Torrubia ([p. 341]). Leaves acute, acuminate, or sometimes rounded or emarginate, 3′—5′ long. Leaves distinctly veined.Citharexylon ([p. 864]). Leaves obscurely veined.Osmanthus ([p. 856]). Leaves hoary tomentulose or scurfy below. Leaves strongly 3-nerved, acuminate, densely scurfy below.Tetrazygia ([p. 776]). Leaves penniveined, rounded or acute at apex, hoary tomentulose below.Avicennia ([p. 865]).

** Leaves deciduous. a Leaves without lobes. b Leaves serrate. Winter-buds with several opposite outer scales. Leaves puberulous below, closely and finely serrate; axillary buds solitary.Evonymus ([p. 675]). Leaves glabrous below, remotely crenate-serrulate; axillary buds several, superposed.Forestiera ([p. 853]). Winter-buds enclosed in 2 large opposite scales.Viburnum ([p. 886]). bb Leaves entire. c Leaves without stipules. Leaves suborbicular or elliptic to oblong. Leaves rounded or acutish at apex, 1′—2′ long, occasionally 3-foliolate, glabrous; branchlets quadrangular.Fraxinus anomala ([p. 837]). Leaves acuminate or acute at apex, 3′—4′ long. Leaf-scars connected by a transverse line, with 3 bundle-traces; branchlets slender, appressed-pubescent.Cornus ([p. 785]). Leaf-scars not connected, with 1 bundle-trace; branchlets stout, villose, puberulous or glabrous.Chionanthus ([p. 855]). Leaves broad-ovate, cordate, acuminate, 5′—12′ long, on long petioles.Catalpa ([p. 870]). Leaves linear to linear-lanceolate, short-stalked or sessile (sometimes alternate).Chilopsis ([p. 869]). cc Leaves with persistent stipules, entire. Leaves oval or ovate; winter-buds resinous, the terminal up to ½′ in length.Pinckneya ([p. 876]). Leaves ovate to lanceolate; winter-buds minute.Cephalanthus ([p. 878]). aa Leaves palmately lobed.Acer ([p. 681]).

2. Leaves Compound.

a Leaves persistent, with stipules. Leaves equally pinnate; leaflets entire.Guaiacum ([p. 630]). Leaves unequally pinnately parted into 3—8 linear-lanceolate segments (sometimes entire).Lyonothamnus ([p. 378]). Leaves trifoliate. Leaflets stalked.Amyris ([p. 640]). Leaflets sessile.Helietta ([p. 637]). aa Leaves deciduous. Leaves unequally pinnate or trifoliate. Leaflets crenate-serrate or entire, the veins arching within the margins; stipules wanting; winter-buds with several opposite scales.Fraxinus ([p. 833]). Leaflets sharply or incisely serrate, the primary veins extending to the teeth. Leaflets 3—7, incisely serrate; stipules present; winter-buds with 1 pair of obtuse outer scales.Acer Negundo ([p. 699]). Leaflets 5—9, sharply serrate; stipules present; winter-buds with many opposite acute scales; pith thick.Sambucus ([p. 882]). Leaves digitate, with 5—7, sharply serrate leaflets; terminal buds large.Æsculus ([p. 702]).

B. LEAVES ALTERNATE.

1. Leaves Simple. (2, see [p. xxiv]).

* Leaves persistent. (** see [p. xxii]).

a Leaves deeply 3—5-lobed, ⅓′—½′ long, with linear lobes, hoary tomentose below.Cowania ([p. 549]). aa Leaves palmately lobed. Leaves stellate-pubescent, about 1½′ in diameter, with stipules.Fremontia ([p. 749]). Leaves glabrous, 1°—2° in diameter, without stipules.Carica ([p. 755]). aaa Leaves not lobed or pinnately lobed. b Branches spinescent. Leaves clustered at the end of the branches, at least 2′—3′ long.Bucida ([p. 765]). Leaves fascicled on lateral branchlets, obtuse or emarginate, pale and glabrous beneath.Bumelia angustifolia ([p. 816]). Leaves scattered. Leaves generally obovate, mucronate, not more than ½′—1′ long, glabrous and green or brownish tomentulose beneath.Condalia ([p. 719]). Leaves elliptic-ovate to oblong, obtuse or emarginate, glabrous, 1—2 cm. long.Ximenia ([p. 337]). bb Branches not spinescent. c Leaves serrate, or lobed (in some species of Quercus). (cc, see [p. xxii]). d Juice watery. (dd, see [p. xxii]). e Stipules present. (ee, see [p. xxii]). f Primary veins extending straight to the teeth. Leaves and branchlets glabrous or pubescent to tomentose with fascicled hairs. Leaves fulvous-tomentose beneath, repand-dentate, 3′—5′ long.Lithocarpus ([p. 236]). Leaves glabrous or grayish to whitish tomentose beneath, entire, lobed or dentate.Quercus sp. 21—34 ([p. 268]). Leaves and branchlets coated with simpled silky or woolly hairs at least while young, not more than 2½′ long.Cercocarpus ([p. 550]). ff Primary veins arching and united within the margin. Leaves 3-nerved from the base.Ceanothus ([p. 726]). Leaves not 3-nerved. Leaves acute. Leaves sinuately dentate, with few spiny teeth (rarely entire), glabrous.Ilex opaca ([p. 669]). Leaves serrate. Leaves tomentose below; branchlets tomentose. Leaves narrow-lanceolate, glabrous and smooth above.Vauquelinia ([p. 377]). Leaves ovate, cordate, scabrate above.Trema ([p. 327]). Leaves glabrous below.Heteromeles ([p. 392]). Leaves entire, very rarely toothed. Leaves elliptic, glabrous.Prunus caroliniana ([p. 579]). Leaves oblanceolate, pubescent beneath when young.Ilex Cassine ([p. 670]). Leaves obtuse, sometimes mucronate. Leaves spinose-serrate, glabrous. Leaves broad-ovate to suborbicular or elliptic; branchlets dark red-brown, spinescent.Rhamnus crocea ([p. 723]). Leaves ovate to ovate-lanceolate; branchlets yellow or orange-colored, not spinescent.Prunus ilicifolia ([p. 581]). Leaves crenate (often entire), oval to oblong.Ilex vomitoria ([p. 671]). ee Stipules wanting. Leaves resinous-dotted, aromatic, 1½′—4′ long.Myrica ([p. 163]). Leaves not resinous-dotted, crenately serrate, 4′—6′ long. Leaves dark green, glabrous below.Gordonia Lasianthus ([p. 751]). Leaves yellowish green, pubescent below, sometimes nearly entire.Symplocos ([p. 831]). dd Juice milky. Petioles 2½′—4′ long; leaves broad-ovate.Hippomane ([p. 652]). Petioles about ¼′ long; leaves elliptic to oblong-lanceolate.Gymnanthes ([p. 654]). cc Leaves entire (rarely sparingly toothed on vigorous branchlets). d Stipules present. e Stipules connate, at least at first. Stipules persistent, forming a sheath surrounding the branch above the node; leaves obtuse.Coccolobis ([p. 338]). Stipules deciduous, enveloping the unfolded leaf. Leaves ferrugineous-tomentose beneath.Magnolia grandiflora ([p. 345]). Leaves glabrous beneath, with milky juice.Ficus ([p. 333]). ee Stipules free. f Juice milky; leaves oval to oblong, 3′—5′ long.Drypetes ([p. 650]). ff Juice watery. g Leaves obtuse or emarginate at apex. Leaves with ferrugineous scales beneath, their petioles slender.Capparis ([p. 365]). Leaves without ferrugineous scales. Leaves soft-pubescent on both sides.Colubrina cubensis ([p. 730]). Leaves glabrous at least at maturity. Leaves rarely 2′—3′ long, standing on the branch at acute angles.Chrysobalanus ([p. 583]). Leaves rarely more than 1′ long, spreading (sometimes 3-nerved).Ceanothus spinosos ([p. 728]). gg Leaves acute or acutish.

Petioles with 2 glands.Conocarpus ([p. 766]). Petioles without glands. Leaves and branchlets more or less pubescent, at least while young. Leaves fascicled except on vigorous branchlets.Cercocarpus ([p. 550]). Leaves not fascicled. Winter-buds minute, with few pointed scales. Leaves rounded or nearly rounded at base.Colubrina sp. 1, 3 ([p. 729]). Leaves broad-cuneate at base.Ilex Cassine ([p. 670]). Winter-buds conspicuous, with numerous scales. Leaves usually lanceolate, entire, covered below with yellow scales.Castanopsis ([p. 234]). Leaves oblong or oblong-obovate, repand-dentate, fibrous tomentose below.Lithocarpus ([p. 236]). Leaves and branchlets glabrous. Leaf-scar with 1 bundle-trace.Ilex Krugiana ([p. 672]). Leaf-scar with 3 bundle-traces. Cherry Laurels.Prunus sp. 19—22 ([p. 579]). dd Stipules wanting. e Leaves aromatic when bruised. Leaves resinous-dotted.Myrica ([p. 163]). Leaves not resinous-dotted. Leaves obtuse, obovate, glabrous.Canella ([p. 753]). Leaves acute. Leaves mostly rounded at the narrowed base, ovate to oblong, acute, glabrous.Anona ([p. 354]). Leaves more or less cuneate at base, elliptic to lanceolate, usually acuminate. Leaves abruptly long-acuminate, glabrous, the margin undulate; branchlets red-brown.Misanteca ([p. 364]). Leaves gradually acuminate or nearly acute. Leaves strongly reticulate beneath. Branchlets glabrous, light grayish brown; leaves glabrous, light green beneath.Ocotea ([p. 359]). Branchlets pubescent while young, greenish or yellowish; leaves pale beneath, pubescent while young.Umbellularia ([p. 360]). Leaves not or slightly reticulate, glaucous, glabrous or pubescent beneath.Persea ([p. 356]).

ee Leaves not aromatic. f Leaves acute or acutish. Leaves obovate, gradually narrowed into short petioles. Leaves 2′—2½′ long.Schæfferia ([p. 679]). Leaves at least 6′—8′ long.Enallagma ([p. 873]). Leaves elliptic to oblong or ovate. Leaves rough or pubescent above, pubescent below, subcordate to cuneate at base. Leaves stellate-pubescent.Solanum ([p. 867]). Leaves scabrous above. Petiole ⅛′—¼′ long; leaves oval or oblong, 1¼′—4′ long.Ehretia ([p. 862]). Petiole 1′—1½′ long; leaves ovate to oblong-ovate, 3′—7′ long.Cordia ([p. 858]). Leaves smooth above. Winter-buds scaly. Leaves covered below with ferrugineous or pale scales, 1′—3′ long.Lyonia ([p. 797]). Leaves glabrous or nearly so below. Leaves ovate-lanceolate or obovate-lanceolate, 4′—12′ long, usually clustered at end of branchlet, veinlets below obscure.Rhododendron ([p. 792]). Leaves elliptic or oval to oblong or lanceolate. Leaves light yellowish green below and without distinctly visible veins or veinlets, entire, 3′—4′ long.Kalmia ([p. 794]). Leaves pale below and more or less distinctly reticulate, occasionally serrate or denticulate, 1′—5′ long; bark of branches red.Arbutus ([p. 799]). Winter-buds naked. Leaves pubescent below when unfolding. Mature leaves nearly glabrous below. Leaves oblong-lanceolate to narrow-obovate.Dipholis ([p. 810]). Leaves oval.Sideroxylum ([p. 809]). Mature leaves covered below with brilliant copper-colored pubescence. Leaves glabrous below.Chrysophyllum ([p. 817]). Leaves marked by minute black dots, ovate to oblong-lanceolate.Ardisia ([p. 806]). Leaves lepidote, oblong-obovate.Rapanea ([p. 807]). ff Leaves obtuse or emarginate at apex. g Leaves rounded or cordate at base, emarginate, their petioles slender. Leaves reniform to broad-ovate, cordate; juice watery.Cercis ([p. 603]). Leaves elliptic to oblong, rounded at base; juice milky or viscid. Leaves emarginate; petioles slender, rufous-tomentulose.Mimusops ([p. 819]). Leaves obtuse at apex; petioles stout, grayish-tomentulose or glabrous.Rhus integrifolia ([p. 664]). gg Leaves cuneate at base.

Petioles slender, ½′ long.Beureria ([p. 861]). Petioles short and stout. Leaves coriaceous, with thick revolute margins (sometimes opposite).Jacquinia ([p. 804]). Leaves subcoriaceous, slightly revolute. Leaves reticulate-veined beneath. Leaves oval to obovate or oblong-oval, more or less pubescent while young.Vaccinium ([p. 802]). Leaves oblong to oblong-obovate, glabrous.Cyrilla ([p. 666]). Leaves obscurely veined beneath, glabrous. Leaves oblong-lanceolate, narrowed toward the emarginate apex, decurrent nearly to base of petiole.Cliftonia ([p. 667]). Leaves rounded at apex, distinctly petioled.Maytenus ([p. 676]).

