Trees of Eastern North America

Trees of Eastern North America

Gil Nelson
Christopher J. Earle
Richard Spellenberg
Illustrations by David More
Edited by Amy K. Hughes
Copyright Date: 2014
Pages: 720
https://www.jstor.org/stable/j.ctt6wq0r5
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  • Book Info
    Trees of Eastern North America
    Book Description:

    Covering 825 species, more than any comparable field guide,Trees of Eastern North Americais the most comprehensive, best illustrated, and easiest-to-use book of its kind. Presenting all the native and naturalized trees of the eastern United States and Canada as far west as the Great Plains--including those species found only in tropical and subtropical Florida and northernmost Canada--the book features superior descriptions; thousands of meticulous color paintings by David More that illustrate important visual details; range maps that provide a thumbnail view of distribution for each native species; "Quick ID" summaries; a user-friendly layout; scientific and common names; the latest taxonomy; information on the most recently naturalized species; keys to leaves and twigs; and an introduction to tree identification, forest ecology, and plant classification and structure. The easy-to-read descriptions present details of size, shape, growth habit, bark, leaves, flowers, fruit, flowering and fruiting times, habitat, and range. Using a broad definition of a tree, the book covers many small, overlooked species normally thought of as shrubs. With its unmatched combination of breadth and depth, this is an essential guide for every tree lover.

    The most comprehensive, best illustrated, and easiest-to-use field guide to the trees of eastern North AmericaCovers 825 species, more than any comparable guide, including all the native and naturalized trees of the United States and Canada as far west as the Great PlainsFeatures specially commissioned artwork, detailed descriptions, range maps for native species, up-to-date taxonomy and names, and much, much moreAn essential guide for every tree lover

    eISBN: 978-1-4008-5299-4
    Subjects: Botany & Plant Sciences, Biological Sciences

Table of Contents

  1. Front Matter
    (pp. 1-4)
  2. Table of Contents
    (pp. 5-6)
  3. INTRODUCTION
    (pp. 7-33)

    This guide presents the trees that grow without the aid of human cultivation in the eastern portion of North America north of Mexico. For the purpose of this book, we have chosen the 100th meridian as the division between East and West. In the United States this meridian defines the eastern border of the Texas panhandle, extends northward across the central portion of the Great Plains, and in Canada lies slightly east of the borders between Saskatchewan and Manitoba, and Northwest Territories and Nunavut. Southward, in Texas, there is a notable difference in the species composition of the woody vegetation...

  4. THE TREES
    • Gymnosperms
      • Conifers
        • GINKGOACEAE: GINKGO FAMILY
          (pp. 35-35)

          Deciduous tree, usually with a single straight trunk, up to 30 m tall and 100 cm diam.; crown rounded or irregular. BARK Gray, with short, irregular furrows. TWIG Gray, bearing stubby, woody short shoots protruding up to 1 cm from the branch at regular intervals, each bearing a cluster of leaves and often a pollen cone or seed. LEAF Slightly leathery, fan-shaped, with a pattern of radiating veins (not seen in any other tree). Blade 5–10 cm broad, light green, turning golden and falling each winter. POLLEN CONE Borne on short shoots, catkin-like. SEED Naked, usually only 1, developing...

        • ARAUCARIACEAE: ARAUCARIA FAMILY
          (pp. 36-37)

          Araucaria, the principal genus of trees in the Araucaria family, is native to the Southern Hemisphere and includes 19 species. Four species are popular ornamentals in warmer areas of the e. U.S., mainly on the Atlantic and Gulf coastal plains from S.C. to Tex. They are tall evergreen trees with a single straight trunk covered in uniform whorls of branches emerging at nearly right angles from the trunk, the branches cloaked in a dense sheath of needle-shaped to triangular leaves. BARK Rough, dark gray, horizontally ridged. LEAF Evergreen, multi-veined, spirally arranged on twigs, branches, and even the trunk. POLLEN CONE...

        • CUPRESSACEAE: CYPRESS FAMILY
          (pp. 38-50)

          Usually a tree. BARK Fibrous, gray. TWIG Flattened, forming flattened sprays. LEAF Scalelike, 1.5–2.5 mm long, lacking conspicuous glands; underside waxy, with white X-shaped marks of stomata. SEED CONE Many cultivars are sterile; seed cones, when present, are globose, 1.5–2 cm diam., slightly waxy, composed of 4 pairs of woody scales.Notes:This plant, which arose in cultivation as a hybrid of Alaska Yellow Cedar (C. nootkatensisD. Don) and Monterey Cypress (C. macrocarpaHartw.), is one of the most popular and diverse ornamental conifers, with dozens of named cultivars. There is great variability in its size and...

        • PINACEAE: PINE FAMILY
          (pp. 51-77)

          There are more than 50 species of firs, distributed through much of the Northern Hemisphere. Firs have a low tolerance for fire and a high tolerance for shade, and live in regions that have snow cover for many months each year. In the East they are native to Canada and the northern tier of states, extending down the Appalachian Mountains to Ga., at elevations from sea-level to nearly 2,000 m. They usually occur in closed-canopy conifer-dominated forests, and are also found near the alpine timberline in woodlands, sometimes as shrubs. Firs can be distinguished from other Pinaceae genera by the...

        • TAXACEAE: YEW FAMILY
          (pp. 78-79)

          The 7 species of yews are primarily trees or shrubs of the forest understory; 3 species are native to North America, with 2 native and 1 introduced species in our range.

          Dioecious or monoecious trees or shrubs, commonly in the forest understory, with an irregular crown of ascending to drooping branches. TWIG Alternate, green to orange, turning brown with age. LEAF Appearing 2-ranked, yellowish to bronze-green, flexible, soft-pointed, with 2 broad whitish stomatal bands on the underside. SEED CONE Orange to red fleshy aril enclosing a single brown seed.

          Many yew populations were decimated in the late 20th century when...

    • Angiosperms
      • Monocots
        • ARECACEAE: PALM FAMILY
          (pp. 80-97)

          Evergreen tree to about 30 m tall, 40 cm diam. Stately, erect, single trunk; crown vase-shaped or rounded, the numerous arching and ascending leaves densely clustered at the top of the trunk and subtended by a smooth, lustrous, medium green crownshaft to about 1.8 m long. TRUNK Medium gray, smooth or slightly roughened, the texture and color reminiscent of concrete; swollen at base, sometimes with a slight bulge at mid-trunk; uppermost portions and the entire trunk of young trees often encircled with prominent brown rings. LEAF Pinnate, to about 4 m long; petiole to about 20 cm long. Blade composed...

      • Dicots
        • ACANTHACEAE: ACANTHUS FAMILY
          (pp. 98-99)

          Evergreen shrub or small tree to about 10 m tall (potentially to 25 m tall in the American tropics) and 30 cm diam. Erect, single short trunk or multiple trunks; crown dense, rounded, branching near the ground. Numerous conspicuous pneumatophores (upright breathing roots) usually form dense thickets below the tree. BARK Smooth on young trees, becoming scaly and fissured with age; gray or dark brown, immediate inner bark bright orange or yellow. TWIG Gray or brown, finely hairy (especially when young), enlarged and ringed at the nodes. LEAF Opposite, simple, thick, leathery; elliptic or oblanceolate, tapering to a blunt point...

        • ADOXACEAE: MOSCHATEL FAMILY
          (pp. 99-106)

          A genus of about 10 species distributed in temperate and subtropical regions; 2 species are native to North America. Deciduous shrubs, small trees, or herbs, the shrubs and trees usually with very soft wood and conspicuous pith; branches usually have raised, vertically elongated lenticels. LEAF Opposite, compound, usually pinnate, sometimes bipinnate, with the lower leaflets also divided; leaflets lanceolate or ovate, margins distinctly toothed. FLOWER Small, white, petals 3–5, stamens 5. FRUIT Round, lustrous red or black berrylike drupe with 3–5 stones. Danewort (S. ebulusL.), a herbaceous species native to Europe and Asia, is reportedly naturalized in...

