2. Leaves tiny, scale-like, broadest at the base and more or less clasping the stem, <10 mm long and <1 mm wide...Tamarix
2. Leaves larger and broader, >40 mm long and >8 mm wide...3.
3. Pubescence of leaves including conspicuous stellate hairs (also with simple hairs) (best seen on lower leaf surfaces, and with at least 10x magnification); plants monoecious, the male flowers in yellow to brownish catkins, the female flowers solitary or in small spikes; fruit a nut in a cupule (an acorn)...Quercus
3. Pubescence of leaves absent or strictly of simple hairs; plants hermaphroditic (dioecious in Ilex in Aquifoliaceae); fruit various...4.
4. Flowers solitary, terminal, large (> 5 cm in diameter); pistils many, carpels separate; petals many (typically > 8); leaves mostly > 10 cm long (at least some on a branch longer than 10 cm); fruit an aggregate of follicles, each dehiscing along 1 suture; stipule scar circumferential at each node, encircling the twig...Magnolia
4. Flowers either in axillary racemes, panicles, umbels, fascicles, or solitary, or in terminal corymbs, umbels, or racemes, small (< 5 cm in diameter); pistil 1, with 1-8 fused carpels; petals 3-8; leaves mostly < 10 cm long (to 15 cm in Persea and to 30 cm long in Rhododendron); fruit either drupaceous, fleshy to dry, but not regularly dehiscent along sutures, or a capsule, dehiscing along 5 sutures; stipule scars absent, linear or triangular, not circumferentially encircling the twig...5.
5. Inflorescence terminal, a corymb, umbel, or raceme; fruit a capsule, dehiscing along 5 longitudinal sutures...6.
6. Capsules ovoid to globose or subglobose, about as long as broad, 5-8 mm long...Kalmia
6. Capsules elongate, > 2× as long as broad, 8-18 mm long...Rhododendron
5. Inflorescence axillary, a raceme, panicle, umbel, fascicle, or solitary; fruit drupaceous, fleshy to dry, but not regularly dehiscent along sutures...7.
7. Inflorescence an axillary raceme (with an elongate central axis, to which all flowers/fruits are attached)...8.
8. Fruit a dry, tan to brown, spherical or winged drupe; stamens 5 or 10; carpels 2-5; leaves oblanceolate (rarely narrowly elliptic), < 2.5 cm wide, the apex obtuse (more rarely acute, retuse, or rounded)...Cyrilla
8. Fruit a fleshy, black, spherical drupe; stamens 10; carpels 1; leaves elliptic, the apex acute to short-acuminate...Prunus
7. Inflorescence either an axillary umbel or fascicle (or reduced to solitary) or an axillary compound inflorescence (panicle or compound cyme), with 2-3 orders of branching...9.
9. Fruit a fleshy but not oily 4-8-seeded drupe; flowers 4-7-merous, with differentiated sepals and petals, the petals usually basally fused; fresh plants not strongly aromatic; inflorescence an axillary umbel or fascicle (or reduced to solitary), a central axis absent or < 1 cm long...Ilex
9. Fruit a fleshy and oily 1-seeded drupe; flowers 3-merous, with separate and undifferentiated perianth segments; fresh plants strongly aromatic; inflorescence compound, a panicle or compound cyme (with 2-3 orders of branching)...Persea
1. Leaves deciduous...10.
10. Leaf base deeply to shallowly cordate, with 3-7 palmate veins from the base; leaf blade about as wide as long or a little longer, mostly 0.9-1.3x as long as wide...11.
11. Juncture of petiole and leaf blade eglandular, but the uppermost 1-3 mm of the petiole swollen into a prominent upper pulvinus; corolla bilaterally symmetrical, with 5 petals, pink to purple (rarely white in some cultivars); flowers bisexual; fruit an oblong, flat legume, 6-10 cm long; main palmate leaf veins 5-7 (-9)...Cercis
11. Juncture of petiole and leaf blade with 2 red glands; corolla radially symmetrical, with 5-8 petals, white with red veins towards the base of the petals; flowers unisexual; fruit globose, 4-8 cm in diameter; main palmate leaf veins 3 (-5)...Vernicia
10. Leaf base cuneate, rounded, truncate, subcordate, or auriculate (with 2 small “earlobe-like” lobes at the base of the leaf blade), with 1 (mid) vein from the base (3 veins from the base in Celtis); leaf blade about as wide as long, or somewhat to much longer, 0.9-10x as long as wide...12.
12. Leaves 0.9-1.4x as long as wide...13.
13. Stipule scars circumferential, forming a line around the twig; flowers and aggregate fruits solitary, terminal...Magnolia
13. Stipule scars not circumferential (or not apparent); flowers and simple fruits in inflorescences of 1-many flowers, axillary or terminal, but not simultaneously solitary and terminal...14.
14. Leaf blade 3-6 cm long, 1-1.5x as long as the flexuous petiole...Triadica
14. Leaf blade 4-30 cm long, > 3x as long as the stiff petiole...15.
15. Hairs on foliage stellate (use at least 10x magnification), at least in part...16.
16. Fruit a nut in a cupule (an acorn); flowers unisexual, greenish or brownish, individually inconspicuous, the male flowers borne in catkins...Quercus
16. Fruit a dry, subglobose 3-valved capsule, with 1 seed; flowers bisexual, white, conspicuous...Styrax
15. Hairs on foliage simple or absent...17.
17. Petioles 1-5 (or more) cm long; leaves broadly orbicular, rounded at the base, usually rounded (rarely obtuse or nearly acute) at the apex, entire; fruit a fleshy drupe...Cotinus [Not yet known to be naturalized in North Carolina]
17. Petioles 1-2 cm long; leaves various in shape, often acuminate at the apex and/or cuneate at the base; fruit either a capsule or a berry...18.