** Leaves deciduous.

† Leaves conspicuous. (††, see [p. xxiv].)

a Leaves entire, sometimes 3 or 4-lobed. (aa, see [p. xxiii]). b Stipules present. Juice milky.Maclura ([p. 331]). Juice watery. Stipules connate, enveloping the young leaves, their scars encircling the branchlet. Leaves acute or acuminate, entire; winter-buds pointed, nearly terete.Magnolia ([p. 342]). Leaves truncate, sinuately 4-lobed; winter-buds obtuse, compressed.Liriodendron ([p. 351]). Stipules distinct. Branches spinescent; leaves glandular, caducous (crenately serrate on vigorous shoots).Dalea ([p. 621]). Branches not spinescent; leaves without glands. Winter-buds with a single pair of connate scales.Salix ([p. 138]). Winter-buds with several pairs of imbricate scales. Branchlets without a terminal bud; leaves 3-nerved.Celtis ([p. 318]). Branchlets with a terminal bud, leaves penniveined.Quercus sp. 17—20 ([p. 262]). bb Stipules wanting. c Branchlets bright green and lustrous for the first 2 or 3 years; leaves sometimes 3-lobed, aromatic.Sassafras ([p. 362]). cc Branchlets brown or gray. d Leaves acute or acuminate. Leaves 10′—12′ long, obovate-oblong, acuminate, glabrous, emitting a disagreeable odor.Asimina ([p. 353]). Leaves smaller. Petioles very slender, 1′—2′ long; leaves elliptic, acuminate.Cornus alternifolia ([p. 789]). Petioles short. Branchlets with a terminal bud. Leaf-scars about as long as broad; branchlets without lenticels, light reddish brown.Elliottia ([p. 791]). Leaf-scars crescent-shaped, broader than long, with 3 distinct bundle-traces. Leaves pubescent on both sides, rugulose above; petioles 1′—2′ long, like the young branchlet densely pubescent.Leitneria ([p. 167]). Leaves glabrous and smooth above, glabrous or pubescent below; petioles and branchlets usually glabrous or nearly so at maturity.Nyssa ([p. 779]). Branchlets without a terminal bud. Pubescence consisting of simple hairs or wanting. Leaves 4′—6′ long, pubescent beneath while young; branchlet light brown or gray.Diospyros virginiana ([p. 821]). Leaves 1½′—3′ long, glabrous; branches light yellowish gray.Schœpfia ([p. 336]). Pubescence stellate; leaves obovate or elliptic, 2½′—5′ long, pubescent below.Styrax ([p. 829]). dd Leaves obtuse or acute. Branchlets not spinescent. Leaves glabrous at maturity, their petioles slender.Cotinus ([p. 657]). Leaves pubescent below at maturity; their petioles short and thick.Diospyros texana ([p. 823]). Branchlets spinescent; leaves often fascicled on lateral branchlets.Bumelia ([p. 812]). aa Leaves serrate or pinnately lobed. b Stipules present. (bb, see [p. xxvi].) c Winter-buds naked. Leaves oblique at base, the upper side rounded or subcordate, obovate, coarsely toothed.Hamamelis ([p. 368]). Leaves equal at base, cuneate, finely serrate or crenate.Rhamnus sp. 2, 3 (p. [724], [725]). cc Winter-buds with a single pair of connate scales. Primary veins arching and uniting within the margins; leaves simply serrate or crenate, sometimes entire.Salix ([p. 138]). Primary veins extending to the teeth, leaves doubly serrate, often slightly lobed.Alnus ([p. 220]). ccc Winter-buds with several pairs of imbricate scales. d Terminal buds wanting; branchlets prolonged by an upper axillary bud. Juice milky; leaves usually ovate, often lobed.Morus ([p. 328]). Juice watery; leaves not lobed. Leaves distinctly oblique at base. Leaves with numerous prominent lateral veins. Leaves generally broad-ovate, simply serrate, stellate-pubescent at least while young, rarely glabrous.Tilia ([p. 732]). Leaves never broad-ovate, usually doubly serrate, more or less pubescent with simple hairs, at least while young. Winter-buds ovoid, usually acute, ⅓ to nearly as long as petioles; leaves 1′—7′ long, doubly serrate.Ulmus ([p. 309]). Winter-buds subglobose, minute; leaves 2′—2½′ long, crenate-serrate.Planera ([p. 316]). Leaves 3 or 4-nerved from the base.Celtis ([p. 318]). Leaves slightly or not at all oblique at base. Leaves 3-nerved from the base, glandular-crenate or glandular-serrate.Ceanothus ([p. 726]). Leaves not or obscurely 3-nerved at base, usually doubly serrate. Leaves blue-green; petioles ¼′—½′ long; bark smooth, gray-brown.Carpinus ([p. 201]). Leaves yellow-green. Bark rough, furrowed; petioles ⅛′—¼′ long; leaves not resinous-glandular.Ostrya ([p. 202]). Bark flaky or cherry-tree like; petioles ¼′—1′ long; leaves often resinous-glandular while young.Betula ([p. 205]). dd Terminal buds present. Primary veins arching and uniting within the margin (extending to the margin in the lobed leaves of Malus). Winter-buds resinous; leaves crenate, usually truncate at base; petioles slender.Populus ([p. 119]). Winter-buds not resinous. Leaf-scars with 3 bundle-traces. Leaves involute in bud, often lobed on vigorous shoots; winter-buds obtuse, short, pubescent.Malus ([p. 379]). Leaves conduplicate (or in some species of Prunus convolute), never lobed; winter-buds acute. Winter-buds elongated; branches never spinescent.Amelanchier ([p. 393]). Winter-buds not elongated, ovoid; branches sometimes spinescent.Prunus ([p. 555]). Leaf-scars with 1 bundle-trace; leaves simply serrate.Ilex sp. 5—6 ([p. 673]).

Primary veins extending to the teeth or to the lobes. Leaves lobed.Quercus sp. 1—16, 35—50 (p. [241], [283]). Leaves serrate-toothed. Winter-buds with numerous scales. Leaves lustrous beneath, remotely serrate or denticulate; winter-buds elongated, acuminate.Fagus ([p. 228]). Leaves pale beneath, coarsely dentate or serrate; winter-buds acute. Chestnut Oaks.Quercus sp. 51—54 ([p. 303]). Winter-buds with 2 pairs of scales.Castanea ([p. 230]). Leaves doubly or simply serrate, or lobed, with serrate lobes; branches often furnished with spines. Leaves involute in the bud; branchlets often ending in blunt spines.Malus ([p. 379]). Leaves conduplicate in the bud; branches usually armed with sharp-pointed single or branched axillary spines.Cratægus ([p. 397]). bb Stipules wanting. c Leaves not lobed. Leaves subcoriaceous, oblong, sometimes nearly entire, glabrous.Symplocos ([p. 831]). Leaves thin. Leaves oblong-obovate, acute, pubescent beneath.Gordonia alatamaha ([p. 752]). Leaves oblong or lanceolate, acuminate, glabrous or puberulous while young, turning scarlet in the autumn.Oxydendrum ([p. 796]). Leaves ovate to elliptic, stellate-pubescent or glabrous, turning yellow in the autumn.Halesia ([p. 824]). cc Leaves palmately lobed. Stipules large, foliaceous, united; branchlets without a terminal bud.Platanus ([p. 371]). Stipules small, free, caducous; branchlets with a terminal bud.Liquidambar ([p. 367]).

†† Leaves inconspicuous or wanting; branches spiny or prickly.

Branches or stems succulent, armed with numerous prickles. Branches and stems columnar, ribbed, continuous; leaves 0.Cereus ([p. 757]). Branches jointed, tuberculate; leaves scale-like.Opuntia ([p. 759]). Branches rigid, spinescent. Leaves minute, narrow-obovate. Branchlets bright green.Kœberlinia ([p. 754]). Branchlets red-brown.Dalea ([p. 621]). Leaves scale-like, caducous.Canotia ([p. 677]).

2. Leaves compound.

* Leaves 3-foliolate, without stipules.

Leaves persistent; leaflets obovate, entire, sessile.Hypelate ([p. 716]). Leaves deciduous. Leaflets deltoid to hastate, entire, rounded at apex; branches prickly.Erythrina ([p. 627]). Leaflets ovate to oblong, acuminate, strongly scented and bitter; branches unarmed.Ptelea ([p. 639]).

** Leaves twice pinnate; stipules present.

a Leaves unequally twice pinnate, 2°—4° long, deciduous; leaflets serrate, 2′—3′ in length; branches and stem armed with scattered prickles.Aralia ([p. 778]). aa Leaves equally twice pinnate, usually smaller; branches unarmed or armed with stipular or axillary spines (in Parkinsonia often apparently simply pinnate). b Leaflets crenate; leaves simply or twice-pinnate on the same plant, deciduous, usually armed with simple or branched axillary spines.Gleditsia ([p. 607]). bb Leaflets entire. Leaflets 2—2½′ long; leaves deciduous; branchlets stout, unarmed.Gymnocladus ([p. 605]). Leaflets smaller; leaves usually persistent; branchlets slender. Branches armed with prickles or spines. Leaves with 2 or rarely 4 pinnæ. Branches armed with axillary spines or spiny rachises. Pinnæ with 4—8 leaflets; branches with short axillary spines.Cercidium ([p. 613]). Pinnæ with 8—60 leaflets; branches armed with spiny rachises or rigid branchlets terminating in stout spines.Parkinsonia ([p. 611]). Branches armed with stipular prickles; leaves persistent. Pinnæ with many oblong to linear leaflets.Prosopis ([p. 599]). Pinnæ with 1 pair of orbicular to broad-oblong leaflets.Pithecolobium unguis-cati ([p. 586]). Leaves with 6, or more, rarely 4, pinnæ. Prickles usually spreading, often recurved.Acacia ([p. 591]). Prickles usually more or less ascending, straight.Pithecolobium ([p. 586]). Branches unarmed. Branchlets and petioles glabrous; leaves with 2—5 pair of pinnæ, each with 40—80 leaflets.Lysiloma ([p. 589]). Branchlets and petioles pubescent while young; leaves with 5—17 pair of many-foliolate pinnæ, or pinnæ 2—4 and each with 8—16 leaflets.Leucæna ([p. 596]).

*** Leaves simply pinnate.

a Leaves equally pinnate. Stipules wanting. Leaflets 2—4, generally oblong-obovate.Exothea ([p. 714]). Leaflets 6—12. Leaflets obtuse, usually oblong-obovate. Leaflets 8—12, 2′—3′ long, pale below; leaves occasionally opposite.Simarouba ([p. 642]). Leaflets 6—8, 1′—1½′ long, green below.Xanthoxylum coriaceum ([p. 637]). Leaflets 6—8, acuminate.Swietenia ([p. 648]). Stipules present. Branches armed with infra-stipular spines in pairs; leaflets 10—15, usually oblong-obovate, ½′—¾′ long, persistent.Olneya ([p. 626]). Branches unarmed; leaflets 20—46, ovals ½′—⅔′ long.Eysenhardtia ([p. 620]). aa Leaves unequally pinnate. b Stipules present. Leaflets sharply serrate; leaves deciduous; winter-buds resinous.Sorbus ([p. 390]). Leaflets entire or crenately serrate. Leaves deciduous. Leaflets 7—11, 3′—4½′ long; branches unarmed. Leaflets usually alternate, thin and glabrous at maturity.Cladrastis ([p. 618]). Leaflets opposite, coriaceous, pubescent beneath at least along the veins.Ichthyomethia ([p. 628]). Leaflets 9—21, 1—2 cm. long. Branches usually with stipular prickles, sometimes viscid.Robinia ([p. 622]). Branches unarmed, not viscid; leaflets 13—19, elliptic.Sophora affinis ([p. 617]). Leaves persistent. Leaflets 7—9, oblong-elliptic, 1′—2½′ long; branches unarmed.Sophora secundiflora ([p. 616]). Leaflets 10—15; branches prickly.Olneya ([p. 626]). bb Stipules wanting. d Leaves persistent. Leaflets long-stalked (sometimes nearly sessile in Xanthoxylum flavum). Leaflets oblong-ovate, cuneate at base. Leaflets acuminate, glabrous.Picramnia ([p. 643]). Leaflets obtuse, tomentose when unfolding.Xanthoxylum flavum ([p. 636]). Leaflets broad-ovate, usually rounded or subcordate at base.Metopium ([p. 658]). Leaflets sessile or nearly so. Petiole and rachis winged. Leaflets crenate, obovate, about ½′ long; branches prickly.Xanthoxylum Fagara ([p. 634]). Leaflets entire. Leaflets oblong, usually acute, 3′—4′ long.Sapindus saponaria ([p. 712]). Leaflets spathulate, rounded at apex, not more than ¾′ long.Pistacia ([p. 656]). Petiole and rachis not winged. Leaflets 7—19, acuminate, 2′—5′ long.Sapindus marginatus ([p. 713]). Leaflets 21—41, obtuse, ½′—¾′ long.Alvaradoa ([p. 644]). dd Leaves deciduous. Leaflets long-stalked, 3—7, entire, acute.Bursera ([p. 645]). Leaflets sessile or nearly so. Branches prickly; leaflets crenate.Xanthoxylum clava-Herculis ([p. 635]). Branches unarmed. Juice milky or viscid; leaflets serrate or entire; rachis sometimes winged.Rhus species 1—3 ([p. 660]). Juice watery. Rachis without wings. Leaflets entire, acuminate, 7—9.Sapindus Drummondii ([p. 714]). Leaflets serrate or crenate. Winter-buds large; leaflets 5—23, aromatic. Winter-buds naked.Juglans ([p. 169]). Winter-buds covered with scales.Carya ([p. 176]). Winter-buds minute, globose, scaly; leaflets 5—7, ovate, not aromatic.Ungnadia ([p. 717]). Rachis winged; leaflets 10—20, entire, rounded at apex, not more than ¼′ long.Bursera microphylla ([p. 647]).

