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Group 5: Woody angiosperms with alternate leaves
See list of 45 families in this group-
1a. Inflorescence a capitulum; fruit a cypsela (in part)
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1b. Inflorescence not pseudanthial; fruit various, but not a cypsela
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2a. Leaves compound
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3a. Perianth zygomorphic
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4a. Corolla usually papillionaceous; filaments connate, conspicuously so in most genera (distinct in Cladrastis), not seated on a nectar disk; fruit a legume (in part)
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4b. Corolla not papillionaceous; filaments distinct, seated on a nectar disk; fruit a bladdery-inflated, 3-valved capsule (in part)
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3b. Perianth actinomorphic
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5a. Leaves palmately compound
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6a. Leaflets retuse at the apex; sepals numbering 3 or 6, petaloid, purple brown; gynoecium of 3 distinct carpels (i.e., the flowers with 3 pistils)
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6b. Leaflets tapering to the apex; sepals numbering 5, sepaloid, green; gynoecium of 2–5 connate carpels (i.e., the flowers with 1 pistil)
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7a. Plants climbing by means of tendrils produced opposite the leaves, unarmed; inflorescence a panicle; ovary superior (in part)
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7b. Plants not climbing, armed with prickles; ultimate unit of inflorescence an umbel; ovary inferior (in part)
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5b. Leaves pinnately compound
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8a. Leaves twice pinnately compound (only once pinnately compound on spurs in Gleditsia); fruit a legume (in part)
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8b. Leaves once pinnately compound; fruit not a legume
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9a. Inflorescence a unisexual ament, the staminate drooping; flowers small, with an inconspicuous perianth; fruit a drupe with a fibrous exocarp and nut-like endocarp [Fig. 689]
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9b. Inflorescence not an ament, uni- or bisexual, none drooping; flowers with an evident perianth; fruit a fleshy drupe, samara, follicle, pome, or aggregate
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10a. Leaf blades punctate with pellucid dots; fruit a fleshy follicle, an orbicular samara, or a drupe (in part)
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10b. Leaf blades not punctate; fruit mainly otherwise, though a few genera with drupe fruits
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11a. Leaflets entire except for 1 or more coarse teeth near the base; fruit a samara
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11b. Leaflets toothed to lobed; fruit not a samara
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12a. Ultimate unit of the inflorescence an umbel; styles swollen at the base forming a stylopodium (in part)
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12b. Ultimate unit of the inflorescence not an umbel; styles without a stylopodium
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13a. Perianth monochlamydeous, only the sepals present; wood yellow (in part)
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13b. Perianth dichlamydeous, both sepals and petals present; wood not yellow
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14a. Flowers with a hypanthium, bisexual; plants with a watery sap; stems armed or unarmed (in part)
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14b. Flowers without a hypanthium, commonly unisexual; plants with a milky or watery sap (note: when watery, the sap poisonous); stems unarmed
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2b. Leaves simple
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15a. Plants lianas
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16a. Leaves with sheathing stipules; perianth segments with the midvein abaxially winged, especially in fruit; fruit a trigonous achene (in part)
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16b. Leaves exstipulate, or the stipules minute and caducous (e.g., Actinidiaceae) or evident in the Vitaceae, but these not sheathing the entire circumference of the stem; perianth segments lacking an evident, abaxial, longitudinal wing; fruit a berry, drupe, or capsule
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17a. Calyx gamosepalous, 3-lobed, with a strongly curved basal tube, petaloid [Fig. 50]; flowers with 6 stamens (in part)
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17b. Calyx gamosepalous, aposepalous, or obsolete, without a strongly curved tube, sepaloid; flowers with 5 or 12–100 stamens (when stamens are present)
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18a. Corolla gamopetalous; anthers dehiscing by terminal pores or clefts; some of the leaf blades with a distinct pair of small lobes or leaflets [Fig. 914] (in part)
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18b. Corolla apopetalous (cohering at the summit in Vitis); anthers dehiscing by longitudinal slits; leaf blades simple or lobed, the lobes, when present, not confined to the base of the blade
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19a. Leaf blades with peltate attachment of petioles; flowers with 6–9 petals and 12–24 stamens; fruit a drupe
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19b. Leaf blades with basal attachment of petioles; flowers with 5 petals and 5 or 18–100 stamens (when stamens are present); fruit a berry or capsule
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20a. Leaves palmately veined or palmately lobed [Fig. 942]; tendrils and inflorescences produced opposite the leaves; fruit a berry, white to blue or dark blue to black (rarely red or green) (in part)
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20b. Leaves pinnately veined; tendrils absent; inflorescences terminal or axillary; fruit a capsule or green-yellow berry
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21a. Stamens 5, the anthers basifixed; fruit an orange-yellow to orange capsule 6–13 mm long; pith continuous (in part)
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21b. Stamens 18–100, the anthers versatile; fruit a green-yellow berry 20–30 mm long; pith diaphragmed
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15b. Plants erect to mat-forming, but not climbing