        • ALTINGIACEAE: SWEETGUM FAMILY
          (pp. 106-107)

          Deciduous tree to about 40 m tall and 1.5 m diam. Erect, single trunk, usually clear of branches on the lower half at maturity, especially when forest-grown; crown rounded, broadly cylindric, or pyramidal. BARK Grayish or greenish gray, finely to moderately fissured, sometimes with corky outgrowths. TWIG Greenish, finely hairy, often slightly angled, often developing corky wings or outgrowths. LEAF Alternate, simple, palmately 5- to 7-lobed, nearly star-shaped; base usually flattened; tips of lobes pointed; margins toothed. Upper surface lustrous green, hairless, lower surface paler, hairy at least in the lower vein axils. Blade 6–12 cm long, 10–18...

        • ANACARDIACEAE: CASHEW FAMILY
          (pp. 108-117)

          A small genus of 5 species distributed in Europe, Asia, and North America. It is composed of shrubs or small trees with alternate unifoliolate leaves, yellow wood, pungent sap, and hairy inflorescences that are often nearly devoid of fruit.

          Deciduous large shrub or small tree, 10–30 m tall, to 48 cm diam. Erect or vase-shaped, usually with multiple trunks, sometimes developing a single dominant trunk with age; crown rounded, dense, branches spreading and often drooping with age; wood yellow. BARK Scaly, strongly aromatic when crushed. TWIG Covered with a whitish bloom when young, eventually becoming brown, with whitish corky...

        • ANNONACEAE: CUSTARD APPLE FAMILY
          (pp. 118-121)

          A genus of about 110 species, distributed mostly in the New World tropics, with a few in North America and Africa. Evergreen or deciduous trees and shrubs, easily recognized by their fleshy, aggregate fruit. BARK Thin, often scaly or fissured. LEAF Alternate, simple, leathery or papery. FLOWER Creamy white or yellowish; petals 6 or 8, fleshy, produced in 2 series of 3 or 4; sepals 3 or 4, distinctly smaller than the petals, usually falling early. FRUIT Fleshy, ovoid or rounded syncarp (aggregate of fused berries), 1 per flower.

          Evergreen or late deciduous, with leaves falling as new leaves develop;...

        • APOCYNACEAE: OLEANDER FAMILY
          (pp. 122-125)

          Evergreen fast-growing tree to about 20 m tall. Erect, single trunk; crown open, branches more or less ascending and spreading. BARK Smooth, gray. TWIG Smooth, gray; young twigs exuding milky sap when broken. LEAF Usually in whorls of 3 or 4, rarely opposite; simple, leathery, obovate or elliptic, usually widest near, or slightly above, the middle; base wedge-shaped; tip abruptly pointed; margins entire. Upper surface lustrous green, hairless; lower surface paler, hairy (at least when young). Blade 10–30 cm long, 4–14 cm broad; petiole 1–4 cm long. FLOWER 5–10 mm long, white, tubular, flaring into 5...

        • AQUIFOLIACEAE: HOLLY FAMILY
          (pp. 126-141)

          Deciduous and evergreen trees and shrubs. BARK Gray or mottled gray, often marked with darker and lighter splotches; usually smooth, often with distinctive lenticels. TWIG Usually gray or brown, often bearing circular or elongated lenticels; deciduous species often produce short leafy shoots with leaves closely clustered at the tip and appearing whorled. LEAF Alternate, simple; margins usually toothed, rarely entire, teeth sometimes spine-tipped. FLOWER Functionally unisexual, usually male and female flowers on separate trees (sometimes with a few bisexual flowers intermingled, predominantly on cultivated plants). Female flowers typically have a plump, conspicuous, functional ovary surrounded by several obviously nonfunctional stamens...

        • ARALIACEAE: GINSENG FAMILY
          (pp. 142-145)

          Evergreen tree, 10–13 m tall, 20–35 cm diam. Erect or leaning, single trunk or multiple; crown spreading, often dense, sometimes forming an umbrella-like canopy on single-trunked trees. BARK Smooth, grayish green or green. LEAF Alternate, crowded at branch tips and sometimes appearing whorled; palmately compound, blade outline circular, to about 50 cm broad; petiole 20–45 cm long, subtended by a pair of conspicuous stipules. Leaflets 5–18, radiating from a central disk at the apex of the petiole, each 8–30 cm long, 4–12 cm broad, oblong or narrowly elliptic, margins entire. Upper surface lustrous green...

        • ASTERACEAE: ASTER FAMILY
          (pp. 146-146)

          Tardily deciduous or nearly evergreen vase-shaped shrub or small tree, to about 4 m tall, usually with multiple trunks. LEAF Alternate, simple, obovate, narrowed at the base, margins usually coarsely toothed; grayish green, gland-dotted on both upper and lower surfaces. Blade 4–7 cm long, 1–4 cm broad. FLOWER Unisexual, the sexes borne on separate plants. Male inflorescences yellowish and compact; female flowers become whitish at maturity from the conspicuous, cottonlike tufts of bristles that provide buoyance and aid in seed distribution.

          HABITAT/RANGE Native; marshes, coastal swales, shores, from N.Y. south to Fla., west to e. Tex.; formerly perhaps...

        • BETULACEAE: BIRCH FAMILY
          (pp. 147-165)

          A genus of about 25 species, 8 in North America, of which 3 are introduced. Six species occur in the East, 5 native. Deciduous shrubs or small trees, usually with several trunks. BARK Oft en waxy gray at first, usually with conspicuous horizontal orange or reddish-brown lenticels, remaining smooth or splitting with age to reveal reddish-brown inner bark. TWIG Green, brown, or purplish, 2-ranked or diffusely spreading, of uniform or variable length, hairy or not. BUD Usually stalked, sessile in some species, lateral or near the twig tip. LEAF Alternate, simple, thin or leathery; margins finely or coarsely toothed. FLOWER...

        • BIGNONIACEAE: BIGNONIA FAMILY
          (pp. 166-174)

          A genus of 9 species distributed in North America, the Greater Antilles, and East Asia; 3 occur in North America, 2 native. Deciduous trees, usually with a single erect trunk. LEAF Opposite or whorled, simple, heart-shaped, with 5 veins arising from the base of the blade; margins entire. Leaves are potentially confused with those of Princesstree (Paulownia tomentosa, Paulowniaceae), which is sometimes included within the Bignoniaceae. FLOWER Bisexual; usually white or pale yellow, purple-spotted in the throat or lower lip, petals 5, fused. FRUIT Narrow, elongate, many-seeded capsule that looks like a bean pod but splits along only 1 seam....

        • BORAGINACEAE: BORAGE FAMILY
          (pp. 174-178)

          A genus of about 50 species distributed in the warmer regions of the Americas; 3 species are native to North America, all restricted to s. Fla., including Fla. Keys. Two of our species are listed as endangered.

          Evergreen, typically a shrub, rarely a small tree to about 12 m tall, 17 cm diam. Erect or ascending, single trunk or multiple; crown dense, rounded, tips of branches often drooping. BARK Reddish brown, scaly. LEAF Alternate, simple, elliptic, margins entire. Upper surface lustrous dark green, hairy, the hairs stiff and rough to the touch; lower surface paler. Blade 2.5–6.5 cm long,...

        • BURSERACEAE: TORCHWOOD FAMILY
          (pp. 178-179)

          Semideciduous tree, to about 20 m tall, 1 m diam., losing and quickly replacing its leaves in spring. Erect, single trunk; crown open, spreading, with several lateral branches. BARK Smooth, lustrous, reddish brown, often flaking off in curly plates; outer bark resinous, with the aroma of turpentine. TWIG Hairy. LEAF Alternate, pinnately compound, blade 15–20 cm long, 10–15 cm broad, petiole 3–8 cm long. Leaflets 3–9, ovate or oblong, strongly asymmetric, especially at base; tip acuminate, concavely tapering to a short point; margins entire; leaflet blade 6–7.5 cm long, 2–5 cm broad, stalk 3–...

        • CACTACEAE: CACTUS FAMILY
          (pp. 180-180)

          An erect, leafless, sparsely branched, cylindric cactus to about 7 m tall, 10 cm diam. Trunk succulent, with yellow spines, lower portion brown and appearing woody, upper portion green. FLOWER Bell-shaped, 5–6 cm long; petals 1–1.5 cm long; inner petals white, outer petals greenish; produced late afternoon and evening, wilting after sunrise. FRUIT Red drupe, about 5 cm long.

          HABITAT/RANGE Native. Subtropical hammocks; rare and local in a few hammocks on Fla. Keys....