TREES OF NORTH AMERICA
(Exclusive of Mexico)

Class 1. GYMNOSPERMÆ.

Ovules and seeds borne on the face of a scale, not inclosed in an ovary; resinous trees, with stems increasing in diameter by the annual addition of a layer of wood inside the bark.

I. PINACEÆ.

Trees, with narrow or scale-like generally persistent clustered or alternate leaves and usually scaly buds. Flowers appearing in early spring, mostly surrounded at the base by an involucre of the more or less enlarged scales of the buds, unisexual, monœcious (diœcious in Juniperus), the male consisting of numerous 2-celled anthers, the female of scales bearing on their inner face 2 or several ovules, and becoming at maturity a woody cone or rarely a berry. Seeds with or without wings; seed-coat of 2 layers; embryo axile in copious albumen; cotyledons 2 or several. Of the twenty-nine genera scattered over the surface of the globe, but most abundant in northern temperate regions, thirteen occur in North America.

CONSPECTUS OF THE NORTH AMERICAN GENERA.

Scales of the female flowers numerous; spirally arranged in the axils of persistent bracts; ovules 2, inverted; seeds borne directly on the scales, attached at the base in shallow depressions on the inner side of the scales, falling from them at maturity and usually carrying away a scarious terminal wing; leaves fascicled or scattered (deciduous in Larix). Abietineæ. Fruit maturing in two or rarely in three seasons; leaves fascicled, needle-shaped in axillary 1—5-leaved clusters, inclosed at the base in a membranaceous sheath; cone-scales thick and woody, much longer than their bracts.1. [Pinus.] Fruit maturing in one season. Leaves in many-leaved clusters on short spur-like branchlets, deciduous; cone-scales thin, usually shorter than their bracts.2. [Larix.] Leaves scattered, linear. Cones pendulous, the scales persistent on the axis. Branchlets roughened by the persistent leaf-bases; leaves deciduous in drying; bracts shorter than the cone-scales. Leaves sessile, 4-sided, or flattened and stomatiferous above.3. [Picea.] Leaves stalked, flattened and stomatiferous below, or angular.4. [Tsuga.] Branchlets not roughened by leaf-bases; leaves stalked, flattened; not deciduous in drying; bracts of the cone 2-lobed, aristate, longer than the scales.5. [Pseudotsuga.] Cones erect, their scales deciduous from the axis, longer or shorter than the bracts; leaves sessile, flat or 4-sided.6. [Abies.] Scales of the female flowers without bracts; ovules and seeds borne on the face of minute scales adnate to the base of the flower-scales, enlarging and forming the scales of the cone. Seeds with a narrow marginal wing (wingless in Juniperas). Scales of the female flowers numerous, spirally arranged, forming a woody cone; ovules erect, 2 or many under each scale; leaves linear, alternate, often of 2 forms (deciduous in Taxodium). Taxodiæ. Ovules and seeds numerous under each scale.7. [Sequoia.] Ovules and seeds 2 under each scale; leaves mostly spreading in 2 ranks.8. [Taxodium.] Scales of the female flower few, decussate, forming a small cone, or rarely a berry; ovules 2 or many under each scale; leaves decussate or in 3 ranks, often of 2 forms, usually scale-like, mostly adnate to the branch, the earliest free and subulate. Cupressineæ. Fruit a cone; leaves scale-like. Cones oblong, their scales oblong, imbricated or valvate; seeds 2 under each scale, maturing the first year. Scales of the cone 6, the middle ones only fertile; seeds unequally 2-winged.9. [Libocedrus.] Scales of the cone 8—12; seeds equally 2-winged.10. [Thuja.] Cones subglobose, the scales peltate, maturing in one or two years; seeds few or many under each scale. Fruit maturing in two seasons; seeds many under each scale; branchlets terete or 4-winged.11. [Cupressus.] Fruit maturing in one season; seeds 2 under each scale; branchlets flattened.12. [Chamæcyparis.] Fruit a berry formed by the coalition of the scales of the flower; ovules in pairs or solitary; flowers diœcious; leaves decussate or in 3’s, subulate or scale-like, often of 2 forms.13. [Juniperus.]

1. PINUS Duham. Pine.

Trees or rarely shrubs, with deeply furrowed and sometimes laminate or with thin and scaly bark, hard or often soft heartwood often conspicuously marked by dark bands of summer cells impregnated with resin, pale nearly white sapwood, and large branch-buds formed during summer and composed of minute buds in the axils of bud-scales, becoming the bracts of the spring shoot. Leaves needle-shaped, clustered, the clusters borne on deciduous spurs in the axils of scale-like primary leaves, inclosed in the bud by numerous scales lengthening and forming a more or less persistent sheath at the base of each cluster. Male flowers clustered at the base of leafy growing shoots of the year, each flower surrounded at the base by an involucre of 3—6 scale-like bracts, composed of numerous sessile anthers, imbricated in many ranks and surmounted by crest-like nearly orbicular connectives; the female subterminal or lateral, their scales in the axils of non-accrescent bracts. Fruit a woody cone maturing at the end of the second or rarely of the third season, composed of the hardened and woody scales of the flower more or less thickened on the exposed surface (the apophysis), with the ends of the growth of the previous year appearing as terminal or dorsal brown protuberances or scars (the umbo). Seeds usually obovoid, shorter or longer than their wings or rarely wingless; outer seed-coat crustaceous or thick, hard, and bony, the inner membranaceous; cotyledons 3—18, usually much shorter than the inferior radicle.

Pinus is widely distributed through the northern hemisphere from the Arctic Circle to the West Indies, the mountains of Central America, the Canary Islands, northern Africa, the Philippine Islands, and Sumatra. About sixty-six species are recognized. Of exotic species the so-called Scotch Pine, Pinus sylvestris L., of Europe and Asia, the Swiss Stone Pine, Pinus cembra L., and the Austrian Pine and other forms of Pinus nigra Arnold, from central and southern Europe, are often planted in the northeastern states, and Pinus Pinaster Ait., of the coast region of western France and the Mediterranean Basin is successfully cultivated in central and southern California. Pinus is the classical name of the Pine-tree.

The North American species can be conveniently grouped in two sections, Soft Pines and Pitch Pines.

SOFT PINES.

Wood soft, close-grained, light-colored, the sapwood thin and nearly white; sheaths of the leaf-clusters deciduous; leaves with one fibro-vascular bundle.

Leaves in 5-leaved clusters. Cones long-stalked, elongated, cylindric bright green at maturity, becoming light yellow brown, their scales thin, with terminal unarmed umbos; seeds shorter than their wings. White Pines. Leaves without conspicuous white lines on the back. Leaves slender, flexible; cones 4′—8′ long.1. [P. Strobus] (A). Leaves stout, more rigid; cones 5′—11′ long.2. [P. monticola] (B, G). Leaves with conspicuous white lines on the back; cones 12′—18′ long.3. [P. Lambertiana] (G). Cones short-stalked, green or purple at maturity, their scales thick. Cones cylindric or subglobose, their scales with terminal umbos; leaves 2′ long or less. Stone Pines. Cones 3′—10′ long, their scales opening at maturity; seeds with wings.4. [P. flexilis] (F, H). Cones ½′—3′ long, their scales remaining closed at maturity; seeds wingless.5. [P. albicaulis] (B, F, G). Cones ovoid-oblong, their scales with dorsal umbos armed with slender prickles; seeds shorter than their wings; leaves in crowded clusters, incurved, less than 2′ long. Foxtail Pines. Cones armed with minute incurved prickles.6. [P. Balfouriana] (G). Cones armed with long slender prickles.7. [P. aristata] (F, G). Leaves in 1—4-leaved clusters; cones globose, green at maturity, becoming light brown, their scales few, concave, much thickened, only the middle scales seed-bearing; seeds large and edible, their wings rudimentary; leaves 2′ or less, often incurved. Nut Pines.8. [P. cembroides] (C, F, G, H).

1. [Pinus Strobus] L. White Pine.

Leaves soft bluish green, whitened on the ventral side by 3—5 bands of stomata, 3′—5′ long, mostly turning yellow and falling in September in their second season, or persistent until the following June. Flowers: male yellow; female bright pink, with purple scale margins. Fruit fully grown in July of the second season, 4′—8′ long, opening and discharging its seeds in September; seeds narrowed at the ends, ¼′ long, red-brown mottled with black, about one fourth as long as their wings.

A tree, while young with slender horizontal or slightly ascending branches in regular whorls usually of 5 branches; at maturity often 100°, occasionally 220° high, with a tall straight stem 3°—4° or rarely 6° in diameter, when crowded in the forest with short branches forming a narrow head, or rising above its forest companions with long lateral branches sweeping upward in graceful curves, the upper branches ascending and forming a broad open irregular head, and slender branchlets coated at first with rusty tomentum, soon glabrous, and orange-brown in their first winter. Bark on young stems and branches thin, smooth, green tinged with red, lustrous during the summer, becoming 1′—2′ thick on old trunks and deeply divided by shallow fissures into broad connected ridges covered with small closely appressed purplish scales. Wood light, not strong, straight-grained, easily worked, light brown often slightly tinged with red; largely manufactured into lumber, shingles, and laths, used in construction, for cabinet-making, the interior finish of buildings, wooden ware, matches, and the masts of vessels.

Distribution. Newfoundland to Manitoba, southward through the northern states to Pennsylvania, northern and eastern (Belmont County) Ohio, northern Indiana, valley of the Rocky River near Oregon, Ogle County, Illinois, and central and southeastern Iowa, and along the Appalachian Mountains to eastern Kentucky and Tennessee and northern Georgia; forming nearly pure forests on sandy drift soils, or more often in small groves scattered in forests of deciduous-leaved trees on fertile well-drained soil, also on the banks of streams, or on river flats, or rarely in swamps.

Largely planted as an ornament of parks and gardens in the eastern states, and in many European countries, where it grows with vigor and rapidity; occasionally used in forest planting in the United States.

2. [Pinus monticola] D. Don. White Pine.

Leaves blue-green, glaucous, whitened by 2—6 rows of ventral and often by dorsal stomata, mostly persistent 3 or 4 years. Flowers: male yellow; female pale purple. Fruit 5′—11′ long, shedding its seeds late in the summer or in early autumn; seeds narrowed at the ends, ⅓′ long, pale red-brown mottled with black, about one third as long as their wings.

A tree, often 100° or occasionally 150° high, with a trunk frequently 4°—5° or rarely 7°—8° in diameter, slender spreading slightly pendulous branches clothing young stems to the ground and in old age forming a narrow open often unsymmetrical pyramidal head, and stout tough branchlets clothed at first with rusty pubescence, dark orange-brown and puberulous in their first and dark red-purple and glabrous in their second season. Bark of young stems and branches thin, smooth, light gray, becoming on old trees ¾′—1½′ thick and divided into small nearly square plates by deep longitudinal and cross fissures, and covered by small closely appressed purple scales. Wood light, soft, not strong, close, straight-grained, light brown or red; sometimes manufactured into lumber, used in construction and the interior finish of buildings.

Distribution. Scattered through mountain forests from the basin of the Columbia River in British Columbia to Vancouver Island; on the mountains of northern Washington to the western slopes of the Rocky Mountains of northern Montana; on the coast ranges of Washington and Oregon; and on the Cascade and Sierra Nevada ranges southward to the Kern River valley, California; most abundant and of its greatest value in northern Idaho on the bottom-lands of streams tributary to Lake Pend Oreille; reaching the sea-level on the southern shores of the Straits of Fuca and elevations of 10,000° on the California Sierras.

