Flora of the Southeastern United States

1 Trees, shrubs, or woody vines.

  2 Prostrate or climbing woody vines (lianas), or sprawling shrubs.

    3 Leaf bases cordate, rounded, or truncate; leaves usually cordate, ovate, or deltoid shaped (occasionally hastate or broadly elliptic); corolla pale lilac colored; [non-native, se. US including FL; tribe Paederieae]

    3 Leaf bases cuneate to rounded but not cordate; leaves oblanceolate, lanceolate or linear; corolla white or yellow; [native, FL].

      4 Flowers and fruit sessile or subsessile; fruit yellow

      4 Flowers and fruit borne on pedicels or peduncles; fruit white

  2 Shrub or tree, plants upright.

        5 Inflorescence spherical or globular, in a tight round head; [collectively widespread].

          6 Inside of corolla glabrous; [waif, s. FL]

          6 Inside of corolla pubescent; [natives and non-native; widespread, including s. FL]

             7 Fruits dry, dehiscent, composed of nutlets; lobes of the corolla smaller; [subfamily Cinchonoideae; tribe Naucleeae]

             7 Fruits fleshy, indehiscent, composed of drupe-like syncarps; lobes of the corolla larger (inflorescence with 1 petaloid calycophyll in M. citrifolia); [subfamily Rubioideae; tribe Morindeae]

        5 Inflorescence cymose, thyrsoid, or corymbose (the inflorescence more open, not globular); [Coastal Plain, from s. SC southward].

               8 Plants with paired spines.

                 9 Corolla lobes 4; leaves to ca. 1 cm long; fruit ca. 5 mm long

                 9 Corolla lobes 5; leaves ca. 2-5 cm long ; fruit ca. 10 mm long

               8 Plants unarmed, not bearing spines or thorns.

                   10 Flowers orange-red; leaves usually whorled; [subfamily Cinchonoideae; tribe Hamelieae]

                   10 Flowers white, green, or maroon; leaves predominantly opposite.

                     11 Leaves linear, revolute, and strongly congested at branch tips; [FL keys southward]

                     11 Leaves broad, not linear, nor strongly congested (except sometimes in Guettarda); [widespread, including s. FL].

                       12 Flowers solitary, terminal, appearing Rose or Magnolia-like; [horticultural waif; subfamily Ixoroideae; tribe Gardenieae]

                       12 Flowers in cymose or thyrsoid inflorescences, not appearing Magnolia or Rose-like (sometimes singular in Exostema, but the corolla is conspicuously salverform); [natives, s. SC southward through FL]

                          13 Corolla salverform, the tube long and slender, ca. (1.5-) 2-9 cm long, the petals noticeably shorter than the tube (or if of similar length then the lobes linear, as in Exostema); [c. and s. FL only in our area].

                            14 Leaves ovate, elliptic, or lanceolate, not conspicuously rounded in shape (or at least this not predominant); corolla tube 2-5 cm long, the corolla lobes often recurved apically, linear and of similar length to corolla tube; stamens conspicuously exerted; [s. FL]

                            14 Leaves sub-orbicular to oval, conspicuously rounded in shape (the surfaces scabrous in G. scabra); corolla tube (1.5-) 2-9 cm long, the corolla lobes shorter than the corolla tube; [c. and s. FL]

                          13 Corolla not salverform (or if the tube somewhat lengthened not 2-5 cm long), the corolla lobes broadened and not typically recurved apically; stamens exerted or not; [s. SC southward through FL].

                              15 Inflorescences thyrsoid; calyx lobes inconspicuous; leaves evergreen; domatia present or absent in secondary abaxial vein axils; [of ne. FL southward].

                                16 Fruit large, fig-like (5-7 cm long berries), obovoid, green-colored when ripened and somewhat dull; [subfamily Ixoroideae; tribe Gardenieae]

                                16 Fruit smaller (pea-sized or smaller, ca. 4-6 mm in diameter), rounded and berry or drupe-like, white, red, or black colored when ripened, usually at least somewhat lustrous.