        • CANELLACEAE: WILD CINNAMON FAMILY
          (pp. 180-181)

          Evergreen shrub or small tree, 10–15 m tall, to about 20 cm diam. Erect, single trunk or multiple; crown dense, small, narrow, and more or less vertically elongate. BARK Grayish brown, becoming scaly and fissured at maturity; inner bark aromatic, with a cinnamon-like fragrance when crushed. LEAF Alternate, simple, obovate, rounded at the tip, tapering to a narrowed base; margins entire. Upper surface dark, lustrous green, veins obscure, tissue with pellucid dots; lower surface paler. Blade 7–13 cm long, 1–5 cm broad; petiole 3–8 mm long, usually grooved on the upper surface. FLOWER Petals 5, deep...

        • CANNABACEAE: HEMP FAMILY
          (pp. 182-187)

          A genus of 70–100 species distributed nearly worldwide in all but the coldest regions, occurring from low to moderate elevations; 6 species occur in the East, one essentially a shrub.

          Deciduous shrubs or trees. BARK Thick, gray, smooth, with raised, warty, corky protuberances often developing on older parts. LEAF Alternate, simple, harshly to softly hairy or hairless, the tip pointed, the base round or heart-shaped, often asymmetric; margins toothed or entire; 3 primary veins from the base of the blade, often these and sometimes smaller veins raised on the lower surface. FLOWER Usually functionally unisexual, a few bisexual, male...

        • CAPPARACEAE: CAPER FAMILY
          (pp. 188-189)

          A genus of about 250 species, 3 in North America. Two species are sometimes included in the genusQuadrella, including Jamaican Caper, treated here, andCapparis incanaKunth, a shrub of extreme s. Tex. Bay-leaved Caper is sometimes included within the genusCynophalla.

          Evergreen shrub or small tree to about 6 m tall. BARK Reddish brown. LEAF Alternate, simple, leathery, ovate or elliptic; tip acute or concavely tapering to a short point (acuminate), often notched; margins entire. Lower surface densely covered with visible scales. Blade 5–15 cm long, 2.5–8 cm broad; petiole 6–21 mm long. FLOWER Bisexual,...

        • CASUARINACEAE: SHE-OAK FAMILY
          (pp. 190-191)

          A genus of 17 species, 3 of which are naturalized in the s. half of Fla., native to Australia, Indonesia, and Asia, and recognized among Florida’s most aggressive invasive species. All 3 species are commonly referred to as Australian-pine, a reference to the similarity of their branchlets to pine needles and the conelike shape of their small fruits. LEAF The true leaves are tiny and scalelike, and encircle the branchlets at regular intervals. The number of leaves per encircling whorl provides the primary means for distinguishing one species from another.

          Evergreen tree, 15–35 m tall, with a single erect...

        • CECROPIACEAE: CECROPIA FAMILY
          (pp. 192-192)

          Deciduous or semi-evergreen fast-growing, short-lived tree to 15 m tall, 18 cm diam. Erect, single trunk; crown spreading, with few stout branches that arise high on the trunk. BARK Smooth, brown or brownish gray, usually ringed with narrow leaf scars at regular intervals of 5–10 cm. LEAF Alternate, simple, nearly circular, with 7–11 deep lobes, peltate, with the stout green petiole attached near the base of the blade. Upper surface medium or dark green, slightly roughened, hairless; lower surface with a conspicuous covering of whitish hairs. Blade 25–45 cm long, 15–40 cm broad; petiole 25–50...

        • CELASTRACEAE: STAFF TREE FAMILY
          (pp. 193-201)

          A shrub, rarely a small, short-trunked tree to about 6 m tall. LEAF Opposite, rarely alternate or whorled, simple, obovate to spatulate, margins bluntly toothed; blade 1–4 cm long, 5–20 mm broad; petiole 1–3 mm long. FLOWER Green with reddish petals, to about 2 mm diam. FRUIT Round red or purplish-red drupe, 5–7 mm diam.

          HABITAT/RANGE Native; pinelands, occasionally subtropical hammocks; southernmost Fla.

          A genus of about 130 species distributed in Asia, Australasia, Europe, Madagascar, and North America; 13 species, 5 of them native, occur in North America; 12 species are found in the East, 4...

        • CERCIDIPHYLLACEAE: KATSURA TREE FAMILY
          (pp. 202-202)

          Deciduous tree, 10–20 m tall. Erect, single main trunk; crown pyramidal or ovoid, to about 10 m broad; sweetly aromatic in autumn. BARK Brown, shaggy, peeling and curling in thin strips. TWIG Hairless. LEAF Opposite, rarely sub-opposite or alternate on new shoots, simple; obovate, broadly elliptic, or nearly rounded, base heart-shaped, margins bluntly toothed. Upper surface reddish purple when new, green at maturity, hairless, venation palmate, prominent; lower surface hairless or hairy in the vein axils. Turns brilliant burnt orange in autumn. Blade of typical leaves 3.7–9 cm long, 5–8.3 cm broad (blades on leaves of elongate...

        • CHRYSOBALANACEAE: COCO PLUM FAMILY
          (pp. 203-203)

          Evergreen large shrub or small bushy tree to about 5 m tall, 7–15 cm diam. Erect or more often leaning, usually with a single short trunk and numerous low branches; crown rounded, dense. BARK Thin, brownish. TWIG Reddish brown, hairless. LEAF Alternate, simple, thick, leathery; broadly elliptic, oval, obovate, or nearly circular; tip sometimes notched; margins entire. Upper surface dark lustrous green, hairless; lower surface duller, usually hairless. Blade 2–8 cm long, 1–6 cm broad; petiole to about 5 mm long, thickened, usually twisted so all leaves are oriented to same side of branch. FLOWER Bisexual, white,...

        • CLETHRACEAE: WITCH ALDER FAMILY
          (pp. 204-204)

          Deciduous shrub, rarely a small tree to about 6 m tall. Erect, single short trunk or multiple. BARK Brownish or reddish brown, peeling and shredding into thin plates. TWIG Light brown or light reddish brown, with patches of star-shaped hairs and a single, prominent internodal ridge; terminal bud 3–6 mm long, yellowish, silky, larger than the lateral buds. LEAF Alternate, simple, often crowded near the tip of the twig, elliptic or lanceolate, tip acuminate (concavely tapered to an abrupt point); margins finely and distinctly toothed. Upper surface dark green, hairless; lower surface hairless or with a few star-shaped hairs....

        • CLUSIACEAE: GARCINIA FAMILY
          (pp. 205-207)

          Evergreen, salt-tolerant tree to about 12 m tall and 75 cm diam. in Fla., potentially taller in its native range. Erect, usually single trunk, sometimes with multiple low branches; crown dense, rounded, usually with large spreading branches. BARK Dark gray or nearly black; deeply ridged and furrowed, the ridges often crisscrossing and forming a diamond pattern. LEAF Opposite, simple, thick, stiff, elliptic or oval; tip rounded or notched; margins entire. Upper surface lustrous dark green, veins numerous, closely set, parallel, terminating at the margin; lower surface dull green. Blade 5–8 cm long, 3–6 cm broad; petiole 5–15...

        • COMBRETACEAE: WHITE MANGROVE FAMILY
          (pp. 208-213)

          Evergreen shrub or tree, to 20 m tall, 38–139 cm diam. Erect, single trunk; crown dense, irregular, more or less rounded or cylindric. BARK Gray or brown, scaly, usually fissured, with broad ridges. TWIG Slender, usually winged, hairless or finely hairy, yellowish at first, becoming gray or brownish. LEAF Alternate, simple, leathery; elliptic, lanceolate, or oblanceolate, usually with a tiny sharp point at the tip; base usually with 2 glands near the point of attachment with the petiole; margins entire. Upper surface yellowish green; lower surface paler, hairless or silky-hairy, usually with tiny pockets in the vein axils. Blade...

        • CORNACEAE: DOGWOOD FAMILY
          (pp. 214-221)

          A genus of about 55 species distributed mostly in north temperate regions; 20 species and several hybrids occur in North America, 16 native.

          Deciduous shrubs or trees, often with multiple trunks, at least 1 species low-growing and appearing herbaceous. LEAF Opposite, simple; margins entire or slightly wavy; pairs of arching veins, the tips of the veins paralleling the leaf margins. The leaf veins exude strands of stringy material when the leaves are transversely folded, creased, and gently pulled apart, a characteristic often referred to as the “Cornustest.” FLOWER Bisexual, radially symmetric, petals 4, stamens 4, produced in loose or...