Often planted as an ornamental tree in Europe, and occasionally in the eastern United States where it grows more vigorously than any other Pine-tree of western America.

3. [Pinus Lambertiana] Dougl. Sugar Pine.

Leaves stout, rigid, 3½′—4′ long, marked on the two faces by 2—6 rows of stomata; deciduous during their second and third years. Flowers: male light yellow; female pale green. Fruit fully grown in August and opening in October, 11′—18′ or rarely 21′ long; seeds ½′—⅝′ long, dark chestnut-brown or nearly black, and half the length of their firm dark brown obtuse wings broadest below the middle and ½′ wide.

A tree, in early life with remote regular whorls of slender branches often clothing the stem to the ground and forming an open narrow pyramid; at maturity 200°-220° high, with a trunk 6°—8° or occasionally 12° in diameter, a flat-topped crown frequently 60° or 70° across of comparatively slender branches sweeping outward and downward in graceful curves, and stout branchlets coated at first with pale or rufous pubescence, dark orange-brown during their first winter, becoming dark purple-brown. Bark on young stems and branches thin, smooth, dark green, becoming on old trunks 2′—3′ thick and deeply and irregularly divided into long thick plate-like ridges covered with large loose rich purple-brown or cinnamon-red scales. Wood light, soft, straight-grained, light red-brown; largely manufactured into lumber and used for the interior finish of buildings, woodwork, and shingles. A sweet sugar-like substance exudes from wounds made in the heartwood.

Distribution. Mountain slopes and the sides of ravines and cañons; western Oregon from the valley of the north branch of the Santiam River southward on the Cascade and coast ranges; California along the northern and coast ranges to Sonoma County; along the western slopes of the Sierra Nevada, where it grows to its greatest size at elevations between 3000° and 7000°; reappearing on the Santa Lucia Mountains of the coast ranges; and on the high mountains in the southwestern part of the state from Santa Barbara County southward usually at elevations of 5000°—7000° above the sea; and on the San Pedro Mártir Mountains in Lower California.

Occasionally planted as an ornamental tree in western Europe and in the eastern states, the Sugar Pine has grown slowly in cultivation and shows little promise of attaining the large size and great beauty which distinguish it in its native forests.

4. [Pinus flexilis] James. Rocky Mountain White Pine.

Pinus strobiformis Sarg., not Engelm.

Leaves stout, rigid, dark green, marked on all sides by 1—4 rows of stomata, 1½′—3′ long, deciduous in their fifth and sixth years. Flowers: male reddish; female clustered, bright red-purple. Fruit subcylindric, horizontal or slightly declining, green or rarely purple at maturity, 3′—10′ long, with narrow and more or less reflexed scales opening at maturity; seeds compressed, ⅓′—½′ long, dark red-brown mottled with black, with a thick shell produced into a narrow margin, their wings about ¹/₁₂′ wide, generally persistent on the scale after the seed falls.

A tree, usually 40°—50°, occasionally 80° high, with a short trunk 2°—5° in diameter, stout long-persistent branches ultimately forming a low wide round-topped head, and stout branchlets orange-green and covered at first with soft fine pubescence, usually soon glabrous and darker colored; at high elevations often a low spreading shrub. Bark of young stems and branches thin, smooth, light gray or silvery white, becoming on old trunks 1′—2′ thick, dark brown or nearly black, and divided by deep fissures into broad ridges broken into nearly square plates covered by small closely appressed scales. Wood light, soft, close-grained, pale clear yellow, turning red with exposure; occasionally manufactured into lumber.

Distribution. Eastern slope of the Rocky Mountains from Alberta to western Texas and westward on mountain ranges at elevations of 5000° to 12,000° to Montana, and southern California, reaching the western slopes of the Sierra Nevada at the head of King’s River near the summit of San Gorgonio Mountain and in Snow Cañon, San Bernardino Range; usually scattered singly or in small groves; forming open forests on the eastern foothills of the Rocky Mountains of Montana and on the ranges of central Nevada; attaining its largest size on those of northern New Mexico and Arizona.

5. [Pinus albicaulis] Engelm. White Pine.

Leaves stout, rigid, slightly incurved, dark green, marked by 1—3 rows of dorsal stomata, clustered at the ends of the branches, 1½′—2½′ long, persistent for from five to eight years. Flowers opening in July, scarlet. Fruit ripening in August, oval or subglobose, horizontal, sessile, dark purple, 1½′—3′ long, with scales thickened, acute, often armed with stout pointed umbos, remaining closed at maturity; seeds wingless, acute, subcylindric or flattened on one side, ⅓′—½′ long, ⅓′ thick, with a thick dark chestnut-brown hard shell.

A tree, usually 20°—30° or rarely 60° high, generally with a short trunk 2°—4° in diameter, stout very flexible branches, finally often standing nearly erect and forming an open very irregular broad head, and stout dark red-brown or orange-colored branchlets puberulous for two years or sometimes glabrous; at high elevations often a low shrub, with wide-spreading nearly prostrate stems. Bark thin, except near the base of old trunks and broken by narrow fissures into thin narrow brown or creamy white plate-like scales. Wood light, soft, close-grained, brittle, light brown. The large sweet seeds are gathered and eaten by Indians.

Distribution. Alpine slopes and exposed ridges between 5000° and 12,000° elevation, forming the timber-line on many mountain ranges from latitude 53° north in the Rocky Mountains and British Columbia, southward to the Wind River and Salt River Ranges, Wyoming, the mountains of eastern Washington and Oregon, the Cascade Range, the mountains of northern California and the Sierra Nevada to Mt. Whitney.

6. [Pinus Balfouriana] Balf. Foxtail Pine.

Leaves stout, rigid, dark green and lustrous on the back, pale and marked on the ventral faces by numerous rows of stomata, 1′—1½′ long, persistent for ten or twelve years. Flowers: male dark orange-red; female dark purple. Fruit 3½′—5′ long, with scales armed with minute incurved prickles, dark purple, turning after opening dark red or mahogany color; seeds full and rounded at the apex, compressed at the base, pale, conspicuously mottled with dark purple, ⅓′ long, their wings narrowed and oblique at the apex, about 1′ long and ¼′ wide.

A tree, usually 30°—40° or rarely 90° high, with a trunk generally 1°—2° or rarely 5° in diameter, short stout branches forming an open irregular pyramidal picturesque head, and long rigid more or less spreading puberulous, soon glabrous, dark orange-brown ultimately dark gray-brown or nearly black branchlets, clothed only at the extremities with the long dense brush-like masses of foliage. Bark thin, smooth, and milky white on the stems and branches of young trees, becoming on old trees sometimes ¾′ thick, dark red-brown, deeply divided into broad flat ridges. broken into nearly square plates separating on the surface into small closely appressed scales. Wood light, soft and brittle, pale reddish brown.

Distribution. California, on rocky slopes and ridges, forming scattered groves on Scott Mountain, Siskiyou County, at elevations of 5000°—6000°; on the mountains at the head of the Sacramento River; on Mt. Yolo Bally in the northern Coast Range, and on the southern Sierra Nevada up to elevations of 11,500°, growing here to its largest size and forming an extensive open forest on the Whitney Plateau east of the cañon of Kern River, and at the highest elevations often a low shrub, with wide-spreading prostrate stems.

7. [Pinus aristata] Engelm. Foxtail Pine. Hickory Pine.

Leaves stout or slender, dark green, lustrous on the back, marked by numerous rows of stomata on the ventral faces, 1′—1½′ long, often deciduous at the end of ten or twelve years or persistent four or five years longer. Flowers male dark orange-red; female dark purple. Fruit 3′—3½′ long, with scales armed with slender incurved brittle prickles nearly ¼′ long, dark purple-brown on the exposed parts, the remainder dull red, opening and scattering their seeds about the 1st of October; seeds nearly oval, compressed, light brown mottled with black, ¼′ long, their wings broadest at the middle, about ⅓′ long and ¼′ wide.

A bushy tree, occasionally 40°—50° high, with a short trunk 2°—3° in diameter, short stout branches in regular whorls while young, in old age growing very irregularly, the upper erect and much longer than the usually pendulous lower branches, and stout light orange-colored, glabrous, or at first puberulous, ultimately dark gray-brown or nearly black branchlets clothed at the ends with long compact brush-like tufts of foliage. Bark thin, smooth, milky white on the stems and branches of young trees, becoming on old trees ½′—¾′ thick, red-brown, and irregularly divided into flat connected ridges separating on the surface into small closely appressed scales. Wood light, soft, not strong, light red; occasionally used for the timbers of mines and for fuel.

Distribution. Rocky or gravelly slopes at the upper limit of tree growth and rarely below 8,000° above the sea from the outer range of the Rocky Mountains of Colorado to those of southern Utah, central and southern Nevada, southeastern California, and the San Francisco peaks of northern Arizona.

8. [Pinus cembroides] Zucc. Nut Pine. Piñon.

Leaves in 2 or 3-leaved clusters, slender, much incurved, dark green, sometimes marked by rows of stomata on the 3 faces, 1′—2′ long, deciduous irregularly during their third and fourth years. Flowers: male in short crowded clusters, yellow; female dark red. Fruit subglobose, 1′—2′ broad; seeds subcylindric or obscurely triangular, more or less compressed at the pointed apex, full and rounded at base, nearly black on the lower side and dark chestnut-brown on the upper, ½′—¾′ long, the margin of their outer coat adnate to the cone-scale.

A bushy tree, with a short trunk rarely more than a foot in diameter and a broad round-topped head, usually 15°—20° high, stout spreading branches, and slender dark orange-colored branchlets covered at first with matted pale deciduous hairs, dark brown and sometimes nearly black at the end of five or six years; in sheltered cañons on the mountains of Arizona and in Lower California occasionally 50° or 60° tall. Bark about ½′ thick, irregularly divided by remote shallow fissures and separated on the surface into numerous large thin light red-brown scales. Wood light, soft, close-grained, pale clear yellow. The large oily seeds are an important article of food in northern Mexico, and are sold in large quantities in Mexican towns.

Distribution. Mountain ranges of central and southern Arizona, usually only above elevations of 6500°, often covering their upper slopes with open forests; in an isolated station on the Edwards Plateau on uplands and in cañons at the headwaters of the Frio and Nueces Rivers, Edwards and Kerr Counties, Texas; on the Sierra de Laguna, Lower California, and on many of the mountain ranges of northern Mexico; passing into the following varieties differing only in the number of the leaves in the leaf-clusters, and in their thickness.

Pinus cembroides var. Parryana Voss. Nut Pine. Piñon.

Pinus quadrifolia Sudw.

Leaves in 1—5 usually 4-leaved clusters, stout, incurved, pale glaucous green, marked on the three surfaces by numerous rows of stomata, 1¼′—1½′ long, irregularly deciduous, mostly falling in their third year.

A tree, 30°—40° high, with a short trunk occasionally 18′ in diameter, and thick spreading branches forming a compact regularpyramidal or in old age a low round-topped irregular head, and stout branchlets coated at first with soft pubescence, and light orange-brown. Bark ½′—¾′ thick, dark brown tinged with red, and divided by shallow fissures into broad flat connected ridges covered by thick closely appressed plate-like scales. Wood light, soft, close-grained, pale brown or yellow. The seeds form an important article of food for the Indians of Lower California.

Distribution. Arid mesas and low mountain slopes of Lower California southward to the foothills of the San Pedro Mártir Mountains, extending northward across the boundary of California to the desert slopes of the Santa Rosa Mountains, Riverside County, where it is common at elevations of 5000° above the sea-level.

Pinus cembroides var. edulis Voss. Nut Pine. Piñon.

Pinus edulis Engelm.

Leaves in 2 or rarely in 3-leaved clusters, stout, semiterete or triangular, rigid, incurved, dark-green, marked by numerous rows of stomata, ¾′—1½′ long, deciduous during the third or not until the fourth or fifth year, dropping irregularly and sometimes persistent for eight or nine years.

A tree often 40°—50° high with a tall trunk occasionally 2° in diameter and short erect branches forming a narrow head, or frequently with a short divided trunk and a low round-topped head of spreading branches, and thick branchlets orange color during their first and second years, finally becoming light gray or dark brown sometimes tinged with red. Bark ½′—¾′ thick and irregularly divided into connected ridges covered by small closely appressed light brown scales tinged with red or orange color. Wood light, soft, not strong, brittle, pale brown; largely employed for fuel and fencing, and as charcoal used in smelting; in western Texas occasionally sawed into lumber. The seeds form an important article of food among Indians and Mexicans, and are sold in the markets of Colorado and New Mexico.

Distribution. Eastern foothills of the outer ranges of the Rocky Mountains, from northern Colorado (Owl Cañon, Larimer County); to the extreme western part of Oklahoma (near Kenton, Cimarron County, G. W. Stevens) and to western Texas, westward to eastern Utah, southwestern Wyoming, and to northern and central Arizona; over the mountains of northern Mexico, and on the San Pedro Mártir Mountains, Lower California; often forming extensive open forests at the eastern base of the Rocky Mountains, on the Colorado plateau, and on many mountain ranges of northern and central Arizona up to elevations of 7000° above the sea.

