Part 2

1. Leaves compound, with blades divided into leaflets 2 1. Leaves simple, blades not divided into leaflets 7 2. Leaves with opposite arrangement on twigs 3 2. Leaves with alternate arrangement on twigs 4 3. Leaflets with rounded bases, conspicuously whitish below when fresh; seed end of samara thickened, wing terminal only White Ash 3. Leaflets with wedge-shaped bases, green below; wing terminal and extending about half the length of the seed Green Ash 4. Buds valvate; buds, fruits, and lower surface of leaflets covered with yellow glandular scales; fruit winged on upper half of husk suture, husk thin, shell thin, meat bitter Bitternut Hickory 4. Buds imbricate, composed of overlapping scales 5 5. Leaflets typically 5, glabrous except for a few hairs on rachis and midribs; bark shaggy Shagbark Hickory 5. Leaflets 7 6 6. Leaflets densely tomentose; bark tight, in diamond-shaped pattern; husk very thick, shell thick, meat sweet Mockernut Hickory 6. Leaflets usually glabrous; bark tight, in diamond-shaped pattern; husk moderately thick, shell thick, meat sweet, husk tardily dehiscent Pignut Hickory 7. Leaves essentially evergreen, large percentage staying on trees until bud expansion, dark green above, silky white pubescent below; flowers white, about 5 to 8 cm in diameter Sweetbay 7. Leaves typically deciduous, or trees retaining some dead leaves to bud expansion 8 8. Leaf margins entire 9 8. Leaf margins lobed or toothed 12 9. Leaves with rusty pubescence below, broadly obovate, leathery bases tapering to cordate or cuneate Blackjack Oak 9. Leaves essentially glabrous or with a few hairs in vein axils 10 10. Leaves shiny below, elliptic or rhombic to spatulate Laurel Oak 10. Leaves dull green below 11 11. Leaves elliptic to obovate, strongly veined with purple spots and discoloration in summer; fruit a drupe Black Tupelo 11. Leaves abruptly obovate, bases wedge-shaped, few lateral veins; fruit an acorn Water Oak 12. Leaf margins toothed 13 12. Leaf margins lobed 16 13. Margins indistinctly toothed, blades narrowly to broadly ovate, base unequal, apex long acuminate Sugarberry 13. Margins distinctly toothed 14 14. Teeth obtuse or rounded, leaf base wedge-shaped, stellate pubescent below Chestnut Oak 14. Teeth sharp 15 15. Leaves normally elliptic, veins prominent below, bases rounded; corky outgrowths on older branches, often lacking on large trees Winged Elm 15. Leaves broadly oval, pinnate veins distinct, margins doubly toothed, bases oblique, unequally rounded American Elm 16. Leaves palmately lobed 17 16. Leaves pinnately or apically lobed 18 17. Leaves opposite, more or less glaucous and pubescent below; fruit a double samara Red Maple 17. Leaves alternate, glabrous below; fruit spherical, woody with spine-like projections; corky outgrowths on branches frequent Sweetgum 18. Blades truncate to notched at apex, 4-lobed; fruit an aggregate of samaras; flower conspicuous, greenish-yellow with red markings Yellow-poplar 18. Blades with acute to obtuse apices 19 19. Blades apically 3-lobed 20 19. Blades pinnately lobed 21 20. Blades broadly obovate, base rounded, rusty pubescent below Blackjack Oak 20. Blades narrowly obovate, base wedge-shaped, mostly glabrous Water Oak 21. Leaves with rounded lobes 22 21. Leaves with bristle tips to lobes and lateral teeth 23 22. Leaves with 7 to 9 lobes, divided nearly to the midrib, whitish below White Oak 22. Leaves with 5 unequal lobes, upper lateral pair larger, squarish, at right angles to midrib, crosslike in appearance, pubescent below Post Oak 23. Leaves pubescent below, whitish to tawny 24 23. Leaves glabrous below or with a few hairs on midrib and in vein axils 26 24. Leaves with 7 to 9 lobes, terminal lobes long, strap-shaped, slightly curved, bases bell-shaped Southern Red Oak 24. Leaves with 7 to 11 lobes 25 25. Leaves oblong, 7 to 11 lobes, base broadly wedge-shaped to truncate, secondary lobes rare; inner bark reddish Cherrybark Oak 25. Leaves broadly oval, 7 to 9 lobes, each lobe with secondary bristle-tipped teeth; inner bark yellow-orange Black Oak 26. Upper leaf surface glossy green 27 26. Upper leaf surface dull green, 7 to 9 lobes, 8 to 22 cm long, round sinuses extending less than half way to midrib Northern Red Oak 27. Leaves with 7 to 9 narrow lobes, sinuses extending more than halfway to midrib Scarlet Oak 27. Leaves with 5 to 7 narrow lobes, rounded sinuses, extending about three-fourths of way to midrib Shumard Oak

_Species Described and Illustrated_

Mockernut Hickory _Carya tomentosa_ Nutt.