        • CYRILLACEAE: TITI FAMILY
          (pp. 222-223)

          Evergreen shrub or small, slender tree to about 18 m tall and 60 cm diam. Erect, single trunk or multiple, often somewhat contorted. Crown dense, irregular, especially on isolated plants in sunny locations; plants in swamps and along swampy margins often form dense stands with their crowns intermixed. BARK Smooth, dark gray or nearly black, becoming shallowly fissured on old trees. TWIG Grayish. LEAF Alternate, simple, leathery, elliptic or slightly wider above the middle; tip bluntly pointed; margins entire. Upper surface dark green, veins obscure; lower surface paler, sometimes with a bluish-white tinge. Blade 2.5–10 cm long, 1.2–1.8...

        • EBENACEAE: EBONY FAMILY
          (pp. 224-225)

          A genus of about 480 species, constituting about 90% of the ebony family. Distributed in tropical and warm temperate regions, nearly half occurring naturally on the Malay Archipelago. Two native species occur in North America, 1 in the East; 2 introduced species are sparingly naturalized in Fla.

          Deciduous trees or shrubs, usually with hard, dense wood. BARK Often dark or blackish, usually blocky or scaly. LEAF Alternate, simple, more or less leathery, margins usually entire (in species covered); petiole often glandular. FLOWER Unisexual, urn-shaped; petals 3–7, often recurved at the apex; sepals 3–7; ovary superior. FRUIT Large, several-seeded...

        • ELAEAGNACEAE: OLEASTER FAMILY
          (pp. 226-228)

          Deciduous thorny shrub or very small tree, 3–8 m tall; crown rounded, dense or spreading. LEAF Alternate, simple; narrowly linear; margins entire. Surfaces vested with silvery scales. Blade 2.5–8 cm long, stalkless. FLOWER Unisexual, male and female on separate plants, tiny, yellow, produced in spikes (male) or axillary clusters (female) prior to new leaf growth. Spring. FRUIT Drupelike, rounded or ellipsoid, 6–10 mm long, bright orange; seed dark brown to nearly black; matures late spring, persisting through winter.

          HABITAT/RANGE Introduced; cultivated in North America for its grayish foliage and abundant orange fruit; naturalized in Que., Sask., and...

        • ERICACEAE: HEATH FAMILY
          (pp. 228-236)

          Deciduous shrub or small tree, 2–12 m tall, 5–20 cm diam. Erect or leaning, single trunk; crown narrow, with ascending branches. BARK Gray, furrowed when young, becoming blocky and similar to that of Sourwood (Oxydendrum arboreum). TWIG Greenish or orange-brown when young, becoming grayish brown and roughened. LEAF Alternate, simple, ovate, oblong, or narrowly elliptic; base tapered or wedge-shaped; tip acute or abruptly pointed, with a short bristle at the apex; margins entire, flat. Upper surface dark green, hairless; lower surface paler, sparsely hairy. Blade 5–12 cm long, 2–4.5 cm broad; petiole 6–14 mm long....

        • EUPHORBIACEAE: SPURGE FAMILY
          (pp. 236-247)

          Aleuritesis a genus of about 5 species distributed in Asia and Hawaii, at least two of which occur in the Southeast.

          Deciduous tree to about 12 m tall, 40 cm diam. Erect, single trunk; crown rounded. BARK Gray, smooth or slightly roughened. TWIG Stout, hairless, developing oblong lenticels; exuding milky sap when broken. LEAF Alternate, simple, ovate, often 3-lobed; base heart-shaped or truncate; tip abruptly sharp-pointed; margins entire, sinuses of marginal lobes often with conspicuous glands. Upper surface dark green, hairless, with 5 primary veins arising from the base; lower surface paler, gray-green, usually hairy. Blade 5–30 cm...

        • FABACEAE: BEAN OR PEA FAMILY
          (pp. 248-293)

          The subfamily Caesalpinioideae includes the sennas, cassias, orchid trees, locusts, redbuds, and their relatives. It is primarily tropical and subtropical, consists mostly of shrubs and trees, and includes about 180 genera and 3,000 species. LEAF Alternate, occasionally clustered; usually pinnate, sometimes bipinnate, or sometimes unifoliolate and appearing simple; in some species, especially in the genusSenna, the petiole beard glands. FLOWER Usually bisexual, more or less bilateral, the upper petal positioned interior to the lateral petals (wings) and enclosed by them in bud; stamens 10 or fewer, separate or at least partially united, often opening by terminal pores.

          Bauhiniais...

        • FAGACEAE: BEECH OR OAK FAMILY
          (pp. 294-349)

          Castaneaincludes as many as 10 species in North America, Europe, and Asia. Seven species occur in North America, of which 4 are native; none occurs in the West. Most species in the genus are similar in leaf and fruit and are difficult to distinguish from one another; chestnuts can be distinguished from other trees by the combination of alternate leaves with bristle-tipped marginal teeth, conspicuous parallel lateral leaf veins, and the spiny cupule enclosing 1–3 nuts.

          Deciduous shrubs and trees ranging from small shrubs 1 m tall to huge single-trunked trees 30 m tall, with a trunk to...

        • HAMAMELIDACEAE: WITCH-HAZEL FAMILY
          (pp. 350-351)

          A genus of 4 or 5 species, 3 native to North America, all confined to the eastern half of the U.S.

          Deciduous shrubs or trees, often suckering from the base, recognized by scalloped leaves and straplike flower petals. Erect, single trunk or multiple. BARK Gray, often mottled with darker gray or brown splotches. TWIG Finely covered with star-shaped hairs. LEAF Alternate, simple, usually broadly elliptic, margins scalloped. FLOWER Bisexual; petals 4, usually ribbon- or straplike; corolla yellow, red, or orange-red; functional stamens 4, nonfunctional stamens 4; styles 2. FRUIT Two-valved woody or leathery capsule; seeds 2 per capsule, lustrous black,...

        • ILLICIACEAE: STAR ANISE FAMILY
          (pp. 352-352)

          Evergreen shrub, rarely a small understory tree, to about 8 m tall. Erect or ascending, single trunk or multiple. TWIG Tip of twig red at first, becoming gray, hairless. LEAF Alternate, those at the tip of the branch often closely set and appearing whorled; somewhat leathery, simple, narrowly elliptic, bluntly pointed at tip; margins entire. Upper surface dark green, veins obscure, hairless; lower surface minutely gland-dotted. Blade 6–20 cm long, 2–6 cm broad; petiole 1–2 cm long, often reddish. FLOWER 2.5–6 cm diam., red; sepal-like bracts 3–6, tepals 21–33, pistils 11–15, stamens 30–...

        • JUGLANDACEAE: WALNUT FAMILY
          (pp. 353-368)

          A genus of 21 species worldwide growing from low to moderate elevations, 6 native to North America, at least 3 introduced, rarely naturalized; 4 species in the East, 2 native.

          Deciduous large shrubs or trees. BARK Smooth and gray when young, often fissured and scaly when older. TWIG Usually covered with glandular hairs; pith chambered, brown; leaf scars triangular or 3-lobed; terminal buds bluntly pointed, usually flattened, hairy. LEAF Alternate, pinnately compound, usually with a terminal leaflet (odd-pinnate), often with a spicy scent; foliage yellowish in autumn. FLOWER Unisexual, male and female borne on the same tree. Spring. FRUIT Globose...

        • LAURACEAE: LAUREL FAMILY
          (pp. 368-377)

          Evergreen small to potentially large tree, to about 20 m tall, 2 m diam. Erect, with a single short trunk, sometimes producing several secondary trunks from the base; crown dense, oval, lustrous, often with low, spreading branches that become more or less ascending in the mid- and upper crown. BARK Dark cinnamon brown to dark steel gray, on young trees smooth or finely fissured, becoming more deeply furrowed at maturity; crushed bark with a camphorlike aroma. TWIG Green, often suffused with red, hairless. LEAF Alternate, simple, usually somewhat leathery at maturity, giving off a strong odor of camphor when crushed;...