Pinus cembroides var. monophylla Voss. Nut Pine. Piñon.

Pinus monophylla Torr.

Leaves in 1 or 2-leaved clusters, rigid, incurved, pale glaucous green, marked by 18—20 rows of stomata, usually about 1½′ long, sometimes deciduous during their fourth and fifth seasons, but frequently persistent until their twelfth year.

A tree usually 15°—20°, occasionally 40°—50° high, with a short trunk rarely more than a foot in diameter and often divided near the ground into several spreading stems, short thick branches forming while the tree is young a broad rather compact pyramid, and in old age often pendulous and forming a low round-topped often picturesque head, and stout light orange-colored ultimately dark brown branchlets. Bark about ¾′ thick and divided by deep irregular fissures into narrow connected flat ridges broken on the surface into thin closely appressed light or dark brown scales tinged with red or orange color. Wood light, soft, weak, and brittle; largely used for fuel, and charcoal used in smelting. The seeds supply an important article of food to the Indians of Nevada and California.

Distribution. Dry gravelly slopes and mesas from the western base of the Wasatch Mountains of Utah, westward over the mountain ranges of Nevada to the eastern slopes of the southern Sierra Nevada, and to their western slope at the headwaters of the Tuolumne, Kings and Kern Rivers, and southward to northern Arizona and to the mountains of southern California where it is common on the San Bernardino and San Jacinto Mountains between altitudes of 3500° and 7000°, and on the Sierra del Pinal, Lower California; often forming extensive open forests at elevations between 5000° and 7000°.

PITCH PINES.

Wood usually heavy, coarse-grained, generally dark-colored, with pale often thick sapwood; cones green at maturity (sometimes purple in 10 and 21) becoming various shades of brown; cone-scales more or less thickened, mostly armed; seeds shorter than their wings (except in 17 and 28); leaves with 2 fibro-vascular bundles.

Sheaths of the leaf-clusters deciduous; cones ½′—2′ long, maturing in the third year, leaves in 3-leaved clusters, slender, 2½′—4′ long.9. [P. leiophylla] (H). Sheaths of the leaf-clusters persistent. Leaves in 3-leaved clusters (3 and 5-leaved in 10, 3—2 leaved in 12). Cones subterminal, usually deciduous above the basal scales persistent on the branch. Buds brown; leaves in 2—5-leaved clusters.10. [P. ponderosa] (B, F, G, H). Buds white.11. [P. palustris] (C). Cones lateral. Cones symmetrical, their outer scales not excessively developed. Leaves in 2 and 3-leaved clusters, 8′—12′ long; cones short-stalked.12. [P. caribæa] (C). Leaves in 3-leaved clusters; cones sessile. Cones oblong-conic, prickles stout; leaves 6′—9′ long.13. [P. taeda] (A, C). Cones ovoid, prickles slender; leaves 3′—5′ long.14. [P. rigida] (A, C). Cones unsymmetrical by the excessive development of the scales on the outer side. Cones 5′—6′ long, their scales not prolonged into stout, straight or curved spines. Prickles of the cone-scales minute.15. [P. radiata] (G). Prickles of the cone-scales stout.16. [P. attenuata] (G). Cones 6′—14′ long, their scales prolonged into stout, straight or curved spines; leaves long and stout. Cones oblong-ovoid; seeds longer than their wings.17. [P. Sabiniana] (G). Cones oblong-conic; seeds shorter than their wings.18. [P. Coulteri] (G). Leaves in 2-leaved clusters (2 and 3-leaved in 23). Cones subterminal. Cones symmetrical, 2′—2½′ long, their scales unarmed; leaves 5′—6′ long.19. [P. resinosa] (A). Cones unsymmetrical by the greater development of the scales on the outer side, armed with slender prickles; leaves 1′—4′ long.20. [P. contorta] (B, F, G). Cones lateral. Cones about 2′ long. Cone-scales very unevenly developed and mostly unarmed; cones incurved; leaves less than 2′ long.21. [P. Banksiana] (A). Cone-scales evenly developed, armed with weak or deciduous prickles; leaves up to 4′ in length. Bark of the branches and upper trunk smooth.22. [P. glabra] (C). Bark of the branches and upper trunk roughened.23. [P. echinata] (A, C). Cones about 3′ long, armed with persistent spines. Cone-scales armed with slender or stout prickles. Cone-scales evenly developed, their prickles slender, acuminate, from a broad base; leaves 3′ long or less. Cones opening at maturity.24. [P. virginiana] (A, C). Cones often remaining closed for many years.25. [P. clausa] (C). Cone-scales unevenly developed and armed with stout prickles; cones 2′—3½′ long, remaining closed; leaves 4′—6′ long.26. [P. muricata.] Cone-scales armed with very stout hooked spines; cones 2½′—3′ long; opening in the autumn or remaining closed for two or three years; leaves 2′ long or less.27. [P. pungens.] Leaves in 5-leaved clusters; cones 4′—6′ long, unsymmetrical, their scales thick; seeds longer than their wings; leaves stout, 9′—13′ long.28. [P. Torreyana] (G).

9. [Pinus leiophylla] Schlecht. and Cham. Yellow Pine.

Pinus chihuahuana, Engelm.

Leaves slender, pale glaucous green, marked by 6—8 rows of conspicuous stomata on each of the 3 sides, 2½′—4′ long, irregularly deciduous from their fourth season, their sheaths deciduous. Flowers: male yellow; female yellow-green. Fruit ovoid, horizontal or slightly declining, long-stalked, 1½′—2′ long, becoming light chestnut-brown and lustrous, maturing at the end of the third season, with scales only slightly thickened, their ultimately pale umbos armed with recurved deciduous prickles; seeds oval, rounded above and pointed below, about ⅛′ long, with a thin dark brown shell, their wings ⅓′ long and broadest near the middle.

A tree, rarely more than 40°—50° high, with a tall trunk sometimes 2° in diameter, stout slightly ascending branches forming a narrow open pyramidal or round-topped head of thin pale foliage, and slender bright orange-brown branchlets, soon becoming dull red-brown. Bark of old trunks ¾′—1½′ thick, dark reddish brown or sometimes nearly black, and deeply divided into broad flat ridges covered with thin closely appressed scales. Wood light, soft, not strong but durable, light orange color, with thick much lighter colored sapwood. Often forming coppice by the growth of shoots from the stump of cut trees.

Distribution. Mountain ranges of southern New Mexico and Arizona, usually at elevations between 6000° and 7000°; not common; more abundant on the Sierra Madre of northern Mexico and on several of the short ranges of Chihuahua and Sonora, and of a larger size in Mexico than in the United States.

10. [Pinus ponderosa] Laws. Yellow Pine. Bull Pine.

Leaves tufted at the ends of naked branches, in 2 or in 2 and 3-leaved clusters, stout, dark yellow-green, marked by numerous rows of stomata on the 3 faces, 5′—11′ long, mostly deciduous during their third season. Flowers: male yellow; female clustered or in pairs, dark red. Fruit ellipsoidal, horizontal or slightly declining, nearly sessile or short-stalked, 3′—6′ long, often clustered, bright green or purple when fully grown, becoming light reddish brown, with narrow scales much thickened at the apex and armed with slender prickles, mostly falling soon after opening and discharging their seeds, generally leaving the lower scales attached to the peduncle; seeds ovoid, acute, compressed at the apex, full and rounded below, ¼′ long, with a thin dark purple often mottled shell, their wings usually broadest below the middle, gradually narrowed at the oblique apex, 1′—1¼′ long, about 1′ wide.

A tree, sometimes 150°—230° high, with a massive stem 5°—8° in diameter, short thick many-forked often pendulous branches generally turned upward at the ends and forming a regular spire-like head, or in arid regions a broader often round-topped head surmounting a short trunk, and stout orange-colored branchlets frequently becoming nearly black at the end of two or three years. Bark for 80—100 years broken into rounded ridges covered with small closely appressed scales, dark brown, nearly black or light cinnamon-red, on older trees becoming 2′—4′ thick and deeply and irregularly divided into plates sometimes 4°—5° long and 12′—18′ wide, and separating into thick bright cinnamon-red scales. Wood hard, strong, comparatively fine-grained, light red, with nearly white sapwood sometimes composed of more than 200 layers of annual growth; largely manufactured into lumber used for all sorts of construction, for railway-ties, fencing, and fuel.

Distribution. Mountain slopes, dry valleys, and high mesas from northwestern Nebraska and western Texas to the shores of the Pacific Ocean, and from southern British Columbia to Lower California and northern Mexico; extremely variable in different parts of the country in size, in the length and thickness of the leaves, size of the cones, and in the color of the bark. The form of the Rocky Mountains (var. scopulorum, Engelm.), ranging from Nebraska to Texas, and over the mountain ranges of Wyoming, eastern Montana and Colorado, and to northern New Mexico and Arizona, where it forms on the Colorado plateau with the species the most extensive Pine forests of the continent, has nearly black furrowed bark, rigid leaves in clusters of 2 or 3 and 3′—6′ long, and smaller cones, with thin scales armed with slender prickles hooked backward. More distinct is

Pinus ponderosa var. Jeffreyi Vasey.

This tree forms great forests about the sources of the Pitt River in northern California, along the eastern slopes of the central and southern Sierra Nevada, growing often on the most exposed and driest ridges, and in southern California on the San Bernardino and San Jacinto ranges up to elevations of 7000° above the sea, on the Cuyamaca Mountains, and in Lower California on the Sierra del Pinal and the San Pedro Mártir Mountains.

A tree, 100° to nearly 200° high, with a tall massive trunk 4°—6° in diameter, covered with bright cinnamon-red bark deeply divided into large irregular plates, stiffer and more elastic leaves 4′—9′ long and persistent on the glaucous stouter branchlets for six to nine years, yellow-green staminate flowers, short-stalked usually purple cones 5′—15′ long, their scales armed with stouter or slender prickles usually hooked backward, and seeds often nearly ½′ long with larger wings.

Occasionally planted as an ornamental tree in eastern Europe, especially the variety Jeffreyi, which is occasionally successfully cultivated in the eastern states.

Pinus ponderosa var. arizonica Shaw. Yellow Pine.

Pinus arizonica Engelm.

Leaves tufted at the ends of the branches, in 3—5-leaved clusters, stout, rigid, dark green, stomatiferous on their 3 faces, 5′—7′ long, deciduous during their third season. Fruit ovoid, horizontal, 2′—2½′ long, becoming light red-brown, with thin scales much thickened at the apex and armed with slender recurved spines; seeds full and rounded below, slightly compressed towards the apex, ⅛′ long, with a thick shell, their wings broadest above the middle, about ⅓′ long and ¼′ wide.

A tree, 80°—100° high, with a tall straight massive trunk 3°—4° in diameter, thick spreading branches forming a regular open round-topped or narrow pyramidal head, and stout branchlets orange-brown and pruinose when they first appear, becoming dark gray-brown. Bark on young trunks dark brown or almost black and deeply furrowed, becoming on old trees 1½′—2′ thick and divided into large unequally shaped plates separating on the surface into thin closely appressed light cinnamon-red scales. Wood light, soft, not strong, rather brittle, light red or often yellow, with thick lighter yellow or white sapwood; in Arizona occasionally manufactured into coarse lumber.

Distribution. High cool slopes on the sides of cañons of the mountain ranges of southern Arizona at elevations between 6000° and 8000°, sometimes forming nearly pure forests; more abundant and of its largest size on the mountains of Sonora and Chihuahua.

11. [Pinus palustris] Mill. Long-leaved Pine. Southern Pine.

Leaves in crowded clusters, forming dense tufts at the ends of the branches, slender, flexible, pendulous, dark green, 8′—18′ long, deciduous at the end of their second year. Flowers in very early spring before the appearance of the new leaves, male in short dense clusters, dark rose-purple; female just below the apex of the lengthening shoot in pairs or in clusters of 3 or 4, dark purple. Fruit cylindric-ovoid, slightly curved, nearly sessile, horizontal or pendant, 6′—10′ long, with thin flat scales rounded at apex and armed with small reflexed prickles, becoming dull brown; in falling leaving a few of the basal scales attached to the stem; seeds almost triangular, full and rounded on the sides, prominently ridged, about ½′ long, with a thin pale shell marked with dark blotches on the upper side, and wings widest near the middle, gradually narrowed to a very oblique apex, about 1¾′ long and ⁷/₁₆′ wide.