18. Fruit a capsule; flowers 6-merous, petals distinctly clawed...Lagerstroemia
18. Fruit a berry; flowers 5-merous, petals fused...Vaccinium
12. Leaves >1.4x as long as wide...19.
19. Plants bearing nodal thorns; leaves elliptic to obovate, 3-9 cm long, 1-4 cm wide, 1.5-4x as long as wide; fruit a berry, black, 5-15 mm long, 5-seeded...Sideroxylon
19. Plants unarmed (except spiny in Maclura, but then the fruit a fleshy multiple, 80-120 mm in diameter); leaves various in shape, from broadest towards the base, near the middle, or towards the apex, 3-80 cm long, 1-30 cm wide, 1.5-10x as long as wide; fruit various...20.
20. Leaves distinctly widest near the base (at a point < 0.3x of the way from the base of the leaf blade to its apex), gradually long-tapering to an acuminate apex...21.
21. Fruit a spherical, dry drupe, 4-8 mm in diameter, with a single seed; leaf 1.5-6 cm wide...Celtis
21. Fruit a spherical, fleshy multiple, 80-120 mm in diameter; leaf 5-8 cm wide...Maclura
20. Leaves widest near the middle or towards the tip of the leaf blade (at a point > 0.4x of the way from the base of the leaf blade to its apex)...22.
22. Pubescence of the foliage stellate (at least in part; simple hairs sometimes present as well); flowers unisexual, the individual flowers inconspicuous, male flowers in catkins; fruit a nut in a cupule (an acorn)...Quercus
22. Pubescence of the foliage simple or absent (except sometimes stellate in Styracaceae); flowers bisexual, conspicuous, borne variously, but not in catkins; fruit various...23.
23. Leaf surface green (often somewhat paler green than the upper surface, but not whitened)...24.
24. Flowers solitary; ovary superior...25.
25. Flowers axillary, < 2 cm across, brown or maroon; perianth 3-merous, whorled; fresh foliage with a strong musky odor; fruit a fleshy berry; leaves cuneate at the base; twigs lacking circumferential stipule scars at each node...Asimina
25. Flowers terminal, > 4 cm across, white, pale yellow, or pink; perianth many-merous, spiraled; fresh foliage not noticeably aromatic; fruit an aggregate of follicles; leaves cuneate or auriculate at the base; twigs with circumferential stipule scars at each node...Magnolia
24. Flowers in inflorescences of several to many; ovary inferior (or superior in Cyrilla, Diospyros, and Lagerstroemia)...26.
26. Leaves with prominently parallel-arcing secondary veins; inflorescence a terminal corymb; leaves clustered at the tips of the twigs, often appearing pseudo-whorled; trichomes of the leaf undersurface predominantly 2-branched (some simple) (use at least 10x magnification); flowers 4-merous; fruit a blue drupe; small tree...Cornus
26. Leaves with secondary veins more obscure and complexly branching into tertiary veins; inflorescence axillary (often on the previous year’s wood), solitary to variously fascicled, clustered, or in racemes; leaves arrayed distichously along horizontal or arching twigs, not prominently clustered or pseudo-whorled (except often in Cyrilla and Nyssa); trichomes of the leaf undersurface either simple or stellate (or absent); flowers 4-5-6-merous; fruit a green, blue, or black drupe, an orange berry, or a green to brownish indehiscent capsule; small to large tree...27.
27. Flowers 4-5-merous; bark various, not as above...28.
28. Pubescence of foliage and other parts stellate (use at least 10x magnification); petals 4-5, white, 10-25 mm long; fruit dryish, indehiscent, either longitudinally 2-4-winged or not winged...27. [Styracaceae]
29. Corolla lobes 4; fruit elongate, winged, 2.5-5 cm long; petioles 15-25 mm long...Halesia
29. Corolla lobes 5; fruit globose, not winged, 0.5-0.9 cm in diameter; petioles 2-10 mm long...Styrax
28. Pubescence of foliage and other parts simple; petals either 0, or 4-5 and pink, white, or greenish-yellow, or 10 and greenish-yellow; fruit either a somewhat to very fleshy drupe or berry or a dry, brownish, spherical drupe, 2-2.5 mm in diameter...30.
30. Leaves evergreen or tardily deciduous, coriaceous...31.
31. Leaves spatulate or oblanceolate (to obovate); drupe dry, brownish, spherical, 2-2.5 mm in diameter...Cyrilla
31. Leaves obovate, elliptic, or ovate; berry fleshy, black, spherical, 5-8 mm in diameter...Vaccinium
30. Leaves promptly deciduous, herbaceous...32.
32. Fruit a spherical berry, 15-50 mm long, orange when ripe, subtended by the enlarged and persistent woody or leathery calyx; vascular bundles 1 per leaf scar; leaves never toothed; leaves whitish-green beneath; leaf midrib and upper petiole with tiny glands on their upper surfaces (reddish initially, then darkening) (use at least 10× magnification); leaves glabrate to tomentose with curly hairs beneath; female and male flowers on separate trees (dioecious); stamens 16; widest point of the leaf usually at the middle or below, the apex acute to acuminate...Diospyros
32. Fruit an ovoid or ellipsoid drupe, 8-30 (-40) mm long, blue-black, yellow, orange, or red when ripe; vascular bundles 3 per leaf scar; leaves sometimes bearing a few irregular teeth; leaves pale to medium green beneath; leaf midrib and upper petiole lacking reddish to dark glands on their upper surfaces; leaves glabrous or glabrate beneath; female and male flowers on the same tree (monoecious); stamens 5-12; widest point of the leaf usually beyond or at the middle, the apex obtuse to strikingly and abruptly acuminate...Nyssa