Bark grayish, tight, marked with distinct diamond-shaped ridges and furrows. Branches stout, drooping to spreading and ascending. Twigs 10 to 12 mm in diameter, conspicuous leaf scars. Buds (terminal) 10 to 15 mm long, 5 to 8 mm in diameter, scales imbricate. Leaves alternate, deciduous, odd-pinnately compound, 20 to 40 cm long with 5 to 7 drooping leaflets; yellow hairs and glandular hairs on lower leaflet surface, apex acuminate, margin finely serrate, base obtuse, on very short petiolules. Flowers unisexual, appearing in spring with developing leaves, staminate in 3-parted drooping catkins, pistillate terminal on new growth. Fruit subglobose to obovate, 3 to 5 cm in diameter, husk 1 cm thick, slow to open, shell of nut thick and hard, meat sweet.

Pignut Hickory _Carya glabra_ (Mill.) Sweet

Bark light to dark gray, often blackish, rough and deeply furrowed. Branches stout, drooping to spreading. Twigs 3 to 5 mm in diameter, reddish brown, smooth. Buds ovoid, acute, glabrous, 8 to 12 mm long, scales imbricate. Leaves alternate, deciduous, odd-pinnately compound, 20 to 40 cm long, usually with 7 leaflets; upper pair and terminal largest, 10 to 15 cm long by 4 to 6 cm wide, broadly oval to slightly obovate. Flowers unisexual, staminate in 3-branched catkins appearing about the time of leaf maturity; pistillate terminal on new growth. Fruit oblong to obovoid to obpyriform, 30 mm in diameter by 35 mm long, husk about 3 mm thick, tardily dehiscent, shell of nut thick, meat sweet.

Shagbark Hickory _Carya ovata_ (Mill.) K. Koch

Bark smooth at first, then breaking into long, flat, irregular gray strips, to 5 mm thick, usually attached at the apex, free at the base. Branches stout, smooth, spreading to ascending. Twigs stout, orange-brown, leaf scars large. Buds (terminal), 10 to 20 mm long, 6 to 8 mm in diameter, scales imbricate. Leaves alternate, deciduous, odd-pinnately compound with 5 to 7 leaflets, usually 5 to 18 cm wide and 20 to 35 cm long; lateral leaflets ovate to ovate-lanceolate, terminal leaflet usually obovate, apices acute to acuminate, margins finely serrate, bases wedge-shaped, more or less yellow, pubescent below, gradually becoming glabrous with age. Flowers unisexual, appearing in spring with the developing leaves, staminate in 3-lobed catkins, pistillate on new growth. Fruits subglobose, 2.5 to 6 cm in diameter, husk 3 to 5 mm thick, shell of nut hard and moderately thin, meat sweet.

Bitternut Hickory _Carya cordiformis_ (Wangenh.) K. Koch

Bark brown to slate gray, smooth to lightly furrowed or with strongly interlaced ridges. Branches stiff, ascending, spreading. Twigs slender, glossy, often with yellow glands early in the season. Buds compressed, ovoid, 6 to 10 mm long, covered with yellow, valvate glandular scales. Leaves alternate, deciduous, odd-pinnately compound, 15 to 25 cm long with 7 to 9 leaflets, 7 to 15 cm long and 3 to 6 cm wide; lateral leaflets narrowly to broadly elliptic, terminal leaflet largest and usually obovate, apex acuminate, margin finely serrate, base wedge-shaped, with yellow glands on undersurfaces and on rachis. Flowers unisexual, staminate in 3-branched catkins appearing after leaves; pistillate terminal on new growth. Fruit ovate to subglobose, 2 to 3 cm in diameter, often slightly compressed, 4-winged on sutures from apex to middle of husk, husk thin, covered with yellow glandular scales, shell of nut thin, meat very bitter.

Southern Red Oak _Quercus falcata_ Michx.