A tree, 100°—120° high, with a tall straight slightly tapering trunk usually 2°—2½° or occasionally 3° in diameter, stout slightly branched gnarled and twisted limbs covered with thin dark scaly bark and forming an open elongated and usually very irregular head one third to one half the length of the tree, thick orange-brown branchlets, and acute winter-buds covered by elongated silvery white lustrous scales divided into long spreading filaments forming a cobweb-like network over the bud. Bark of the trunk ¹/₁₆′—½′ thick, light orange-brown, separating on the surface into large closely appressed papery scales. Wood heavy, exceedingly hard, strong, tough, coarse-grained, durable, light red to orange color, with very thin nearly white sapwood; largely used as “southern pine” or “Georgia pine” for masts and spars, bridges, viaducts, railway-ties, fencing, flooring, the interior finish of buildings, the construction of railway-cars, and for fuel and charcoal. A large part of the naval stores of the world is produced from this tree, which is exceedingly rich in resinous secretions.

Distribution. Generally confined to a belt of late tertiary sands and gravels stretching along the coast of the Atlantic and Gulf states and rarely more than 125 miles wide, from southeastern Virginia to the shores of Indian River and the valley of the Caloosahatchee River, Florida, and along the Gulf coast to the uplands east of the Mississippi River, extending northward in Alabama to the southern foothills of the Appalachian Mountains and to central and western Mississippi (Hinds and Adams Counties); west of the Mississippi River to the valley of the Trinity River, Texas, and through eastern Texas and western Louisiana nearly to the northern borders of this state.

12. [Pinus caribæa] Morelet. Slash Pine. Swamp Pine.

Pinus heterophylla Sudw.

Leaves stout, in crowded 2 and 3-leaved clusters, dark green and lustrous, marked by numerous bands of stomata on each face, 8′—12′ long, deciduous at the end of their second season. Flowers in January and February before the appearance of the new leaves, male in short crowded clusters, dark purple; female lateral on long peduncles, pink. Fruit ovoid or ovoid-conic, reflexed during its first year, pendant, 2′—6′ long, with thin flexible flat scales armed with minute incurved or recurved prickles, becoming dark rich lustrous brown; seeds almost triangular, full and rounded on the sides, 1⅙′—1¼′ long, with a thin brittle dark gray shell mottled with black, and dark brown wings ¾′—1′ long, ¼′ wide, their thickened bases encircling the seeds and often covering a large part of their lower surface.

A tree, often 100° high, with a tall tapering trunk 2½°—3° in diameter, heavy horizontal branches forming a handsome round-topped head, and stout orange-colored ultimately dark branchlets. Bark ¾′—½′ thick, and separating freely on the surface into large thin scales. Wood heavy, exceedingly hard, very strong, durable, coarse-grained, rich dark orange color, with thick nearly white sapwood; manufactured into lumber and used for construction and railway-ties. Naval stores are largely produced from this tree.

Distribution. Coast region of South Carolina southward over the coast plain to the keys of southern Florida and along the Gulf coast to eastern Louisiana (Saint Tammany, Washington, southern Tangipahoa and eastern Livingston Parishes); common on the Bahamas, on the Isle of Pines, and on the lowlands of Honduras and eastern Guatemala; in the coast region of the southern states gradually replacing the Long-leaved Pine, Pinus palustris, Mill.

13. [Pinus tæda] L. Loblolly Pine. Old Field Pine.

Leaves slender, stiff, slightly twisted, pale green and somewhat glaucous, 6′—9′ long, marked by 10—12 rows of large stomata on each face, deciduous during their third year. Flowers opening from the middle of March to the first of May; male crowded in short spikes, yellow; female lateral below the apex of the growing shoot, solitary or clustered, short-stalked, yellow. Fruit oblong-conic to ovoid-cylindric, nearly sessile, 2′—6′ long, becoming light reddish brown, with thin scales rounded at the apex and armed with short stout straight or reflexed prickles, opening irregularly and discharging their seeds during the autumn and winter, and usually persistent on the branches for another year; seeds rhomboidal, full and rounded, ¼′ long, with a thin dark brown rough shell blotched with black, and produced into broad thin lateral margins, encircled to the base by the narrow border of their thin pale brown lustrous wing broadest above the middle, 1′ long, about ¼′ wide.

A tree, generally 80°—100° high, with a tall straight trunk usually about 2° but occasionally 5° in diameter, short thick much divided branches, the lower spreading, the upper ascending and forming a compact round-topped head, and comparatively slender glabrous branchlets brown tinged with yellow during their first season and gradually growing darker in their second year. Bark of the trunk ¾′—1½′ thick, bright red-brown, and irregularly divided by shallow fissures into broad flat ridges covered with large thin closely appressed scales. Wood weak, brittle, coarse-grained, not durable, light brown, with orange-colored or often nearly white sapwood, often composing nearly half the trunk; largely manufactured into lumber, used for construction and the interior finish of buildings.

Distribution. Cape May, New Jersey, through southern Delaware and eastern Maryland and southward to the shores of Indian River and Tampa Bay, Florida, westward to middle North Carolina and through South Carolina and Georgia and the eastern Gulf states to the Mississippi River, extending into southern Tennessee and northeastern Mississippi; west of the Mississippi River from southern Arkansas and the southwestern part of Oklahoma through western Louisiana to the shores of the Gulf of Mexico, and through eastern Texas to the valley of the Colorado River; on the Atlantic coast often springing up on lands exhausted by agriculture; west of the Mississippi River one of the most important timber-trees, frequently growing in nearly pure forests on rolling uplands.

14. [Pinus rigida] Mill. Pitch Pine.

Leaves stout, rigid, dark yellow-green, marked on the 3 faces by many rows of stomata, 3′—5′ long, standing stiffly and at right angles with the branch, deciduous during their second year. Flowers: male in short crowded spikes, yellow or rarely purple; female often clustered and raised on short stout stems, light green more or less tinged with rose color. Fruit ovoid, acute at apex, nearly sessile, often clustered, 1′—3½′ long, becoming light brown, with thin flat scales armed with recurved rigid prickles, often remaining on the branches for ten or twelve years; seeds nearly triangular, full and rounded on the sides, ¼′ long, with a thin dark brown mottled roughened shell and wings broadest below the middle, gradually narrowed to the very oblique apex, ¾′ long, ⅓′ wide.

A tree, 50°—60° or rarely 100° high, with a short trunk occasionally 3° in diameter, thick contorted often pendulous branches covered with thick much roughened bark, forming a round-topped thick head, often irregular and picturesque, and stout bright green branchlets becoming dull orange color during their first winter and dark gray-brown at the end of four or five years; often fruitful when only a few feet high. Bark of young stems thin and broken into plate-like dark red-brown scales, becoming on old trunks ¾′—1½′ thick, deeply and irregularly fissured, and divided into broad flat connected ridges separating on the surface into thick dark red-brown scales often tinged with purple. Wood light, soft, not strong, brittle, coarse-grained, very durable, light brown or red, with thick yellow or often white sapwood; largely used for fuel and in the manufacture of charcoal; occasionally sawed into lumber.

Distribution. Sandy plains and dry gravelly uplands, or less frequently in cold deep swamps; island of Mt. Desert, Maine, to the northern shores of Lake Ontario, and southward to southern Delaware and southern Ohio (Scioto County) and along the Appalachian Mountains to northern Georgia and to their western foothills in West Virginia, Kentucky, and Tennessee; very abundant in the coast region south of Massachusetts; sometimes forming pure forests in New Jersey and Pennsylvania.

Pinus rigida var. serotina Loud. Pond Pine. Marsh Pine.

Pinus serotina Michx.

Leaves in clusters of 3 or occasionally of 4, slender, flexuose, dark yellow-green, 6′—8′ long, marked by numerous rows of stomata on the 3 faces, deciduous during their third and fourth years. Flowers: male in crowded spikes, dark orange color; female clustered or in pairs on stout stems. Fruit subglobose to ovoid, full and rounded or pointed at apex, subsessile or short-stalked, horizontal or slightly declining, 2′—2½′ long, with thin nearly flat scales armed with slender incurved mostly deciduous prickles, becoming light yellow-brown at maturity, often remaining closed for one or two years and after opening long-persistent on the branches; seeds nearly triangular, often ridged below, full and rounded at the sides, ⅛′ long, with a thin nearly black roughened shell produced into a wide border, the wings broadest at the middle, gradually narrowed at the ends, ¾′ long, ¼′ wide.

A tree, usually 40°—50° or occasionally 70°—80° high, with a short trunk sometimes 3° but generally not more than 2° in diameter, stout often contorted branches more or less pendulous at the extremities, forming an open round-topped head, and slender branchlets dark green when they first appear, becoming dark orange color during their first winter and dark brown or often nearly black at the end of four or five years. Bark of the trunk ½′—¾′ thick, dark red-brown and irregularly divided by narrow shallow fissures into small plates separating on the surface into thin closely appressed scales. Wood very resinous, heavy, soft, brittle, coarse-grained, dark orange color, with thick pale yellow sapwood; occasionally manufactured into lumber.

Distribution. Low wet flats or sandy or peaty swamps; near Cape May, New Jersey, and southeastern Virginia southward near the coast to northern Florida and central Alabama.

15. [Pinus radiata] D. Don. Monterey Pine.

Leaves in 3, rarely in 2-leaved clusters, slender, bright rich green, 4′—6′ long, mostly deciduous during their third season. Flowers: male in dense spikes, yellow; female clustered, dark purple. Fruit ovoid, pointed at apex, very oblique at base, short-stalked, reflexed, 3′—7′ long, becoming deep chestnut-brown and lustrous, with scales much thickened and mammillate toward the base on the outer side of the cone, thinner on the inner side and at its apex, and armed with minute thickened incurved or straight prickles, long-persistent and often remaining closed on the branches for many years; seeds ellipsoidal, compressed, ¼′ long, with a thin brittle rough nearly black shell, their wings light brown, longitudinally striped, broadest above the middle, gradually narrowed and oblique at apex, 1′ long, ¼′ wide.

A tree, usually 40°—60° rarely 100°—115° high, with a tall trunk usually 1°—2° but occasionally 4½° in diameter, spreading branches forming a regular narrow open round-topped head, and slender branchlets light or dark orange color, at first often covered with a glaucous bloom, ultimately dark red-brown. Bark of the trunk 1½′—2′ thick, dark red-brown, and deeply divided into broad flat ridges broken on the surface into thick appressed plate-like scales. Wood light, soft, not strong, brittle, close-grained; occasionally used as fuel.

Distribution. In a narrow belt a few miles wide on the California coast from Pescadero to the shores of San Simeon Bay; in San Luis Obispo County near the village of Cambria; on the islands of Santa Rosa and Santa Cruz of the Santa Barbara group; and on Guadaloupe Island off the coast of Lower California; most abundant and of its largest size on Point Pinos south of the Bay of Monterey, California.

Largely planted for the decoration of parks in western and southern Europe, occasionally planted in the southeastern states and in Mexico, Australia, New Zealand, and other regions with temperate climates, and more generally in the coast region of the Pacific states from Vancouver Island southward than any other Pine-tree.

16. [Pinus attenuata] Lemm. Knob-cone Pine.

Leaves slender, firm and rigid, pale yellow or bluish green, marked by numerous rows of stomata on their 3 faces, 3′—7′, usually 4′—5′ long. Flowers: male orange-brown; female fascicled, often with several fascicles on the shoot of the year. Fruit elongated, conic, pointed, very oblique at base by the greater development of the scales on the outer side, whorled, short-stalked, strongly reflexed and incurved, 3′—6′ long, becoming light yellow-brown, with thin flat scales rounded at apex, those on the outer side being enlarged into prominent transversely flattened knobs armed with thick flattened incurved spines, those on the inner side of the cone slightly thickened and armed with minute recurved prickles, persistent on the stems and branches for thirty or forty years, sometimes becoming completely imbedded in the bark of old trunks, and usually not opening until the death of the tree; seeds ellipsoidal, compressed, acute at apex, ¼′ long, with a thin oblique shell, their wings broadest at the middle, gradually narrowed to the ends, 1¼′ long, ⅓′ wide.

A tree, usually about 20° high, with a trunk a foot in diameter, and often fruitful when only 4° or 5° tall; occasionally growing to the height of 80°—100°, with a trunk 2½° thick, and frequently divided above the middle into two ascending stems, slender branches arrangedin regular whorls while the tree is young, and in old age forming a narrow round-topped straggling head of sparse thin foliage, and slender dark orange-brown branchlets growing darker during their second season. Bark of young stems and branches thin, smooth, pale brown, becoming at the base of old trunks ¼′—½′ thick and dark brown often tinged with purple, slightly and irregularly divided by shallow fissures and broken into large loose scales. Wood light, soft, not strong, brittle, coarse-grained, light brown, with thick sapwood sometimes slightly tinged with red.