        • LEITNERIACEAE: CORKWOOD FAMILY
          (pp. 378-378)

          Deciduous shrub or small tree, to about 5 m tall, 6 cm diam. Erect, single straight trunk; crown narrow, typically unbranched or nearly so. BARK Reddish brown, usually with conspicuous buff-colored corky lenticels. LEAF Alternate, simple, narrowly elliptic; margins entire. Upper surface lustrous, medium green, hairy at first, soon becoming hairless; lower surface paler, hairy at maturity. Blade 5–17 cm long, 2–5 cm broad; petiole 2–4 cm long. FLOWER Unisexual, male and female flowers borne on separate plants; male flowers in upright grayish-brown catkins 2–5 cm long along the upper part of the main stem; female...

        • LYTHRACEAE: LOOSESTRIFE FAMILY
          (pp. 379-379)

          Deciduous shrub or small tree to 7 m tall, 15 cm diam. Erect, single trunk or multiple; crown ascending and vase-shaped, rounded, or spreading. BARK Orange-brown, flaking and curling to reveal smooth inner bark. LEAF Alternate and sub-opposite on the same branch, simple, elliptic, obovate, ovate, or nearly rounded; margins entire. Upper surface lustrous green, usually hairless; lower surface paler, hairless or with minute hairs along the veins. Blade 2–6 cm long, 1–4 cm broad; petiole lacking or to about 2 mm long. FLOWER Averages about 3 cm diam., bisexual; petals usually 6, with crinkly margins, varying white,...

        • MAGNOLIACEAE: MAGNOLIA FAMILY
          (pp. 380-390)

          Deciduous large, sometimes massive tree, to 45 m tall, 3 m diam., commonly about half this size. Erect, single straight trunk; crown pyramidal and low-branching on open-grown trees, branching much higher on old trees. BARK Smooth or finely furrowed and whitish gray when young, becoming deeply and coarsely furrowed and darker gray at maturity. TWIG Stout, hairless at maturity, reddish brown or purplish, aromatic when crushed; pith whitish, chambered, solid between green partitions; terminal bud laterally flattened, rounded at the apex. LEAF Alternate, simple, somewhat thickened and firm, deeply and broadly notched at the tip into 2 lateral lobes, rounded...

        • MALPIGHIACEAE: MALPIGHIA FAMILY
          (pp. 391-391)

          Evergreen large shrub or small shrubby tree to about 6 m tall. Erect or leaning, usually with multiple trunks or branches arising from near the base; crown of tree-size plants open, with spreading branches. BARK Smooth, light brown. TWIG Jointed. LEAF Opposite, simple, leathery, oblanceloate or spatulate; tip acuminate or rounded. Upper surface lustrous, dark green; lower surface paler. Blade 2–6 cm long, 0.5–2 cm broad; petiole short, thick, clasping the stem. FLOWER Bisexual, petals 5, white at first, becoming pink, then crimson at maturity, with all 3 colors usually represented on a single plant; sepals 5, each...

        • MALVACEAE: MALLOW FAMILY
          (pp. 392-401)

          Evergreen shrub or small tree to about 4 m tall, to about 6 cm diam. Vase-shaped or shrubby with 1 or more trunks; crown spreading, usually broader than tall. TWIG Hairy. LEAF Opposite, simple, usually with 3, occasionally 5, conspicuous lobes; base usually heart-shaped, rarely rounded; tips of lobes acute; margins not toothed. Upper surface medium green, the veins palmate, conspicuous; lower surface paler, conspicuously hairy with branched hairs. Blade 5–15 cm long, 5–15 cm broad; petiole 6–11 cm long, hairy. FLOWER Bisexual, petals 5, 3–6 cm long, whitish or yellow, aging purplish or pinkish, usually...

        • MELASTOMATACEAE: MELASTOME FAMILY
          (pp. 402-402)

          Evergreen shrub or small tree, to about 10 m tall, 6–10 cm diam.; usually shrubby, occasionally becoming arborescent in hammocks. Erect, single trunk or multiple. LEAF Opposite, simple, lanceolate, often somewhat curved; margins entire. Upper surface lustrous, dark green with 2 conspicuously depressed longitudinal veins near the margins that are joined by numerous depressed lateral veins, giving the blade a quilted appearance; lower surface whitish-scaly with raised veins. Blade 7–12 cm long, 2–4 cm broad; petiole 1.5–2 cm long. FLOWER Bisexual; petals 5, white, falling readily if touched; stamens 10, yellow; pistil 1, often protruding while...

        • MELIACEAE: MAHOGANY FAMILY
          (pp. 403-405)

          Deciduous tree to about 30 m tall, with a rounded, spreading crown. LEAF Alternate, pinnately compound; leaflets usually 9–15 pairs, each 9–13 cm long, 3–5 cm broad, with tip abruptly and conspicuously tapering to a narrow, elongated point. FLOWER Unisexual, 3.5–6 mm diam., fragrant; inflorescence about 55 cm long, pendent, the axis hairy. FRUIT Capsule, 1.5–2.5 cm long. HABITAT/RANGE Introduced from Asia and Australia; cultivated, reportedly naturalized in Md.Notes: Toonais a genus of about 5 species distributed in Asia and Australia.

          Evergreen or semideciduous tree, 15–25 m tall, 30–140 cm diam....

        • MORACEAE: MULBERRY FAMILY
          (pp. 406-417)

          A genus of about 10 species, widespread in tropical and temperate regions; 4 occur in North America, 2 native in the East, 2 introduced.

          Deciduous shrubs and trees with milky sap. LEAF Alternate, simple, often deeply lobed, the margins entire or toothed. FLOWER Tiny, borne in unisexual catkins, the sexes on the same or separate plants; corolla absent, male flowers with 4 thin tepals and 4 inflexed stamens; pistillate flowers with 4 thickish tepals, 2 large, 2 smaller, the ovary superior, with 2 styles. FRUIT Aggregate of achenes (a syncarp), each achene enclosed in a juicy, fleshy calyx; syncarp cylindric,...

        • MORINGACEAE: HORSERADISH-TREE FAMILY
          (pp. 418-418)

          Evergreen shrub or tree, to about 12 m tall, 40 cm diam. Erect, single trunk; crown rounded, somewhat irregular. BARK Gray or greenish gray, smooth or slightly roughened. LEAF Alternate, tripinnately compound, with 4–6 lateral segments and a terminal segment; blade 30–60 cm long, exuding a strong aroma of horseradish when crushed or bruised. Ultimate leaflets 75–150 in number, 10–20 mm long, 5–12 mm broad, more or less rounded at base and tip. FLOWER Creamy white or yellowish, pea-like, to about 2.5 cm broad; petals 5, each about 1 cm long; borne in drooping, many-flowered...

        • MUNTINGIACEAE: MUNTINGIA FAMILY
          (pp. 418-419)

          Evergreen shrub or tree, 5–7 m tall; more often shrubby where naturalized in North America. Erect, single trunk; crown flat-topped, with laterally spreading branches. BARK Gray. TWIG Densely covered with soft glandular hairs, often slightly sticky. LEAF Alternate, simple; lanceolate, oblong, or narrowly ovate; base oblique, asymmetric; tip abruptly pointed; margins coarsely toothed. Upper surface green, smooth; lower surface grayish white, with a dense covering of stellate hairs. Blade 5–14 cm long, 1.5–5 cm broad; petiole 2–6 mm long. FLOWER Bisexual, about 2 cm diam., radially symmetric; petals 5, white, crinkled, about 1 cm long, nearly...

        • MYOPORACEAE: MYOPORUM FAMILY
          (pp. 420-420)

          Evergreen shrub or small tree to about 8 m tall, 15 cm diam. Erect, single trunk or multiple; crown narrowly vertical, densely foliaged. BARK Pale brown, thick, furrowed. LEAF Alternate, simple, oblong to narrowly lanceolate or nearly linear; base and tip evenly tapering; margins entire. Upper and lower surfaces pale green. Blade 3–11 cm long, 1–3 cm broad; petiole 2–10 mm long. FLOWER Tubular, about 2 cm long, yellow and purple, flaring at the tip into 2 lobes, the lower conspicuously marked with a line of purplish hairs. Year-round. FRUIT Fleshy, single-stoned, long-stalked drupe, to about 1...

        • MYRICACEAE: WAX MYRTLE FAMILY
          (pp. 420-423)

          Some authorities include several species ofMyricawithin the genusMorella, differentiating the 2 genera on the position of the catkin, size of the bracts subtending male flowers, and appearance of the fruit. Here we have retained the traditional classification. LEAF Alternate, simple. FLOWER Unisexual, produced on separate plants, lacking sepals and petals. FRUIT Rounded waxy nutlike drupe that is often bumpy on the outer surface from the presence of warty protuberances. Species ofMyricaare the source of bayberry candles.