Bark dark brown to grayish black, divided by shallow, irregular fissures into broad ridges. Branches stout, spreading to ascending. Twigs 2 to 5 mm in diameter, dull reddish brown. Buds ovoid, angulate 8 to 13 mm long, apex acute. Leaves alternate, deciduous, simple, many remaining as dead foliage until spring, ovate to obovate with bell-shaped base, 10 to 28 cm long, 7 to 30 cm wide; with 3 to 9 lobes and margins with deep rounded sinuses; when 3-lobed, central lobe strap-shaped and toothed near the apex and side lobes acute to acuminate, somewhat falcate; permanently pubescent below, white at first, turning rust. Flowers unisexual, staminate in tomentose catkins as leaves unfold; pistillate in leaf axils on twigs. Fruit an acorn, small, spherical to hemispherical; cup 12 to 15 mm wide, shallow saucer-shaped, enclosing about one-fourth to one-half of the nut; nut 8 to 12 mm long.

Cherrybark Oak _Quercus falcata_ var. _pagodaefolia_ Ell.

Bark dark gray to gray-black consisting of appressed scales in narrow flat ridges with shallow furrows. Branches stout, spreading to ascending. Twigs 2 to 4 mm in diameter, reddish, lightly fluted. Buds ovoid, 10 to 15 mm long, angled, scales pubescent with dark margins. Leaves alternate, tardily deciduous, persisting into December, simple, oval to oblong, 12 to 20 cm long, 7 to 8 cm wide; with 5 to 11 lobes, major lobes opposite each other, large rounded sinuses extending nearly to the midrib, margin entire with occasional bristle-tipped teeth near the apex of the lobes, dark green above, permanently pubescent below, sometimes thinly so, varying from white to rust color, especially on drying. Flowers as in _Q. falcata_. Fruit an acorn broader than tall; cups 12 to 15 mm wide; nut about 8 to 10 mm long, subglobose, flattened at base, rounded at apex.

Black Oak _Quercus velutina_ Lam.

Bark brownish-black on older trees, with thick, broad scaly ridges and deep furrows; inner bark yellow-orange—the only American oak with this feature. Branches stout, spreading to ascending. Twigs about 5 mm in diameter, reddish brown to dark brown, lightly fluted. Buds ovoid, 10 to 15 mm long, lateral buds sharply angled, scales ciliate, margin dark. Leaves alternate, deciduous, simple; membranous in seedlings and saplings to somewhat leathery in the middle to upper crown; lower leaves broadly elliptic to obovate, 15 to 30 cm long, 10 to 15 cm wide, entire to faintly lobed; middle-crown leaves 10 to 20 cm long, 10 to 15 cm wide, distinctly 5 to 9 lobed with broad rounded sinuses with apical bristles on each lobe; upper-crown leaves oblong to obovate, 8 to 20 cm long, 8 to 15 cm wide; dark shiny green above, yellow scurfy pubescence on young leaves of middle and upper crown, petioles 4 to 6 cm long, yellow to reddish. Flowers unisexual; staminate catkins 7 to 15 cm long; pistillate on short tomentose peduncles. Fruit an oval to obovoid acorn 10 to 25 mm long; cup cup-shaped to conical enclosing about one-half of the nut.

Scarlet Oak _Quercus coccinea_ Muenchh.

Bark dark grayish-black, divided into irregular fissures and scaly ridges. Branches stout, spreading to ascending. Twigs 3 to 4 mm in diameter, reddish, turning a dull red. Buds ovoid, acute, 5 to 7 mm long, covered with rounded, lightly pubescent scales. Leaves alternate, deciduous, simple; glabrous, except in axils of main veins on underside, oval to slightly obovate, 8 to 17 cm long, 5 to 13 cm wide, with 5 to 9 deep lobes often terminated by secondary lobes with bristle tips, sinuses usually deep, round, and wider than lobes; both surfaces pale green, upper surface shiny, bright scarlet in autumn, petioles about 4 cm long. Flowers unisexual; staminate in catkins with developing leaves; pistillate on pubescent peduncles. Fruit an acorn; cup 15 to 30 mm wide, covered with brown scales enclosing about one-third to one-half of the nut; nut ovoid, 10 to 20 mm long, occasionally with ring grooves near apical point at maturity.

Northern Red Oak _Quercus rubra_ L.