Distribution. Dry mountain slopes from the valley of the Mackenzie River in Oregon over the mountains of southwestern Oregon, where it is most abundant and grows to its largest size, often forming pure forests over large areas, southward along the western slopes of the Cascade Mountains; in California on the northern cross ranges, the coast ranges from Trinity to Sonoma Counties, the western slopes of the Sierra Nevada to Mariposa County, and over the southern coast ranges from Santa Cruz to the dry arid southern slopes of the San Bernardino Mountains, where it forms a belt between City and East Twin Creeks at an altitude of 3500° above the sea.

17. [Pinus Sabiniana] Dougl. Digger Pine. Bull Pine.

Leaves stout, flexible, pendant, pale blue-green, marked on each face with numerous rows of pale stomata, 8′—12′ long, deciduous usually in their third and fourth years. Flowers: male yellow; female on stout peduncles, dark purple. Fruit oblong-ovoid, full and rounded at base, pointed, becoming light reddish brown, 6′—10′ long, long-stalked, pendulous, the scales narrowed into a stout incurved sharp hook, strongly reflexed toward the base of the cone and armed with spur-like incurved spines; seeds full and rounded below, somewhat compressed toward the apex, ¾′ long, ⅓′ wide, dark brown or nearly black, with a thick hard shell, encircled by their wings much thickened on the inner rim, obliquely rounded at the broad apex and about ½ length of nuts.

A tree, usually 40°—50° but occasionally 80° high, with a trunk 3°—4° in diameter, divided generally 15°—20° above the ground into 3 or 4 thick secondary stems, clothed with short crooked branches pendant below and ascending toward the summit of the tree, and forming an open round-topped head remarkable for the sparseness of its foliage, and stout pale glaucous branchlets, becoming dark brown or nearly black during their second season. Bark of the trunk 1½′—2′ thick, dark brown slightly tinged with red or nearly black and deeply and irregularly divided into thick connected ridges covered with small closely appressed scales. Wood light, soft, not strong, close-grained, brittle, light brown or red with thick nearly white sapwood. Abietine, a nearly colorless aromatic liquid with the odor of oil of oranges, is obtained by distilling the resinous juices. The large sweet slightly resinous seeds formed an important article of food for the Indians of California.

Distribution. Scattered singly or in small groups over the dry foothills of western California, ranging from 500° up to 4000° above the sea-level and from the southern slopes of the northern cross ranges to the Tehachapi Mountains and the Sierra de la Liebre; most abundant and attaining its largest size on the eastern foothills of the Sierra Nevada near the centre of the state at elevations of about 2000°; here often the most conspicuous feature of the vegetation.

18. [Pinus Coulteri] D. Don. Pitch Pine.

Leaves tufted at the ends of the branches, stout, rigid, dark blue-green, marked by numerous bands of stomata on the 3 faces, 6′—12′ long, deciduous during their third and fourth seasons. Flowers: male yellow; female dark reddish brown. Fruit oblong-conic, short-stalked and pendant, 10′—14′ long, becoming light yellow-brown, with thick broad scales terminating in a broad, flat, incurved, hooked claw ½′—1½′ long, gradually opening in the autumn and often persistent on the branches for several years; seeds ellipsoidal, compressed, ½′ long, ¼′—⅓′ wide, dark chestnut-brown, with a thick shell, inclosed by their wings, broadest above the middle, oblique at apex, nearly 1′ longer than the seed, about ⅝′ wide.

A tree, 40°—90° high, with a trunk 1°—2½° in diameter, thick branches covered with dark scaly bark, long and mostly pendulous below, short and ascending above, and forming a loose unsymmetrical often picturesque head, and very stout branchlets dark orange-brown at first, becoming sometimes nearly black at the end of three or four years. Bark of the trunk 1½′—2′ thick, dark brown or nearly black and deeply divided into broad rounded connected ridges covered with thin closely appressed scales. Wood light, soft, not strong, brittle, coarse-grained, light red, with thick nearly white sapwood; occasionally used for fuel. The seeds were formerly gathered in large quantities and eaten by the Indians of southern California.

Distribution. Scattered singly or in small groves through coniferous forests on the dry slopes and ridges of the coast ranges of California at elevations of 3000°—6000° above the sea, from Mount Diablo and the Santa Lucia Mountains to the San Bernardino and Cuyamaca Mountains; and on the Sierra del Pinal, Lower California; most abundant on the San Bernardino and San Jacinto ranges at elevations of about 5000°.

19. [Pinus resinosa] Ait. Red Pine. Norway Pine.

Leaves slender, soft and flexible, dark green and lustrous, 5′—6′ long, obscurely marked on the ventral faces by bands of minute stomata, deciduous during their fourth and fifth seasons. Flowers: male in dense spikes, dark purple; female terminal, short-stalked, scarlet. Fruit ovoid-conic, subsessile, 2′—2¼′ long, with thin slightly concave scales, unarmed, becoming light chestnut-brown and lustrous at maturity; shedding their seeds early in the autumn and mostly persistent on the branches until the following summer; seeds oval, compressed, ⅛′ long, with a thin dark chestnut-brown more or less mottled shell and wings broadest below the middle, oblique at apex, ¾′ long, ¼′—⅓′ broad.

A tree, usually 70°—80° or occasionally 120° high, with a tall straight trunk 2°—3° or rarely 5° in diameter, thick spreading more or less pendulous branches clothing the young stems to the ground and forming a broad irregular pyramid, and in old age an open round-topped picturesque head, and stout branchlets at first orange color, finally becoming light reddish brown. Bark of the trunk ¾′—1¼′ thick and slightly divided by shallow fissures into broad flat ridges covered by thin loose light red-brown scales. Wood light, hard, very close-grained, pale red, with thin yellow often nearly white sapwood; largely used in the construction of bridges and buildings, for piles, masts, and spars. The bark is occasionally used for tanning leather.

Distribution. Light sandy loam or dry rocky ridges, usually forming groves rarely more than a few hundred acres in extent and scattered through forests of other Pines and deciduous-leaved trees; occasionally on sandy flats forming pure forests; Nova Scotia to Lake St. John, westward through Quebec and central Ontario to the valley of the Winnipeg River, and southward to eastern Massachusetts, the mountains of northern Pennsylvania, and to central and southwestern (Port Huron) Michigan, Wisconsin, and Minnesota, most abundant, and growing to its largest size in the northern parts of these states; rare and local in eastern Massachusetts and southward.

Often planted for the decoration of parks, and the most desirable as an ornamental tree of the Pitch Pines which flourish in the northern states.

20. [Pinus contorta] Loud. Scrub Pine.

Leaves dark green, slender, 1′—1½′ long, marked by 6—10 rows of stomata on each face, mostly persistent 4—6 years. Flowers orange-red: male in short crowded spikes; female clustered or in pairs on stout stalks. Fruit ovoid to subcylindric, usually very oblique at base, horizontal or declining, often clustered, ¾′—2′ long, with thin slightly concave scales armed with long slender more or less recurved often deciduous prickles, and toward the base of the cone especially on the upper side developed into thick mammillate knobs, becoming light yellow-brown and lustrous, sometimes opening and losing their seeds as soon as ripe, or remaining closed on the branches and preserving the vitality of their seeds for many years; seeds oblique at apex, acute below, about ⅙′ long, with a thin brittle dark red-brown shell mottled with black and wings widest above the base, gradually tapering toward the oblique apex, ½′ long.

A tree, sometimes fertile when only a few inches high, usually 15°—20° or occasionally 30° tall, with a short trunk rarely more than 18′ in diameter, comparatively thick branches forming a round-topped compact and symmetrical or an open picturesque head, and stout branchlets light orange color when they first appear, finally becoming dark red-brown or occasionally almost black. Bark of the trunk ¾′—1′ thick, deeply and irregularly divided by vertical and cross fissures into small oblong plates covered with closely appressed dark red-brown scales tinged with purple or orange color. Wood light, hard, strong although brittle, coarse-grained, light brown tinged with red, with thick nearly white sapwood; occasionally used for fuel.

Distribution. Coast of Alaska, usually in sphagnum-covered bogs southward in the immediate neighborhood of the coast to the valley of the Albion River, Mendocino County, California; south of the northern boundary of the United States generally inhabiting sand dunes and barrens or occasionally near the shores of Puget Sound the margins of tide pools and deep wet swamps; spreading inland and ascending the coast ranges and western slopes of the Cascade Mountains, where it is not common and where it gradually changes its habit and appearance, the thick deeply furrowed bark of the coast form being found only near the ground, while the bark higher on the stems is thin, light-colored, and inclined to separate into scales, and the leaves are often longer and broader. This is

Pinus contorta var. latifolia S. Wats. Lodge-pole Pine.

Pinus contorta var. Murrayana Engelm.

Leaves yellow-green, usually about 2′ long, although varying from 1′—3′ in length and from ¹/₁₆′ to nearly ⅛′ in width. Fruit occasionally opening as soon as ripe but usually remaining closed and preserving the vitality of the seeds sometimes for twenty years.

A tree, usually 70°—80° but often 150° high, with a trunk generally 2°—3° but occasionally 5°—6° in diameter, slender much-forked branches frequently persistent nearly to the base of the stem, light orange-colored during their early years, somewhat pendulous below, ascending near the top of the tree, and forming a narrow pyramidal spire-topped head. Bark of the trunk rarely more than ¼′ thick, close and firm, light orange-brown and covered by small thin loosely appressed scales. Wood light, soft, not strong, close, straight-grained and easily worked, not durable, light yellow or nearly white, with thin lighter colored sapwood; occasionally manufactured into lumber; also used for railway-ties, mine-timbers, and for fuel.

Distribution. Common on the Yukon hills in the valley of the Yukon River; on the interior plateau of northern British Columbia and eastward to the eastern foothills of the Rocky Mountains, covering with dense forests great areas in the basin of the Columbia River; forming forests on both slopes of the Rocky Mountains of Montana; on the Yellowstone plateau at elevations of 7000°-8000°; common on the mountains of Wyoming, and extending southward to southern Colorado; the most abundant coniferous tree of the northern Rocky Mountain region; common on the ranges of eastern Washington and Oregon, on the mountains of northern California, and southward along the Sierra Nevada, where it attains its greatest size and beauty in alpine forests at elevations between 8000° and 9500°; in southern California the principal tree at elevations between 7000° and 10,000° on the high peaks of the San Bernardino and San Jacinto Mountains; on the upper slopes of the San Pedro Mártir Mountains, Lower California.

21. [Pinus Banksiana] Lamb. Gray Pine. Jack Pine.

Pinus divaricata Du Mont de Cours.

Leaves in remote clusters, stout, flat or slightly concave on the inner face, at first light yellow-green, soon becoming dark green, ¾′—1¼′ long, gradually and irregularly deciduous in their second or third year. Flowers: male in short crowded clusters, yellow; female clustered, dark purple, often with 2 clusters produced on the same shoot. Fruit oblong-conic, acute, oblique at base, sessile, usually erect and strongly incurved, 1½′—2′ long, dull purple or green when fully grown, becoming light yellow and lustrous, with thin stiff scales often irregularly developed, and armed with minute incurved often deciduous prickles; seeds nearly triangular, full and rounded on the sides, ¹/₁₂′ long, with an almost black roughened shell and wings broadest at the middle, full and rounded at apex, ⅓′ long, ⅛′ wide.

A tree, frequently 70° high, with a straight trunk sometimes free of branches for 20°—30° and rarely exceeding 2° in diameter, long spreading branches forming an open symmetrical head, and slender tough flexible pale yellow-green branchlets turning dark purple during their first winter and darker the following year; often not more than 20°—30° tall, with a stem 10′—12′ in diameter; generally fruiting when only a few years old; sometimes shrubby with several low slender stems. Bark of the trunk thin, dark brown slightly tinged with red, very irregularly divided into narrow rounded connected ridges separating on the surface into small thick closely appressed scales. Wood light, soft, not strong, close-grained, clear pale brown or rarely orange color, with thick nearly white sapwood; used for fuel and occasionally for railway-ties and posts; occasionally manufactured into lumber.

Distribution. From Nova Scotia to the valley of the Athabasca River and down the Mackenzie to about latitude 65° north, ranging southward to the coast of Maine, northern New Hampshire and Vermont, the Island of Nantucket (Wauwinet, J. W. Harshburger), northern New York, the shores of Saginaw Bay, Michigan, the southern shores of Lake Michigan in Illinois, the valley of the Wisconsin River, Wisconsin, and central and southeastern Minnesota (with isolated groves in Root River valley, near Rushford, Fillmore County); abundant in central Michigan, covering tracts of barren lands; common and of large size in the region north of Lake Superior; most abundant and of its greatest size west of Lake Winnipeg and north of the Saskatchewan, here often spreading over great areas of sandy sterile soil.

22. [Pinus glabra] Walt. Spruce Pine. Cedar Pine.