          Evergreen shrub or small tree, to about 12 m tall, potentially to about 32 cm diam., usually not exceeding...

        • MYRSINACEAE: MYRSINE FAMILY
          (pp. 424-426)

          A genus of 400–500 species, 5 in North America, 1 native. Distributed in the subtropical U.S., Mexico, the West Indies, Central and South America, Asia, Indian Ocean islands, Pacific islands, Australia.

          Evergreen shrubs or trees. LEAF Alternate, simple; surfaces hairless or with glandular dots; margins toothed or entire. FLOWER Bisexual, white to pink; sepals 4 or 5, green; petals usually 5, white or pinkish; produced in terminal, subterminal, or axillary panicles, racemes, cymes, or umbels. FRUIT Single-seeded, rounded fleshy drupe, 4–8 mm diam., red, white, or black.

          Evergreen large shrub or small tree, usually not exceeding about 3...

        • MYRTACEAE: MYRTLE FAMILY
          (pp. 426-443)

          A genus of about 100 evergreen trees and shrubs distributed in the American tropics and subtropics. LEAF Opposite, simple, usually leathery. FLOWER Bisexual, petals absent; calyx cuplike, forming a circular, lidlike cap at the summit that dehisces but remains partially attached as the stamens expand; ovary inferior; stamens numerous; inflorescence a many-flowered panicle. FRUIT Berry with 1 to few seeds, the basal part of the calyx remaining attached at maturity.

          Evergreen shrub or small tree, usually to about 8 m tall in Fla. Usually shrubby, single trunk or multiple; crown dense or open. BARK Smooth or scaly, gray. TWIG Slender,...

        • NYCTAGINACEAE: FOUR-O’CLOCK FAMILY
          (pp. 444-445)

          Deciduous, nearly evergreen, quickly replacing fallen leaves; shrub or small spreading tree, 4–5 m tall (potentially to 8.6 m), potentially to 30 cm diam., usually much smaller in Fla. Erect, single trunk or multiple, often low-branching; crown dense, rounded or oval with numerous ascending, unarmed branches. BARK Ashy gray, with conspicuous leaf scars. TWIG Yellowish green, stout, densely or finely hairy, becoming hairless or nearly so. LEAF Opposite or sub-opposite, youngest leaves often produced singly at a node, simple, leathery, stiffish, oval or broadly elliptic; base rounded or broadly wedge-shaped; tip rounded, often notched; margins entire, sometimes slightly revolute....

        • NYSSACEAE: TUPELO FAMILY
          (pp. 446-449)

          The tupelos genus includes 5 species, all native and essentially eastern in distribution. Species ofNyssaare deciduous trees or shrubs with furrowed, blocky grayish bark. LEAF Alternate, simple. FLOWER Usually unisexual, produced on separate trees (rarely some trees predominantly with bisexual flowers). FRUIT Single-stoned drupe.

          Several trees of this genus are well known as the source of tupelo honey, a product of the Deep South, where expansive tupelo-dominated swamps are abundant. The common name “gum” is used for several species, an apparent misnomer as none produces gumlike latex. At least 2 species (Sour Gum and Blackgum) are used horticulturally....

        • OLEACEAE: OLIVE FAMILY
          (pp. 450-466)

          Chionanthusis a largely tropical and subtropical genus of about 80 shrubs and trees with 2 species in the e. U.S.

          Deciduous small tree or large shrub to about 10 m tall, 20 cm diam. Erect, single trunk or multiple, often branching very near or at ground level; crown rounded. BARK Grayish when young, becoming reddish brown and slightly scaly with age. TWIG Reddish brown when young, becoming gray, hairless, decorated with widely scattered circular, slightly elevated tan lenticels that are interspersed with numerous dark dots. LEAF Opposite, simple, broadly lanceolate, elliptic, oval, or oblong; base and tip tapered; margins...

        • PAULOWNIACEAE: PRINCESSTREE FAMILY
          (pp. 466-467)

          Deciduous tree, 18–20 m tall, to 60 cm diam. Erect, single trunk; crown rounded, spreading, moderately dense, with thick, often contorted branches. BARK Grayish brown, thin, slightly roughened and fissured. TWIG Stout, usually sticky, at least when young, with a hollow pith and conspicuous white lenticels. LEAF Opposite, simple, moderately thick, broadly ovate, base usually heart-shaped, tip pointed, often abruptly so; margins usually entire, often with 3–5 lobes, sometimes coarsely toothed, especially on young plants. Upper surface dark green, sparsely hairy; lower surface paler, sparsely to more often densely hairy. Blade 14–40 cm long, 8–30 cm...

        • PICRAMNIACEAE: BITTERBUSH FAMILY
          (pp. 468-468)

          Evergreen tree, 5–15 m tall, to about 20 cm diam. TWIG Hairy, jointed. LEAF Alternate, pinnately compound, blade 10–30 cm long, 4–5 cm broad; petiole to about 3 cm long. Leaflets 19–41, alternate and opposite along the rachis, each 1–2.5 cm long, less than 1 cm broad; oval or oblong; margins entire. Upper surface hairless; lower surface silkyhairy. FLOWER Unisexual, small, green or yellowish; male racemes to 20 cm long; female racemes to 13 cm long. Winter to spring. FRUIT Flattened, lanceolate, samara-like capsule, 1–1.5 cm long, hairy, reddish. HABITAT/RANGE Native. Hammocks; Miami-Dade County,...

        • PITTOSPORACEAE: CHEESEWOOD FAMILY
          (pp. 469-469)

          Evergreen shrub or small tree, to about 12 m tall. BARK Gray or grayish brown, roughened by conspicuous horizontal lenticels. TWIG Stout with grayish, longitudinal lenticels. LEAF Alternate, rarely opposite, usually produced at the tips of branches and appearing whorled; leathery, simple, obovate, tip rounded, sometimes slightly notched; margins entire, rolled under. Upper surface lustrous, dark green or variegated creamy white and medium green; both surfaces hairy. Blade 4–9 cm long, 1.5–4 cm broad; petiole 12–20 mm long. FLOWER Bisexual, white, fading to yellow, fragrant, to about 2.5 cm diam.; petals 5. Spring. FRUIT Ovoid, angular, hairy,...

        • PLATANACEAE: PLANETREE FAMILY
          (pp. 470-471)

          The genus includes 7–10 species worldwide. Four species occur in North America, 3 native, 1 a horticultural hybrid; 2 are present in the East, 1 native.

          Usually large deciduous trees. BARK Smooth, eventually exfoliating in thin plates to reveal buff, creamy-white, or green inner bark, thus often appearing mottled. LEAF Alternate, simple, usually palmately or subpalmately veined and lobed (1 species pinnately veined), the margins entire or coarsely toothed. FLOWER Unisexual, male and female on the same plant, borne in rounded heads; usually wind-pollinated. FRUIT More or less linear achene subtended by long bristles and produced in dense, rounded,...

        • POLYGONACEAE: BUCKWHEAT FAMILY
          (pp. 472-473)

          About 120 species of tropical trees distributed in Mexico, Central and South America, the West Indies, and Fla. Evergreen, erect or spreading trees or shrubs. LEAF Alternate, simple, thin or leathery, stipule usually forming a sheath at the base of the petiole but often quickly deciduous. FLOWER Unisexual, male and female usually produced on separate plants, tiny, greenish or whitish; produced in a stalked, terminal spike or few-flowered cyme. FRUIT Achene, usually embedded in a fleshy perianth tube; oft en resembling a drupe.

          Evergreen tree, 10–20 m tall, to about 65 cm diam., usually smaller. Erect, single trunk, usually...

        • PROTEACEAE: PROTEA FAMILY
          (pp. 474-474)

          Evergreen tree, 10–25 m tall, to about 50 cm diam. in North America. Erect, single straight trunk; crown narrow, upright. BARK Gray, finely fissured with narrow ridges. LEAF Alternate, pinnately compound or simple and deeply incised, somewhat fernlike; leaflets or major divisions 7–19, usually connected by a narrow band of tissue along the midrib, opposite or alternate, 3–12 cm long, themselves usually divided into several narrow lobes. Upper surface dark olive green, lower surface silvery white, especially on new growth. Blade 15–33 cm long, to about 20 cm broad; petiole 4–6 cm long. FLOWER Bisexual,...

