1 Erect herbs; corollas purplish, red, or greenish.

1 Shrubs (erect or arching) or woody lianas; corollas white, yellow, red, or pink.

  2 Corolla 3-8 mm long, radially symmetrical or nearly so; ovary 4-locular

1 Leaves evergreen.

  2 Plant a shrub, erect, not requiring support.

    3 Leaves with spiny margins; fruit a drupe; [uncommon horticultural escapes].

      4 Flowers 5-merous, the petals clawed; leaves usually small (ca. 2-3 mm long or less); [FL]

      4 Flowers 4-merous; petals not clawed; leaves larger (the longer leaves usually > 3 mm long); [NC northeastward]

    3 Leaves with crenate or serrate margins (the teeth not bearing small spines); fruits various; [widespread natives and non-natives]

        5 Leaves slightly to strongly fleshy; inflorescence a head; [maritime situations]

        5 Leaves not fleshy; inflorescence either a head or otherwise; [collectively widespread].

          6 Leaves > 8 cm long, typically spotted with yellow, coarsely toothed; fruit a red drupe; [commonly cultivated, rarely seeding down nearby]

          6 Leaves < 8 cm long, not yellow-spotted, serrulate; fruit a capsule or purplish drupe; [plants native or cultivated].

             7 Inflorescence a head; [s. FL]

             7 Inflorescence otherwise; [more widespread].

               8 Corolla tubular, campanulate, bilaterally symmetrical; fruit a 1-seeded achene (rarely produced)

               8 Corolla radially symmetrical, with 4-5 distinct petals; fruit a 2-10-seeded capsule or drupe.

                 9 Fruit a 4-5-locular capsule, with 2 seeds per locule (though often fewer by abortion)

                 9 Fruit a (2-) 3-locular, purplish-black drupe, with (2-) 3 single-seeded stones

  2 Plant a subshrub, creeping shrub, or liana.

                   10 Leaves spinose-serrate; [exotics, rarely naturalized]

                   10 Leaves serrate (not spinose), serrulate, or crenate; [exotics and natives, collectively widespread].

                     11 Leaves slightly to strongly fleshy; inflorescence a head; [maritime situations]

                     11 Leaves not fleshy; inflorescence otherwise; [collectively widespread].

                       12 Leaves serrulate to serrate, the teeth uniformly around the margin or concentrated towards the tip; fruit dry, either indehiscent and 1-seeded or capsular and with several seeds.

                          13 Flowers 5-merous; petals fused; fruit indehiscent, 1-seeded; [montane, from e. TN, WV, and w. MD northwards in our area]

                          13 Flowers 4- or 5-merous; petals separate; fruit capsular, dehiscent, several-seeded; [collectively widespread in our area]

1 Leaves deciduous.

                            14 Leaves slightly to strongly fleshy; inflorescence a head, subtended by an involucre of phyllaries; [maritime situations]

                            14 Leaves not fleshy; inflorescence, flower, and fruit structure various, but not with the combination of features as above (sometimes the flowers in a head subtended by bracts, but then with other features differing, such as stamens 4, or green calyx present, or petals separate, or fruit a schizocarp of mericarps, etc.); [collectively widespread].

                              15 Lianas climbing by twining or by adventitious roots.

                                16 Stems with retrorse prickles; foliage scabrous

                                16 Stems not prickly; foliage smooth to variously hairy, but not scabrous.

                                  17 Leaves serrate, the teeth towards the leaf apex, the larger leaves > 4 cm wide; lianas climbing by adventitious roots; fruit a capsule; flowers 7-10-merous, with separate petals

                              15 Upright shrubs or trees, lacking any adaptations for climbing.

                                    18 Trees; leaves often a mix of alternate and opposite.

                                       19 Leaves harshly scabrous on the upper surface; fruit a multiple of achenes; leaf venation pinnate but irregular

                                       19 Leaves not scabrous; fruit a 2-4-seeded drupe; leaf venation neatly pinnate, the lateral veins nearly straight and parallel to one another

                                    18 Shrubs or trees; leaves strictly opposite (or often subopposite in RHAMNACEAE).

                                         20 Trees; leaves palmately-veined, with 5 or more veins from the base; [rarely naturalizing]

                                         20 Shrubs; leaves either triple-veined from near the base or pinnate-veined; [collectively widespread and common]

                                           21 Leaves strongly triple-veined from at or near the base of the blade, the 2 lateral veins arching towards the tip and rejoining the midvein or nearly so (becoming diffuse before rejoining); petals 4, white; stamens 15-90

                                           21 Leaves pinnate-veined; petals various, not both 4 and white (except sometimes in Hydrangea); stamens 1-15 (except 15-30 in Exochorda in ROSACEAE).

                                             22 Inflorescence head-like; flowers sympetalous and 4-lobed; fruit 2 seeded

                                             22 Inflorescence more diffuse, with internal axes and pedicels; flowers not BOTH sympetalous and 4-lobed (except in Forsythia and Buddleja, which have conspicuous axillary or paniculate inflorescences); fruit 1-seeded, 2-4-seeded, or 4-many-seeded.