Leaves soft, slender, dark green, 1½′—3′ long, marked by numerous rows of stomata, deciduous at the end of their second and in the spring of their third year. Flowers: male in short crowded clusters, yellow; female raised on slender slightly ascending peduncles. Fruit single or in clusters of 2 or 3, reflexed on short stout stalks, subglobose to oblong-ovoid, ½′—2′ long, becoming reddish brown and rather lustrous, with thin slightly concave scales armed with minute straight or incurved usually deciduous prickles; seeds nearly triangular, full and rounded on the sides, ⅛′ long, with a thin dark gray shell mottled with black and wings broadest below the middle, ⅝′ long, ¼′ wide.

A tree, usually 80°—100° or occasionally 120° high, with a trunk 2°—2½° or rarely 3½° in diameter, comparatively small horizontal branches, and slender flexible branchlets at first light red more or less tinged with purple, ultimately dark reddish brown. Bark of young trees and upper trunks smooth pale gray becoming on old stems ½′—¾′ thick, slightly and irregularly divided by shallow fissures into flat connected ridges. Wood light, soft, not strong, brittle, close-grained, light brown, with thick nearly white sapwood; occasionally used for fuel and rarely manufactured into lumber.

Distribution. Valley of the lower Santee River, South Carolina to middle and northwestern Florida; banks of the Alabama River, Dallas County, Alabama; eastern and southwestern Mississippi, and sandy banks of streams in northeastern Louisiana; usually growing singly or in small groves; attaining its largest size and often occupying areas of considerable extent in northwestern Florida.

23. [Pinus echinata] Mill. Yellow Pine. Short-leaved Pine.

Leaves in clusters of 2 and of 3, slender, flexible, dark blue-green, 3′—5′ long, beginning to fall at the end of their second season and dropping irregularly until their fifth year. Flowers: male in short crowded clusters, pale purple; female in clusters of 2 or 3 on stout ascending stems, pale rose color. Fruit ovoid to oblong-conic, subsessile and nearly horizontal or short-stalked and pendant, generally clustered, 1½′—2½′ long, becoming dull brown, with thin scales nearly flat below and rounded at the apex, armed with short straight or somewhat recurved frequently deciduous prickles; seeds nearly triangular, full and rounded on the sides, about ³/₁₆′ long, with a thin pale brown hard shell conspicuously mottled with black, their wings broadest near the middle, ½′ long, ⅛′ wide.

A tree, usually 80°—100° occasionally 120° high, with a tall slightly tapering trunk 3°—4° in diameter, a short pyramidal truncate head of comparatively slender branches, and stout brittle pale green or violet-colored branchlets covered at first with a glaucous bloom, becoming dark red-brown tinged with purple before the end of the first season, their bark beginning in the third year to separate into large scales. Bark of the trunk ¾′—1′ thick and broken into large irregularly shaped plates covered with small closely appressed light cinnamon-red scales. Wood very variable in quality, and in the thickness of the nearly white sapwood, heavy, hard, strong and usually coarse-grained, orange-colored or yellow-brown; largely manufactured into lumber.

Distribution. Long Island (near Northport), and Staten Island, New York, and southern Pennsylvania to northern Florida, and westward through the Gulf states to eastern Texas, through Arkansas to southwestern Oklahoma (near Page, Leflore County, G. W. Stevens) and to southern Missouri and southwestern Illinois and to eastern Tennessee and western West Virginia; most abundant and of its largest size west of the Mississippi River.

24. [Pinus virginiana] Mill. Jersey Pine. Scrub Pine.

Leaves in remote clusters, stout, gray-green, 1½′—3′ long, marked by many rows of minute stomata, gradually and irregularly deciduous during their third and fourth years. Flowers: male in crowded clusters, orange-brown; female on opposite spreading peduncles near the middle of the shoots of the year, generally a little below and alternate with 1 or 2 lateral branchlets, pale green, 2′—3′ long, the scale-tips tinged with rose color. Fruit ovoid-conic, often reflexed, dark red-brown and lustrous, with thin nearly flat scales, and stout or slender persistent prickles, opening in the autumn and slowly shedding their seeds, turning dark reddish brown and remaining on the branches for three or four years; seeds nearly oval, full and rounded, ¼′ long, with a thin pale brown rough shell, their wings broadest at the middle, ⅓′ long, about ⅛′ wide.

A tree, usually 30°—40° high, with a short trunk rarely more than 18′ in diameter, long horizontal or pendulous branches in remote whorls forming a broad open often flat-topped pyramid, and slender tough flexible branchlets at first pale green or green tinged with purple and covered with a glaucous bloom, becoming purple and later light gray-brown; toward the western limits of its range a tree frequently 100° tall, with a trunk 2½°—3° in diameter. Bark of the trunk ¼′—½′ thick, broken by shallow fissures into flat plate-like scales separating on the surface into thin closely appressed dark brown scales tinged with red. Wood light, soft, not strong, brittle, coarse-grained, durable in contact with the soil, light orange color, with thick nearly white sapwood; often used for fuel and occasionally manufactured into lumber.

Distribution. Middle and southern New Jersey; Plymouth, Luzerne County, and central, southern and western Pennsylvania to Columbia County, Georgia, Dallas County, Alabama (near Selma, T. G. Harbison), and to the hills of northeastern Mississippi (Bear Creek near its junction with the Tennessee River, E. N. Lowe), through eastern and middle Tennessee to western Kentucky and to southeastern and southern (Scioto County) Ohio, and southern Indiana; usually small in the Atlantic states and only on light sandy soil, spreading rapidly over exhausted fields; of its largest size west of the Alleghany Mountains on the low hills of southern Indiana.

25. [Pinus clausa] Sarg. Sand Pine. Spruce Pine.

Leaves slender, flexible, dark green, 2′—3½′ long, marked by 10—20 rows of stomata, deciduous during their third and fourth years. Flowers: male in short crowded spikes, dark orange color; female lateral on stout peduncles. Fruit elongated ovoid-conic, often oblique at base, usually clustered and reflexed, 2′—3½′ long, nearly sessile or short-stalked, with convex scales armed with short stout straight or recurved prickles, becoming dark yellow-brown in autumn; some of the cones opening at once, others remaining closed for three or four years before liberating their seeds, ultimately turning to an ashy gray color; others still unopened becoming enveloped in the growing tissues of the stem and branches and finally entirely covered by them; seeds nearly triangular, compressed, ¼′ long, with a black slightly roughened shell, their wings widest near or below the middle, ¾′ long, about ¼′ wide.

A tree, usually 15°—20° high, with a stem rarely a foot in diameter, generally clothed to the ground with wide-spreading branches forming a bushy flat-topped head, and slender tough flexible branchlets, pale yellow-green when they first appear, becoming light orange-brown and ultimately ashy gray; occasionally growing to the height of 70°—80° with a trunk 2° in diameter. Bark on the lower part of the trunk ⅓′—½′ thick, deeply divided by narrow fissures into irregularly shaped generally oblong plates separating on the surface into thin closely appressed bright red-brown scales; on the upper part of the trunk and on the branches thin, smooth, ashy gray. Wood light, soft, not strong, brittle, light orange color or yellow, with thick nearly white sapwood; occasionally used for the masts of small vessels.

Distribution. Coast of the Gulf of Mexico from southern Alabama to Peace Creek, western Florida; eastern Florida from the neighborhood of St. Augustine to New River, Dade County, covering sandy wind-swept plains near the coast; growing to its largest size and most abundant in the interior of the peninsula (Lake and Orange Counties).

26. [Pinus muricata] D. Don. Prickle-cone Pine.

Leaves in crowded clusters, thick, rigid, dark yellow-green, 4′—6′ long, beginning to fall in their second year. Flowers: male in elongated spikes, orange-colored; female short-stalked, whorled, 2 whorls often being produced on the shoot of the year. Fruit ovoid, oblique at base, sessile, in clusters of 3—5 or sometimes of 7, 2′—3½′ but usually about 3′ long, becoming light chestnut-brown and lustrous, with scales much thickened on the outside of the cone, those toward its base produced into stout incurved knobs sometimes armed with stout flattened spur-like often incurved spines, and on the inside of the cone slightly flattened and armed with stout or slender straight prickles; often remaining closed for several years and usually persistent on the stem and branches during the entire life of the tree without becoming imbedded in the wood; seeds nearly triangular, ¼′ long, with a thin nearly black roughened shell, their wings broadest above the middle, oblique at apex, nearly 1′ long, ⅛′ wide.

A tree, usually 40°—50° but occasionally 90° high, with a trunk 2°—3° in diameter, thick spreading branches covered with dark scaly bark, in youth forming a regular pyramid, and at maturity a handsome compact round-topped head of dense tufted foliage, and stout branchlets dark orange-green at first, turning orange-brown more or less tinged with purple. Bark of the lower part of the trunk often 4′—6′ thick and deeply divided into long narrow rounded ridges roughened by closely appressed dark purplish brown scales. Wood light, very strong, hard, rather coarse-grained, light brown, with thick nearly white sapwood; occasionally manufactured into lumber.

Distribution. California coast region from Mendocino County southward, usually in widely separated localities to Point Reyes Peninsula, north of the Bay of San Francisco, and from Monterey to Coon Creek, San Luis Obispo County; in Lower California on Cedros Island and on the west coast between Ensenada and San Quentin; of its largest size and the common Pine-tree on the coast of Mendocino County.

27. [Pinus pungens] Lamb. Table Mountain Pine. Hickory Pine.

Leaves in crowded clusters, rigid, usually twisted, dark blue-green, 1¼′—2½′ long, deciduous during their second and third years. Flowers: male in elongated loose spikes, yellow; female clustered, long-stalked. Fruit ovoid-conic, oblique at base by the greater development of the scales on the outer than on the inner side, sessile, reflexed, in clusters usually of 3 or 4, or rarely of 7 or 8, 2′—3½′ long, becoming light brown and lustrous, with thin tough scales armed with stout hooked curved spines produced from much thickened mammillate knobs, opening as soon as ripe and gradually shedding their seeds, or often remaining closed for two or three years longer, and frequently persistent on the branches for eighteen or twenty years; seeds almost triangular, full and rounded on the sides, nearly ¼′ long, with a thin conspicuously roughened light brown shell, their wings widest below the middle, gradually narrowed to the ends, 1′ long, ¼′ wide.

A tree, when crowded in the forest occasionally 60° high, with a trunk 2°—3° in diameter, and a few short branches near the summit forming a narrow round-topped head; in open ground usually 20°—30° tall, and often fertile when only a few feet high, with a short thick trunk frequently clothed to the ground, and long horizontal branches, the lower pendulous toward the extremities, the upper sweeping in graceful upward curves and forming a flat-topped often irregular head, and stout branchlets, light orange color when they first appear, soon growing darker and ultimately dark brown. Bark on the lower part of the trunk ¾′—1′ thick and broken into irregularly shaped plates separating on the surface into thin loose dark brown scales tinged with red, higher on the stem, and on the branches dark brown and broken into thin loose scales. Wood light, soft, not strong, brittle, very coarse-grained, pale brown, with thick nearly white sapwood; somewhat used for fuel, and in Pennsylvania manufactured into charcoal.

Distribution. Dry gravelly slopes and ridges of the Appalachian Mountains from southern Pennsylvania to North Carolina, eastern Tennessee and northern Georgia, sometimes ascending to elevations of 3000°, with isolated outlying stations in eastern Pennsylvania, western New Jersey, Maryland, the District of Columbia and Virginia; often forming toward the southern limits of its range pure forests of considerable extent.

28. [Pinus Torreyana] Carr. Torrey Pine.

Leaves forming great tufts at the ends of the branches, stout, dark green, conspicuously marked on the 3 faces by numerous rows of stomata, 8′—13′ long. Flowers from January to March; male yellow, in short dense heads; female subterminal on long stout peduncles. Fruit broad-ovoid, spreading or reflexed on long stalks, 4′—6′ in length, becoming deep chestnut-brown, with thick scales armed with minute spines; mostly deciduous in their fourth year and in falling leaving a few of the barren scales on the stalk attached to the branch; seeds oval, more or less angled, ¾′—1′ long, dull brown and mottled on the lower side, light yellow-brown on the upper side, with a thick hard shell, nearly surrounded by their dark brown wings often nearly ½′ long.

A tree, usually 30°—40° high, with a short trunk about 1° in diameter, or occasionally 50°—60° tall, with a long straight slightly tapering stem 2½° in diameter, stout spreading and often ascending branches, and very stout branchlets bright green in their first season, becoming light purple and covered with a metallic bloom the following year, ultimately nearly black. Bark ¾′—1′ thick, deeply and irregularly divided into broad flat ridges covered by large thin closely appressed light red-brown scales. Wood light, soft, not strong, coarse-grained, light yellow, with thick yellow or nearly white sapwood; occasionally used for fuel. The large edible seeds are gathered in large quantities and are eaten raw or roasted.

MANUAL OF THE TREES OF NORTH AMERICA(EXCLUSIVE OF MEXICO)