        • PUNICACEAE: POMEGRANATE FAMILY
          (pp. 475-475)

          Deciduous shrub or small tree, 2–8 m tall. Upright, often densely branched from the ground, sometimes with a single short trunk, branches sometimes spiny; crown rounded. BARK Brownish gray, thin, smooth, becoming slightly roughened. TWIG Angled at first, becoming round. LEAF Opposite and clustered, simple, lanceolate, elliptic, oblong, or oblanceolate; base narrowly wedge-shaped; tip bluntly pointed; margins entire. Upper surface lustrous green, hairless; lower surface paler. Blade 2–9 cm long, 1–2.5 cm broad; petiole 2–10 mm long. FLOWER Bisexual; sepals fused, forming a tube, calyx to about 2 cm long, fleshy, reddish; petals 5–9, red-orange,...

        • RHAMNACEAE: BUCKTHORN FAMILY
          (pp. 476-487)

          A genus of 20–30 species distributed in tropical and subtropical regions of Africa, s. Asia, Australia, the Pacific islands, South America, and North America.

          Deciduous or evergreen shrubs or trees. TWIG Lacks spines. LEAF Alternate, rarely opposite, simple, thin or leathery, toothed or not. FLOWER Bisexual; sepals usually 5, often fused; petals usually 5, often shorter than the sepals; stamens 5; central nectar-producing disk conspicuous, fleshy, green at first, turning yellow; the stigma becomes receptive after the stamens have dehisced and become reflexed. FRUIT Drupe or drupelike, 3-lobed, fleshy at first, becoming hard and capsule-like, splitting at maturity to...

        • RHIZOPHORACEAE: RED MANGROVE FAMILY
          (pp. 488-488)

          Evergreen large shrub or medium-size tree, 10–25 m tall, to 19 cm diam. Erect, contorted, with a single low-branching trunk that produces adventitious prop roots; crown spreading, often vertically flattened, the branches often twisted or contorted. BARK Smooth, reddish, becoming gray. TWIG Smooth, terminal bud covered by conspicuous stipules, 2.5–4 cm long. LEAF Opposite, simple, leathery, thick, elliptic tending toward obovate, base wedge-shaped, tip rounded or bluntly pointed, margins entire. Upper surface lustrous, dark green; lower surface pale green, covered with numerous tiny black dots. Blade 4–15 cm long, 2–6 cm broad; petiole to about 2...

        • ROSACEAE: ROSE FAMILY
          (pp. 489-561)

          Amelanchierincludes about 25 taxa distributed in North America, Europe, East Asia, and North Africa; as many as 20 species are reported for North America, all native. Members of the genus grow naturally on stream banks, river and lake shores, dry uplands, rocky and grassy slopes, mountainsides, bogs, wet thickets, swamps, and fields, 0–2,000 m. Serviceberries are usually easily identified to genus by the combination of distinctive dull green leaves with a comparatively long petiole, white flowers with narrow petals, and reddish, purplish, or blackish pomes. Discriminating among species within the genus is often difficult. Distinctions are slight, and...

        • RUBIACEAE: MADDER FAMILY
          (pp. 562-571)

          Deciduous, usually a shrub, occasionally a small tree, 3–15 m tall, to 30 cm diam. Erect, a single main trunk, rarely multiple; crown open, vase-shaped, spreading or ascending. BARK Smooth at first, becoming ridged, furrowed, and roughened. TWIG Reddish brown, usually hairy at first, becoming nearly hairless; decorated with corky lenticels, leaf scars U-shaped. LEAF Opposite or in whorls of 3 or 4 per node, simple, lanceolate or elliptic; base wedge-shaped or nearly rounded, rarely heart-shaped; tip abruptly long- or short-pointed. Upper surface lustrous, dark green; lower surface paler hairy or not, veins conspicuous. Blade 6–19 cm long,...

        • RUTACEAE: CITRUS OR RUE FAMILY
          (pp. 572-585)

          A genus of about 30 species of the American tropics and subtropics. The wood of these species is very resinous, burns easily and fragrantly, and has been used in the West Indies as a torch and in the fabrication of medicine and varnish.

          Evergreen shrub or rarely a small tree to about 7 m tall, 14 cm diam. Erect, single trunk or multiple, often low-branching; crown dense, branches ascending. BARK Smooth, brownish. TWIG Smooth, slender, hairless or sparsely hairy. LEAF Opposite, compound, turgid or somewhat drooping; blade to about 10 cm long, 10 cm broad; petiole 3–4 cm long,...

        • SALICACEAE: WILLOW FAMILY
          (pp. 586-617)

          Evergreen shrub or small tree, to about 5 m tall. Erect, rounded, or vase-shaped, single trunk or multiple; crown dense, with numerous branches. TWIG Slender, rounded. LEAF Alternate, simple, moderately leathery; elliptic, ovate, or obovate; base rounded or nearly heart-shaped; tip abruptly short-pointed or blunt; margins finely, evenly, and bluntly toothed, the teeth often gland-tipped. Upper surface lustrous, dark or medium green, midvein yellowish; lower surface paler. Blade 1.5–7 cm long, to about 3 cm broad; petiole 6–12 mm long, yellowish. FLOWER Bisexual, greenish yellow; sepals 4–6, fused, the calyx about 5 mm long; petals absent; produced...

        • SAPINDACEAE: SOAPBERRY FAMILY
          (pp. 618-646)

          A genus of about 130 species worldwide, encompassing nearly 100 subspecies and varieties. About 20 species occur in North America, 14 native; 15 occur in the East, 9 native.

          Deciduous, usually trees, a few shrubs. TWIG Lateral buds opposite; terminal and lateral buds usually with 2–8 pairs of overlapping scales, sometimes clamlike, with 2 opposite scales meeting at their margins. LEAF Opposite, usually unifoliolate and appearing simple, rarely compound (Boxelder), the margins usually lobed and sometimes toothed (a few species in China have unlobed leaves with entire margins), the lobes often sharp-pointed. FLOWER Unisexual, functionally unisexual, or bisexual, all...

        • SAPOTACEAE: SAPODILLA FAMILY
          (pp. 646-657)

          Evergreen shrub or small, delicate tree to about 15 m tall, about 58 cm diam. Erect, usually single straight trunk; crown oval or rounded, moderately dense. BARK Smooth, reddish brown. LEAF Alternate, simple, stiff; oval, ovate, or elliptic, base rounded, tip abruptly short-pointed, margins entire. Upper surface lustrous, dark green, hairless at maturity, lateral veins parallel and closely spaced; lower surface coppery brown from a covering of densely matted, feltlike coppery or rusty–brown hairs. Blade 1.5–13 cm long, 1–7 cm broad; petiole 8–12 mm long. FLOWER Bisexual; sepals 5, fused into a silky cuplike calyx less...

        • SCHOEPFIACEAE: SCHOEPFIA FAMILY
          (pp. 658-658)

          Evergreen shrub or small tree, to about 10 m tall. Erect, single stem or multiple; crown of crooked grayish branches. BARK Pale gray, smooth or slightly roughened. TWIG Smooth, zigzag, whitish. LEAF Alternate, simple, thick, leathery; ovate, elliptic, or broadly lanceolate, base wedge-shaped, tip abruptly pointed; margins entire, often wavy. Upper surface dull green, lower surface paler. Blade 3–7.5 cm long, 2–5 cm broad; petiole 3–8 mm long; exudes a strong aroma when crushed. FLOWER Bisexual, reddish or orange, sweetly fragrant, calyx with 4 or 5 lobes, corolla bell-shaped; petals 4 or 5, tips strongly recurved at...

        • SIMAROUBACEAE: QUASSIA FAMILY
          (pp. 659-660)

          Deciduous, often colony-forming tree, to about 25 m tall, 1 m diam. Erect, single straight trunk; crown dense, branches ascending and spreading. BARK Smooth, light or medium brown, developing whitish lenticels, eventually becoming shallowly vertically fissured, the furrows visible as pale, discontinuous lines. TWIG Stout, smooth, reddish brown, hairy at first, soon becoming hairless. LEAF Alternate, pinnately compound; blade 15–90 cm long, to about 30 cm broad; petiole 2–15 cm long. Leaflets opposite, sub-opposite, to slightly alternate, up to about 41 in number, each 2–15 cm long, 4–7 cm broad, lanceolate to broadly ovate, often curved...