Bark dark brown, thick, divided by shallow furrows into long, flat-topped scaly ridges. Branches stout, spreading and ascending to form a round-topped crown. Twigs slender, reddish-brown to dark red. Buds ovate, acute, light brown, 8 to 10 mm long. Leaves alternate, deciduous, simple, oblong to oval to obovate, 12 to 22 cm long, 10 to 15 cm wide; 7 to 11 short lobes, lobes 3-toothed, bristle-tipped; upper surface dull green. Flowers unisexual; staminate in slender catkins appearing with the developing leaves, pistillate inconspicuous on last year’s wood. Fruit an acorn, 15 to 30 mm long; cup saucer-shaped, enclosing about one-fourth of the nut.

Shumard Oak _Quercus shumardii_ Buckl.

Bark dark gray to blackish, relatively smooth at first, then breaking into scaly ridges. Branches spreading to ascending. Twigs about 5 mm in diameter, olive green then turning dark reddish. Buds clustered at apex 5 to 7 mm long, sharp pointed, strongly angled. Leaves alternate, deciduous, simple; oval to slightly obovate, 10 to 20 cm long, 6 to 15 cm wide; with 7 to 10 bristle-tipped lobes, lobes on upper crown leaves narrower to slightly wider than sinuses, lobes on lower crown leaves wider than sinuses; dark green above, paler below, glabrous except for vein axils on lower surface; petiole about 5 cm long. Flowers unisexual; staminate in yellow catkins appearing with the unfolding leaves; pistillate on pubescent peduncles. Fruit an acorn; cup 20 to 31 mm across, enclosing about one-fourth of the nut; nut about 25 mm long, 15 mm in diameter.

Blackjack Oak _Quercus marilandica_ Muenchh.

Bark black, very rough, consisting of thick blocky plates. Branches stout, spreading to drooping. Twigs stout, about 5 mm in diameter. Buds with rusty brown hairs, about 4 to 8 mm long. Leaves alternate, tardily deciduous, simple, 7 to 25 cm long, broadly obovate at apex (bear-paw shape) tapering to a narrow base, margin entire or with 3 bristle-tipped apical lobes, upper surface dark green, rusty pubescent on undersurfaces. Flowers unisexual; staminate in catkins, appearing with the leaves; pistillate solitary or paired. Fruit an acorn, cup enclosing one-half to two-thirds of the nut; nut nearly ovoid, 20 to 25 mm long by 15 to 20 mm in diameter.

Laurel Oak _Quercus laurifolia_ Michx.

Bark nearly black, divided into broad flat ridges by deep fissures. Twigs 2 to 3 mm in diameter, usually reddish brown. Buds ovoid, reddish brown, 2 to 4 mm long. Leaves alternate, semi-deciduous, simple, a few shed in fall, a few persisting until spring; elliptic to spatulate, 7 to 15 cm long, 2 to 4 cm wide; apex acute or obtuse, margin entire, base cuneate; shiny green above, paler below; petioles 3 to 5 mm long, midrib conspicuous on underside. Flowers unisexual; staminate in catkins as leaves unfold; pistillate on twigs at leaf scars. Fruit an acorn, sessile to subsessile, cup 15 to 20 mm wide, enclosing about one-fourth of nut; nut hemispheric, rounded at apex and flattened at bottom, 15 mm long.

Water Oak _Quercus nigra_ L.

Bark smooth, grayish black, becoming scaly with age. Branches spreading to ascending, forming a round-topped crown in the open. Twigs 3 to 5 mm in diameter, gray. Buds ovoid, acute, reddish brown, 3 to 7 mm long. Leaves alternate, deciduous, simple; variable in shape and size, obovate to spatulate, 5 to 10 cm long, 2 to 5 cm wide; margin entire, wavy to distinctly lobed in juvenile specimens; sessile or with petiole to 1 cm long. Flowers unisexual; staminate catkins 5 to 8 cm long, pistillate catkins short-peduncled. Fruit an acorn about 15 mm wide, 10 mm high; cup thin, enclosing about one-fifth to one-third of the nut.

White Oak _Quercus alba_ L.

Bark light gray, separated by shallow furrows into flat ridges with loose appressed scales. Branches stout, drooping, spreading to ascending. Twigs 2 to 3 mm in diameter, reddish. Buds globose to ovoid, angulate, apex acute to obtuse, 3 to 5 mm. Leaves alternate, deciduous, simple, oblong to obovate, 7 to 20 cm long, 4 to 10 cm wide, with 7 to 11 uneven, rounded lobes and deep sinuses. Flowers unisexual, in catkins, preceding leaf expansion. Fruit an acorn, 15 to 35 mm long, 20 to 25 mm in diameter, cup 1.5 to 3 cm wide, usually cup-shaped, conspicuous with thickened scales, enclosing one-fourth to one-third of the nut.