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22a. Plants with a milky latex; fruit a multiple, usually fleshy (dry in Broussonetia) (in part)
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22b. Plants with a watery sap; fruit simple or aggregate, dry or fleshy
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23a. Stamens monadelphous; epicalyx of (6–) 8–15 bractlets present (in part)
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23b. Stamens distinct (connate for a short distance at the base in Halesia and cohered or connate in 2 species of Salix); epicalyx absent
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24a. Fruit a dark red to nearly black drupe with thin flesh on a peduncle (7–) 10–20 (–25) mm long; leaf blades asymmetrical at the base, usually strongly so, with 1 or both sides cordate (in part)
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24b. Fruit otherwise; leaf blades ± symmetrical or, less commonly, asymmetrical at the base, narrow-cuneate to cordate
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25a. Flowers unisexual
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26a. Leaves palmately 3- to 5-lobed; carpellate flowers in dense, spherical clusters; fruit a spherical aggregate of achenes or capsules
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27a. Bark exfoliating, creating a mottled pattern of colors; fruit an aggregate of narrow achenes; leaf blades with broad-triangular lobes that are coarsely and sparsely serrate
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27b. Bark not exfoliating; fruit an aggregate of capsules; leaf blades with narrow-triangular to triangular lobes that are finely and closely serrate
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26b. Leaves not palmately lobed (except in some 3-lobed leaves of Sassafras); flowers not in dense, spherical clusters; fruit otherwise
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28a. Plants up to 50 cm tall, with numerous, crowded leaves with linear to narrow-elliptic blades 3–8 mm long [Fig. 610]; fruit a dry or fleshy drupe (in part)
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28b. Plants usually taller, with larger, broader leaf blades; fruit various
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29a. Inflorescence an ament (the carpellate flowers solitary or in small clusters in the Fagaceae); perianth absent or tiny and inconspicuous
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30a. Winter buds either covered by a single, cap-like scale or with the lowest scale centered over the leaf scar; fruit a capsule, containing comose seeds
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30b. Winter buds with 2 or more scales, the lowest scale not centered over the leaf scar; fruit an achene, samara, or nut
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31a. Foliage with abundant, aromatic, yellow or brown resin glands; plants dioecious
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31b. Foliage eglandular or with relatively nonaromatic glands; plants monoecious
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32b. Ovary 2-locular; carpellate flowers commonly in aments; fruit an achene, samara, or nut
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29b. Inflorescence not an ament; perianth present, evident
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33a. Corolla of carpellate flowers (these usually with 8 sterile anthers) 15–20 mm long; perianth 4-merous; fruit a yellow-brown berry 20–40 mm long
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33b. Corolla 1–15 mm long; perianth 4- to 10-merous; fruit a red, yellow, silver, or blue to black drupe or berry 4–15 mm long
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34a. Pith diaphragmed; carpellate flowers epigynous; staminate flowers with 8–15 stamens (in part)
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34b. Pith continuous; carpellate flowers hypogynous or perigynous; staminate flowers with 4–9 stamens
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35a. Staminate flowers with 9 stamens; anthers dehiscing by uplifting valves; plants with aromatic foliage and wood
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35b. Staminate flowers with 4–8 stamens; anthers dehiscing by longitudinal slits; plants without aromatic foliage and wood
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36a. Ovary with 2–4 stigmas, the style 2- to 4-lobed; stamens antepetalous (in part)
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36b. Ovary with 1 stigma, the style unbranched; stamens antesepalous
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37a. Leaf blades and branchlets with abundant silver scales; plants sometimes armed with thorns; petals absent [Fig. 605]; styles elongate (in part)
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37b. Leaves and branchlets not lepidote; plants unarmed; petals present; styles very short, nearly absent (in part)
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25b. Flowers bisexual
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38a. Leaf blades entire, with abundant silver scales; plants sometimes armed with thorns (in part)
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38b. Leaf blades entire, toothed, or lobed, not lepidote; plants unarmed or armed
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39a. Corolla zygomorphic; fruit a legume (in part)
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39b. Corolla (or petaloid portions of flower) actinomorphic; fruit not a legume
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40a. Corolla of 4 yellow, linear petals; plants flowering in the fall during and after the falling of the leaves
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40b. Corolla of 4–10 variously colored petals or petal-like members (petaloid hypanthium in Dirca), the petals not strap-shaped with parallel margins; plants flowering prior to leaf fall
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41a. Fruit an elliptic to suborbicular samara (fruit unwinged in Ulmus parvifolia); flowers tiny, anemophilous, precocious (serotinous in Ulmus parvifolia); leaf blades double-serrate in most species
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41b. Fruit not a samara; flowers variously pollinated, generally entomophilous, precocious to serotinous; leaf blades entire, serrate, or lobed
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42a. Peduncle of the inflorescence adnate to a conspicuous, elongate bract; the numerous stamens commonly connate into 5 antepetalous groups (in part)
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42b. Peduncle of the inflorescence without bracts or, when bracteate, free from the bract; stamens 4–many, distinct (shortly connate at the base in Halesia, but that species with 4-merous, gamopetalous flowers)