        • SOLANACEAE: NIGHTSHADE FAMILY
          (pp. 661-664)

          This is a small genus of shrubs or small trees of 5–7 species native to South America; popular ornamental plants, several species have escaped or naturalized in North America. The trumpet-shaped flowers are pendent rather than erect.

          Shrub or small tree to about 5 m tall. Very similar to Angel’s-tears with larger flowers, 30–50 cm long, which open white but may turn peach or pink with age. HABITAT/RANGE Introduced from Ecuador. Cultivated in the Southeast; reported as naturalized in Ga.

          Evergreen or deciduous, semi-woody, large shrub or small tree, to about 5 m tall in tropical climes, dying...

        • STAPHYLEACEAE: BLADDERNUT FAMILY
          (pp. 665-665)

          Deciduous, usually a thicket-forming shrub spreading by underground runners, occasionally a small tree to about 8 m tall, 15 cm diam. Erect, single slender trunk; crown loosely branched, open. BARK Grayish green, smooth, usually with light creamy-white vertical stripes. TWIG Greenish, smooth, becoming reddish brown. LEAF Opposite, trifoliolately compound (rarely with 5 leaflets); leaflets 3–10 cm long, 2–5 cm broad, lateral leaflets stalkless, stalk of terminal leaflet 1.5–3 cm long; leaflet blade elliptic, base broadly wedge-shaped, tip abruptly short-pointed, margins finely and regularly toothed. Upper surface medium to dark green; lower surface paler, hairy. Blade to about...

        • STYRACACEAE: STORAX FAMILY
          (pp. 666-670)

          A genus of 2–4 species distributed in warm temperate regions of North America and Asia; 3 native species are treated here.Halesiais among a well-studied group of genera with East Asian-North American affinities.

          Deciduous shrubs or small trees. TWIG Pith diaphragmed, chambered between the partitions. LEAF Alternate, simple, more or less thin and papery to slightly thickened, margins entire or usually at least somewhat toothed. FLOWER Bisexual; sepals 4, distinct; petals 4, white, fused at least at the base, sometimes more extensively fused and forming a bell-shaped corolla; stamens 7–16, the filaments fused for about ⅓ their...

        • SYMPLOCACEAE: SWEETLEAF FAMILY
          (pp. 670-672)

          A genus of 318 species; 2 in the East, 1 native. Deciduous shrubs or trees. LEAF Alternate, simple, midvein on the lower surface usually prominent and sweet to the taste. FLOWER Bisexual, fragrant; sepals usually 5, overlapping; petals 5, overlapping, usually creamy white or yellowish. FRUIT Bluish or blue-black drupe, the remains of the calyx forming a crown at the apex.

          Deciduous, potentially semi-evergreen in southern parts of the range. Shrub or small tree, 2–15 m tall, to about 36 cm diam. Erect, usually single trunk; crown open, usually sparsely branched, branches commonly ascending. BARK Grayish with pinkish overtones,...

        • TAMARICACEAE: TAMARISK FAMILY
          (pp. 672-675)

          A genus of about 55 species, perhaps 9 in North America, 4 in the East. Deciduous shrubs or small trees, 2–12 m tall, with a distinctly redcedar-like appearance and usually a deep root system with a long taproot. Erect or upright, single low-branching trunk or multiple; crown with numerous ascending or spreading branches, appearing wispy. BARK Brownish or reddish brown, smooth at first, eventually becoming thick and furrowed. TWIG Red at first, becoming reddish brown. LEAF Alternate, scalelike, 1–7 mm long, grayish, covered with salt-excreting glands and often salt-encrusted; petiole absent. FLOWER Usually bisexual; if unisexual, male and...

        • THEACEAE: TEA FAMILY
          (pp. 676-679)

          Deciduous tree or shrub, 3–7 m tall, 10–25 cm diam. Erect or leaning, often with multiple trunks, sometimes with a single trunk; crown rounded. BARK Smooth, brown or reddish brown. LEAF Alternate, simple, obovate, with a long-tapering base; margins toothed, at least above mid-blade. Upper surface lustrous, dark green, veins conspicuous; lower surface paler. Blade 6–15 cm long, 4–5 cm broad; petiole absent or indistinct, winged and appearing as an extension of the blade. Turns an attractive red in autumn. FLOWER 7–10 cm diam.; sepals 5; petals 5, slightly joined at base, white, margins wrinkled;...

        • THEOPHRASTACEAE: JOEWOOD FAMILY
          (pp. 680-681)

          Jacquiniais a genus of about 13 species distributed in tropical portions of Mexico, the West Indies, Central and South America; 3 occur in the U.S., 1 native. The genusBonelliawas previously included withinJacquinia.

          Evergreen, typically a shrub, sometimes a small tree to about 6 m tall, to about 18 cm diam. Erect or upright, often contorted, single low-branching trunk or multiple trunks; crown open or dense. BARK Smooth, varying light gray to tan, thin. TWIG Gray, smooth, round in cross section, stout, often spotted with conspicuous scales. LEAF Alternate on lower parts of the branch, densely clustered...

        • ULMACEAE: ELM FAMILY
          (pp. 682-691)

          Deciduous tree, to 30 m tall, 1 m diam. Erect, single short, low-branching trunk; crown vase-shaped at first, becoming broad and rounded; branches ascending or spreading, purplish brown or brown. BARK Grayish white or grayish brown, with horizontal lenticels, exfoliating in plates revealing the orange inner bark. LEAF Alternate, simple, papery; elliptic or broadly lanceolate; base rounded or heart-shaped, slightly asymmetric; tip abruptly long-pointed; margins coarsely and bluntly toothed. Upper surface dark green, hairless; lower surface paler, sparsely hairy along the veins. Blade 3–10 cm long, 1.5–5 cm broad; petiole 2–6 mm long, hairy. FLOWER Unisexual or...

        • VERBENACEAE: VERVAIN FAMILY
          (pp. 692-696)

          Evergreen shrub or small, slender tree to about 12 m tall, 30 cm diam. Erect, single straight trunk; crown narrow, irregular. BARK Smooth, light reddish brown or gray, becoming scaly. TWIG Square in cross section. LEAF Opposite, simple, elliptic to obovate, leathery, thick; margins entire, rarely toothed on young branches. Upper surface lustrous green; lower surface yellow-green, dull, hairy, midvein tinted orange. Blade 5–17 cm long, 1–6 cm broad; petiole 1.5–2 cm long, orange or pinkish. FLOWER 9–12 mm long, white, tubular; petals 5, finely hairy; borne in an elongated raceme to 30 cm long. Year-round....

        • XIMENIACEAE: XIMENIA FAMILY
          (pp. 696-697)

          Evergreen shrub or small tree, usually 2–4 m tall, potentially to about 9 m. Erect, rambling, or scraggly, usually densely low-branched or with multiple trunks; crown irregular, with sprawling branches, the twigs oft en spine-tipped. BARK Grayish brown or reddish brown, smooth, often with visible lenticels. LEAF Alternate, simple, somewhat stiff and leathery; elliptic, ovate, oblanceolate, or nearly circular, often reflexed upward from the midrib; base broadly wedge-shaped or rounded; tip bluntly pointed or narrowly rounded, commonly with a tiny toothlike projection at the tip; margins entire. Upper surface dull or lustrous yellow-green, hairless. Blade 2.5–5 cm long,...

        • ZYGOPHYLLACEAE: CALTROP FAMILY
          (pp. 698-699)

          Evergreen large shrub or small tree to about 10 m tall, 20–45 cm diam. Young trees often strictly erect, with a single more or less straight trunk; older trees often produce multiple stems and low lateral branches, becoming irregular, diffuse, and somewhat gnarled; crown dense, spreading, usually rounded, often as wide or wider than the plant is tall; branch tips often drooping. BARK Pale gray or chalky white, deeply furrowed. TWIG Light gray, swollen at the nodes. LEAF Opposite, pinnately compound, blade 6–10 cm long, to about 6 cm broad; petiole to about 1 cm long. Leaflets 6–...

  5. ACKNOWLEDGMENTS
    (pp. 700-700)
  6. ABBREVIATIONS
    (pp. 701-701)
  7. GLOSSARY
    (pp. 702-706)
  8. INDEX OF SPECIES
    (pp. 707-720)