                                  17 Leaves with 8-14 pairs of prominently depressed secondary veins on the upper (adaxial) surface, the veins nearly arising perpindicular from the midvein and often curving (arcuate) toward the leaf margins (thus causing the leaf tissue to almost "rise" from between the veins), the blades herbaceous or membranous; fruit red; [subfamily Rubioideae; tribe Psychotrieae]

                                  17 Leaves usually with < 8 secondary veins, these not conspicuously depressed within the leaf blade (sometimes the midvein moderately depressed); the blades leathery; fruit black or white; [subfamily Cinchonoideae; tribe Chiococceae]

                                    18 Inflorescence elongate-thyrsoid, pedicels bent to one side, petals yellowish; ripened fruit white; plants often vine-like or sprawling shrubs

                                    18 Inflorescence cymose or corymbose, usually terminal, petals whitish; ripened fruit black; plants upright shrubs

1 Herbs (or creeping subshrubs in Mitchella); [ADD Borreria]

                                       19 Leaves whorled; [subfamily Rubioideae; tribe Rubieae]

                                       19 Leaves opposite.

                                         20 Fruit bright blue or purple, the apex bearing a partially persistent calyx; [waif, c. FL]

                                         20 Fruit variously colored but not bright blue to purple, the calyx not partially persistent or inconspicuously so; [widespread natives and non-natives].

                                           21 Flowers paired, the ovaries connate and developing into a single fleshy red fruit; leaves roundish; creeping subshrub; [subfamily Rubioideae; tribe Mitchelleae]

                                           21 Flowers single or in inflorescences with multiple flowers, the fruits either dry or fleshy and yellowish or black; leaves various; herb; [subfamily Rubioideae; tribe Spermacoceae].

                                             22 Carpels with few to many seeds.

                                               23 Corolla 5-lobed.

                                                 24 Flowers variously colored, often pinkish-purple or whitish-pink; leaf blades often > 5 cm long; plants perennial, erect, not succulent; [waif, c. and s. FL]

                                                 24 Flowers white; leaf blades < 5 cm long; plants annual, creeping or only partially erect, partially succulent; [uncommon exotic, SC s. to FL, w. to TX and AR]

                                               23 Corolla 4-lobed.

                                                    25 Leaf blades 1-5 mm long; plants conspicuously creeping

                                                    25 Leaf blades (3-) 5-50 mm long; plants erect, spreading, or prostrate.

                                                      26 Capsule longer than the calyx tube; flowers blue, pink, or white

                                                      26 Capsule not longer than the calyx tube; flowers white

                                             22 Carpels 1-seeded.

                                                        27 Flowers in dense, terminal, involucrate heads; flowers 4- or-6-lobed; styles 3

                                                        27 Flowers in axillary or terminal clusters, or single in axils, not involucrate; flowers 4-lobed; styles 2.

                                                          28 Flowers usually solitary in leaf axils; fruit separating into 2 parts.

                                                            29 Sepals 4 and similar in size; style entire; [of dry habitats]

                                                            29 Sepals 2 (or 4, and then markedly dimorphic); style cleft; [of moist to wet habitats]

                                                          28 Flowers in terminal and axillary clusters; fruits not separating into 2 parts.

                                                              30 Carpels opening transversely

                                                              30 Carpels opening longitudinally

1 Leaves deciduous (medium to pale green, thin in texture); leaves strictly opposite.

  2 Leaves 10-70 cm wide, cordate or subcordate at the base; flowers 5-merous, bilaterally symmetrical, large (20-70 mm long), the petals connate into a tube; fruit a capsule.

    3 Flowers white to yellow; capsules linear, >10× as long as wide; leaf undersurface with curly simple hairs; nectar glands present in the main vein axils on the undersurface of the leaf (visible from the underside or the upperside in fresh leaves and herbarium specimens as a triangle 1-4 mm on a side)

    3 Flowers lavender; capsules ellipsoid, < 2× as long as wide; leaf undersurface with branched (dendritic or stellate) hairs; nectar glands absent

  2 Leaves 1-12 cm wide, cuneate to rounded at the base; flowers 4-6-merous, radially symmetrical, small to medium (< 25 mm long), the petals either connate into a tube or separate and clawed; fruit a drupe or capsule.