                                               23 Plants in flower.

                                                 24 Corolla absent; flowers inconspicuous and small, in axillary fascicles or catkins.

                                                    25 Flowers in catkins; leaves usually a mix of opposite and alternate

                                                    25 Flowers in axillary fascicles; leaves strictly opposite (subopposite)

                                                 24 Corolla present; flowers larger, in terminal cymes, corymbs, racemes, panicles, or in axillary cymes or fascicles.

                                                      26 Petals separate; stamens 8-10 (-60) (or 4-6 in RHAMNACEAE and Euonymus in CELASTRACEAE).

                                                        27 Flowers 1-few, in axillary cymes; stamens 4-6; stems brown, tan, gray, or green.

                                                          28 Leaf venation pinnate, but irregular and reticulated; stems green

                                                          28 Leaf venation neatly pinnate, the lateral veins nearly straight and parallel to one another; stems brown, tan, or gray

                                                        27 Flowers 1 and terminal, or many, in terminal panicles or corymbs; stamens 8-10 (-60); stems brown, tan or gray.

                                                            29 Inflorescence a solitary, terminal flower; stamens 30-60

                                                            29 Inflorescence a terminal panicle or corymb; stamens 8-15

                                                      26 Petals fused, at least basally, and often strongly tubular; stamens 2, 4, or 5.

                                                              30 Stamens 5.

                                                                 31 Petals white, fused basally only, the lobes spreading

                                                              30 Stamens 2 or 4.

                                                                   32 Stamens 2; petals yellow; flowers radially symmetrical; inflorescence an axillary fascicle

                                                                   32 Stamens 4; petals white, pink, or lavender; flowers bilabiate; inflorescence a terminal thyrse or panicle or an axillary cyme.

                                                                     33 Petals 4; inflorescence a terminal thyrse

                                                                     33 Petals 5; inflorescence a terminal panicle or an axillary cyme.

                                                                       34 Inflorescence an axillary cyme

                                                                       34 Inflorescence a terminal panicle

                                                                         35 Flowers lavender; fruit a shiny orange drupe (appearing berry-like)

                                                                         35 Flowers pinkish-white; fruit a bristly achene

                                               23 Plants in fruit.

                                                                           36 Fruit a berry, drupe, or achene, indehiscent, fleshy at maturity (or dry in Kolkwitzia).

                                                                              37 Fruit a berry, with 20+ seeds

                                                                              37 Fruit a drupe or achene, with 1-4 seeds.

                                                                                38 Fruit an achene (1-seeded), dry at maturity

                                                                                38 Fruit a drupe (1-4-seeded), fleshy at maturity.

                                                                                  39 Inflorescence a terminal corymb

                                                                                  39 Inflorescence axillary, fascicled or a cyme.

                                                                                    40 Foliage with stellate hairs; fruit a pink-purple 4-seeded drupe

                                                                                    40 Foliage glabrous or with simple hairs; fruit a dark red, black, or blue 1-4-seeded drupe.

                                                                                      41 Fruit a 1-seeded drupe; [NC southwards and westwards]

                                                                                      41 Fruit a 2-4-seeded drupe; [widespread in our region]

                                                                           36 Fruit a capsule, dehiscent, dry at maturity.

                                                                                        42 Inflorescence a catkin, the flowers small (< 5 mm in diameter) and tightly arranged on the inflorescence axis (> 5 per cm of the axis)

                                                                                        42 Inflorescence various, but more diffuse, the flowers larger (> 5 mm in diameter, except for some flowers in Hydrangea in HYDRANGEACEAE) and loosely arranged (< 5 per cm of axis).

                                                                                           43 Capsule prominently 5-angled (star-shaped in ×-section)

                                                                                           43 Capsule not angled.

                                                                                             44 Inflorescence axillary, fascicled.

                                                                                               45 Capsule pink to red; fruits solitary or in axillary cymes

                                                                                               45 Capsule brown; fruits in axillary fascicles

                                                                                             44 Inflorescence terminal, a raceme, panicle, corymb, or compound cyme or thyrse.

                                                                                                 46 Inflorescence a flat-topped corymb or rounded compound cyme, as wide as or wider than long

                                                                                                 46 Inflorescence elongated, a raceme, panicle, or thyrse, much longer than wide.

                                                                                                   47 Capsule elongate (> 3× as long as wide), 8-25 mm long

                                                                                                   47 Capsule about as long as wide, 3-6 mm long.

                                                                                                     48 Sepal lobes 5

                                                                                                     48 Sepal lobes 4

1 Fresh plants with white, milky juice; pistils 2, united only by the style and stigma; fruit a pair of linear or fusiform follicles, 5-8× as long as thick (or longer), these variously shaped (terete, compressed, or prominently 3-angled)

1 Fresh plants with clear juice; pistil 1; fruit various, but not of paired, linear follicles.

  2 Liana (sometimes a partially scandent shrub) climbing by paired, recurved spines at the nodes; fruit an accessory fruit of a utricle embedded in a leathery expanded calyx

  2 Liana climbing by twining (occasionally forming shrub-like masses); fruit either a capsule (< 3× as long as wide), paired berries, drupeaceous (Petrea in VERBENACEAE), or a schizocarp of samaras (MALPIGHIACEAE).

    3 Flowers lavender; the showy calyx persisting well after petals fall; fruit drupe-like; [ornamental waif, c. and s. FL]

    3 Flowers not lavender, instead white, yellow, orange, or red; the calyx not showy and not persisting after the petals fall; fruit a capsule (Gelsemium), paired berries (Lonicera) or a schizocarp of samaras (MALPIGHIACEAE); [collectively widespread natives and non-natives].

      4 Petals clawed (the bases noticeably thinner than the broadened tips), the corolla not tubular; fruit a schizocarp of samaras; [uncommon non-natives, c. and s. FL; in part, Heteropterys, Hiptage, and Stigmaphyllon]

      4 Petals not clawed, of similar width from base to tip, the corolla tubular; fruit capsules (Gelsemium) or paired berries (Lonicera); [widespread natives and non-natives]

        5 Flowers bright yellow, radially symmetrical; leaves widest well below the middle, the apex acuminate; fruit a capsule