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43a. Pith diaphragmed; gynoecium composed of a single carpel (very rarely 2 carpels) (in part)
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43b. Pith continuous; gynoecium composed of 1–66 (–73) carpels
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44a. Gynoecium with (9–) 19–66 (–73) carpels [Fig. 52]; androecium with laminar filaments; fruit an aggregate of samaras or an agreggate of follicles that each bear a large seed covered by a pink to red or red-orange aril
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44b. Gynoecium with 1–10 carpels; androecium usually with slender filaments; fruit otherwise, usually a drupe, berry, pome, achene, capsule, or aggregate (when an aggregate, as in some Rosaceae, usually with fleshy carpels)
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45a. Perianth monochlamydeous
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46a. Flowers with a conspicuous hypanthial tube, the petaloid members yellow or pink to purple (rarely white); stamens 8
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46b. Flowers with a short, inconspicuous hypanthial tube, or lacking one altogether, petaloid members absent or white; stamens 4 or 5
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47a. Stamens antepetalous; leaves commonly subopposite; branches often ending in a short, spine-like process (in part)
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47b. Stamens antesepalous; leaves alternate; branches without spines (in part)
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45b. Perianth composed of 2 or more whorls, both the sepals and petals present
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48a. Flowers perigynous or epigynous
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49a. Stamens numbering more than the petals [Fig. 852]
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50a. Stamens numbering more than 10, more than twice as many as the petals
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51a. Stamens adnate to the base of the corolla; calyx light yellow, the lobes 1–1.5 mm long, ciliate on the margins; ovary epigynous; fruit a blue (rarely white) drupe 3–8 mm long
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51b. Stamens not inserted at the base of the corolla; calyx otherwise; ovary perigynous in flower (but becoming epigynous in fruit in some species); fruit not as above (in part)
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50b. Stamens numbering 10 or fewer, up to twice as many as the petals
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52a. Stamens numbering 8, the filaments shortly connate at the base and distinct above; fruit 4-winged, dry, 1- to 3-seeded; flowers with 1 style
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52b. Stamens 5–10, the filaments not monadelphous at the base; fruit otherwise; flowers with 2–5 styles (in part)
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49b. Stamens as many as the petals [Fig. 676]
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53a. Ovary inferior [Fig. 675]
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54a. Plants with broad-based prickles along the stems and branches; inflorescence a corymb-like panicle of umbels (in part)
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54b. Plants unarmed or with bristles or thin prickles; inflorescence a raceme or corymb (rarely a solitary flower)
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53b. Ovary superior (at least in flower)
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55a. Plants usually armed with stout thorns; stamens antesepalous [Fig. 837] (in part)
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55b. Plants unarmed or with a slender, spine-like process at the apex of some branches; stamens antepetalous (in part)
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48b. Flowers hypogynous
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56a. Plants armed with spines [Fig. 479]; perianth composed of 6 sepals in 2 cycles and 6 petals in 2 cycles; anthers dehiscing by uplifting valves (in part)
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56b. Plants unarmed or with thorns in Lycium; perianth composed of fewer parts; anthers dehiscing by longitudinal slits or apical pores
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57b. Sepals monomorphic; petals white, pink, red, purple, green, or green-white
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58a. Stamens numbering the same as the petals and antepetalous, often enclosed by the petals (especially in bud), or the petals absent and the stamens alternating with the sepals (in part)
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58b. Stamens fewer than, as many as, or more than the petals, alternating with the petals, not enclosed by the petals (recessed in pouches in the corolla in Kalmia)
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59a. Stamens fewer than or as many as the petals or inner tepals
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60a. Ovary 2-locular; fruit a red berry 10–20 mm in diameter; plants usually with thorns (in part)
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60b. Ovary 3- to 8-locular; fruit otherwise; plants unarmed
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61a. Androecium of 4 stamens seated on a lobed, nectary disk; leaf blades 3–5 mm long, scale-like, subampexicaul; perianth 4-merous, with a corolla shorter than 2 mm
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61b. Androecium of 5–10 stamens (only 4 in some Ilex), not seated on a conspicuous nectar disk; leaf blades various, though usually longer and/or with a petiole; perianth mostly 5-merous, infrequently only 4-merous, the corolla longer than 2 mm
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62a. Styles short, the stigma nearly sessile on the summit of the ovary; sepals present, though small and inconspicuous (in part)
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62b. Styles elongate, the stigma elevated above the summit of the ovary; sepals usually evident (in part)
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59b. Stamens numbering more than the petals
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63a. Plants evidently pubescent with compound hairs; ovary 3-locular; leaf blades with plane margins, deciduous
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63b. Plants glabrous or with simple hairs; ovary 2- to 9-locular; leaf blades sometimes with revolute margins and/or evergreen (in part)
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Each photo represents one family in this group.