      4 Leaves with prominently parallel-arcing secondary veins; corolla 4-merous, < 8 mm long, white to cream; inflorescence a many-flowered corymb or head; flowers white to cream; fruit a drupe

      4 Leaves with complexly branching secondary and tertiary veins; corolla 5-6-merous, 12-25 mm long, either greenish-yellow and mottled with purple, or white, pink, or purple; inflorescence a few-flowered cyme or many-flowered cymose panicle; fruit a capsule.

        5 Leaves 2.5-7 cm long, 1.5-4 cm wide; petals separate, clawed, 12-20 mm long (including the 6-9 mm long claw), white, pink, or purple; calyx remaining small and sepaloid (3.5-5 mm long); capsule 4-6-valved; [introduced, persistent from planting in upland to moist situations]

1 Leaves evergreen (dark green or gray-green, thick in texture); leaves opposite or subopposite (offset by < 2mm from the opposing leaf).

          6 Mangroves, with one of various adaptations to growing in tidal or near-tidal, saline situations: prominent salt-excreting glands on the petiole (Laguncularia in COMBRETACEAE), or prop roots (Rhizophora in RHIZOPHORACEAE), or abundant pneumatophores (Avicennia in ACANTHACEAE); [FL and less commonly subtropical shores of other, especially Gulf Coast, southeastern states].

             7 Leaves broadly elliptic, light green on both surfaces, rounded to broadly cuneate at the base, rounded and often retuse at the tip; petiole with 2 prominent salt-excreting glands; plants with neither prop-roots from the trunk and branches, nor pneumatophores from the roots

             7 Leaves narrowly elliptic, dark green above, cuneate at the base, acute to obtuse at the tip; petiole without salt glands; plants with either prop-roots from the trunk and branches, or pneumatophores from the roots.

               8 Plants with numerous pneumatophores ascending from the roots and terminating in a blunt tip; leaves gray on the undersurface

               8 Plants with prominent prop-roots descending to the ground from the trunk and branches; leaves light green on the undersurface

          6 Non-mangroves; [collectively widespread].

                 9 Secondary leaf veins relatively few (or diffuse), further branching and reticulating into the tertiary vein structure (or in Santalum and Strychnos the veins brochidodromous, arching away from and not completely reaching the margins of the blades); [collectively widespread].

                   10 Petioles prominently 2-ribbed; fruits drupeaceous, bearing an apical rimmed collar; [plants trees or shrubs, sometimes scrambling; uncommon non-native in s. FL]

                   10 Petioles not (or only scarsely) 2-ribbed; fruit a capsule, berry, or drupe (if a drupe, then not apically rimmed, as in OLEACEAE); [plants upright, natives and non-natives, collectively widespread].

                     11 Leaves strictly opposite, blue- or gray-green on both surfaces, suborbicular (about as wide as long), strongly aromatic when fresh

                     11 Leaves opposite or subopposite (offset by < 2mm from the opposing leaf); dark green above, pale green below; oblancolate, elliptic, or ovate (distinctly longer than wide), not aromatic when fresh

                       12 Twigs with spines; leaf venation with 3 primary veins from near the blade base; fruit a spherical berry, 5-12 cm long

                       12 Twigs lacking spines; leaf venation pinnate; fruit an elliptical drupe, < 2.5 cm long

                 9 Secondary leaf veins many and conspicuous, closely parallel to one another and extending unbranched to the leaf margin.

                          13 Leaves elliptic, widest near the midpoint of the blade, ca. 2× as long as wide; flowers in axillary thyrses; fruit a 1-seeded drupe, 2-4 cm long

                          13 Leaves spatulate, widest towards the broadly rounded tip, ca. 1.2-1.6× as long as wide; flowers terminal on the branches, 1-3; fruit a leathery capsule, (4-) 6-9 (-12)-valved, 5-8 cm long