Post Oak _Quercus stellata_ Wangenh.

Bark medium to dark gray, with deep furrows, scaly ridges. Branches stout, irregular, drooping to horizontal and ascending. Twigs 3 to 5 mm in diameter, gray to brownish. Buds broadly ovate, blunt to acute, 5 mm long, clustered at apex of twig. Leaves alternate, deciduous, simple; obovate, to 18 cm long, 5 to 10 cm wide; divided into 5 to 7 sinuate rounded lobes, the two lower lobes smaller than the upper pair, upper lobes and the terminal lobe resembling a cross, dark, shiny green above, grayish to brownish below, leathery. Flowers unisexual; staminate in catkins appearing with the unfolding leaves; pistillate on last year’s wood. Fruit an acorn, 13 to 25 mm long, 6 to 20 mm in diameter; cup hemispherical, enclosing about one-half of the nut, cup scales rusty-pubescent; nut ovate to ovate-oblong, about 15 mm long.

Chestnut Oak _Quercus prinus_ L.

Bark dark reddish brown to nearly black, deeply furrowed with narrow ridges. Branches stout, spreading to ascending. Twigs stout, angulate, smooth, purplish-green when new, turning orange or reddish-brown. Buds ovate-conical, somewhat angulate, 8 to 12 mm long, silky hairy. Leaves alternate, deciduous, simple; elliptic to obovate, 10 to 30 cm long, 3 to 8 cm wide; somewhat leathery, margin crenate with a vein ending in each rounded tooth, smooth green above, stellate-pubescent below. Flowers unisexual; staminate in catkins 5 to 10 cm long; pistillate in short spikes on stout peduncles. Fruit an acorn 25 to 35 mm long, 15 to 25 mm in diameter; cup vase-shaped, thin, rough with thickened scales, covering one-third to one-half of the nut.

Winged Elm _Ulmus alata_ Michx.

Bark dark, smooth at first becoming deeply furrowed on larger trees. Branches slender, ascending to spreading, corky ridges or wings on branches 3 years or older. Twigs about 2 mm in diameter, light green tinged with red. Buds sharp-pointed, divergent from twig 3 to 4 mm long. Leaves alternate, deciduous, simple; broadly ovate to elliptic, 4 to 8 cm long, 2 to 4 cm wide; apex acute to short-acuminate, margin doubly to triply serrate, base rounded; dull green above, lighter green below with prominent pinnate veins. Flowers perfect, abundant, tiny, opening just before leaves unfold, several in a cluster at a leaf scar, blooming late January into February. Fruit a samara, flat and elliptic, 6 to 8 mm long, margin ciliate.

American Elm _Ulmus americana_ L.

Bark gray to blackish, thick, divided into flat ridges by deep furrows. Branches ascending, arching, and spreading; open-grown trees vase-shaped in outline. Twigs 2 to 3 mm in diameter with 5 to 7 leaves which increase in size from basal to apical leaf, red-brown. Buds (leaf) brown, small, scaly, acute. Leaves alternate, deciduous, simple; broadly ovate, 5 to 15 cm long, 4 to 6 cm wide; apex acuminate, margin usually doubly serrate, base oblique on short petiole; upper surface smooth, marked with sunken veins pinnately arranged; veins more prominent on underside. Flowers perfect, buds greatly enlarge before opening; with very small flowers abundant in clusters; opening before the leaves expand, blooming from late December into February. Fruit a samara, oval to circular with wing surrounding the seed, about 10 mm in diameter, margin ciliate.

Sugarberry; hackberry _Celtis laevigata_ Willd.

Bark light gray to almost white, thin, smooth, usually more or less studded with irregular corky outgrowths. Branches spreading, slender. Twigs about 3 mm in diameter, reddish-brown. Buds about 3 mm long, alternate. Leaves alternate, deciduous, simple; narrowly elliptic to broadly ovate, 6 to 10 cm long, 2 to 4 cm wide; apex acute, margin usually entire, base broadly rounded or oblique. Flowers unisexual or perfect, tiny, inconspicuous, many staminate and few pistillate appearing on the new growth as the leaves unfold. Fruit a drupe with a bony reticulated nutlet, about 5 mm in diameter, orange-red on a pedicel often shorter than the petiole of the subtending leaf.

Yellow-poplar _Liriodendron tulipifera_ L.