1 Fruit a fleshy drupe; plant a small tree, shrub, or sprawling vine; mature stems terete or obscurely 4-sided (by secondary growth).

  2 Flowers zygomorphic; palmately (3-) 5-7 (-9) foliolate or simple (V. rotundifolia); [subfamily Viticoideae]

  2 Flowers essentially actinomorphic; leaves simple.

    3 Stems pubescent with dendritic hairs; inflorescence axillary; calyx 0.5-2 mm, lobes diminutive to nearly obsolete

    3 Stems glabrous or pubescent with simple (unbranched) hairs; inflorescence terminal (rarely only axillary); calyx lobes conspicuous or diminuitive.

      4 Corolla 5-40 mm long; calyx 5-18 mm, the lobes conspicuous, the calyx length often surpassing the fruit when mature; [subfamily Ajugoideae]

      4 Corolla 2-5 mm long; the calyx lobes inconspicuous and not surpassing the mature fruit; [subfamily Premnoideae]

1 Fruit a schizocarp of 4 dry mericarps; plant either an herb or a shrub to 5 (-20) dm tall; mature stems usually distinctly 4-sided (sometimes terete or obscurely 4-sided).

        5 Calyx with either a distinctly enlarged protuberance on the upper surface, or the upper lobe expanded and “cap-like”.

          6 Calyx with 5 lobes, clearly separate apically, with the upper lobe expanded and “cap-like”

          6 Calyx with 2 entire lobes joined at the margins, rounded apically, with a distinct protuberance on the upper surface

        5 Calyx without an enlarged protuberance or “cap-like” upper lobe.

             7 Upper lip of corolla greatly reduced or lobes laterally disposed, thus the corolla appearing to consist of one large lower lip; [subfamily Ajugoideae].

               8 Lower lip with 2-4 lobes; flowers yellow or deep blue-purple; plants stoloniferous

               8 Lower lip appearing 5-lobed (proximal 2 lateral, erect lobes represent the cryptic upper lip); flowers white to pink; plants cespitose

             7 Upper lip of corolla conspicuous, flaring or galeate.

                 9 Plants distinctly repent and rooting at the nodes, or producing elongate stolons.

                   10 Plants repent.

                     11 Herbs; leaves cordate-reniform, coarsely crenate, the blade > 1 cm long; inflorescence of axillary cymules; corollas 10-20 mm

                     11 Subshrubs; leaves ovate to elliptic, entire, the blade < 1 cm long; inflorescence a terminal thyrse; corollas 4-5 mm

                   10 Plants stoloniferous.

                       12 Inflorescence in dense axillary verticils; calyx and corolla actinomorphic, calyx 4-5-lobed, flowers 3-4 mm long

                       12 Inflorescence terminal; calyx and corolla zygomorphic, calyx 5-lobed, flowers 20-30 mm long

                 9 Plants not distinctly repent or stoloniferous.

                          13 Calyx with 6-10 lobes or teeth.

                            14 Calyx zygomorphic, canescent with simple trichomes, spinose lobe tips straight

                            14 Calyx actinomorphic or essentially so, densely pubescent with stellate hairs, spinose lobe tips uncinate

                          13 Calyx with 5 or fewer lobes or teeth.

                              15 Calyx with 3-4 prominent lobes (rarely 5, if one includes small teeth).

                                16 Calyx and corolla essentially actinomorphic

                                16 Calyx and corolla zygomorphic.

                                  17 Calyx with 4 unequal primary lobes; flowers large, 2.5-3.5 cm long, in bracteate terminal racemes

                                  17 Calyx with 3 primary lobes (upper lobe occasionally with 3 apiculate teeth, e.g. Salvia lyrata); flowers 3 cm or less, in terminal thyrses.

                                    18 Stamens 4; calyx enveloped and partially concealed by subtending bracts

                                    18 Stamens 2; calyx not enveloped by subtending bracts.

                                       19 Shrubs; calyx with simple and dendritic hairs; leaves revolute, coriaceous

                              15 Calyx usually with 5 prominent lobes (except for Clinopodium with rarely fused upper lobes).

                                         20 Fertile stamens 0-2.

                                           21 Calyx actinomorphic or essentially so; corollas actinomorphic or zygomorphic.

                                             22 Corolla actinomorphic, lobes spreading and nearly equal (one lobe slightly emarginate and/or enlarged).

                                               23 Inflorescences axillary; foliage not or faintly aromatic

                                               23 Inflorescences terminal; foliage strongly aromatic

                                             22 Corolla zygomorphic (bilabiate).

                                                 24 Inflorescence in loose terminal and axillary cymules; corollas not galeate or arching

                                                 24 Inflorescence densely capitate (often also axillary); corollas strongly galeate, arching

                                           21 Calyx and corollas clearly zygomorphic.

                                                    25 Corolla 7-20 mm; inflorescence a densely clustered terminal or axillary cyme, or a well developed panicle.

                                                      26 Inflorescence a dense cluster of one or more terminal cymules (occasionally just axillary); lower lip of corolla not fringed

                                                      26 Inflorescence a panicle; lower lip of corolla conspicuously fringed

                                                    25 Corolla ca. 3-10 mm long; inflorescence a loose axillary cyme or slender terminal spike or spike-like panicle.

                                                        27 Corolla 3.5-4 mm, borne 2 per node in a slender terminal spike; middle lobe of upper calyx reduced

                                                        27 Corolla 4-10 mm, borne in axillary cymes or spike-like panicle; upper calyx lobes similar.

                                                          28 Flowers in loose axillary cymes; calyx gibbous, throat closed by hairs; corollas ca. 4-5 mm long

                                                          28 Flowers in a spike-like panicle; calyx not gibbous or closed by hairs; corollas ca. 10 mm long

                                         20 Fertile stamens 4.

                                                            29 Stamens ascending under the upper corolla lip, either included within the tube (or at least not clearly exserted beyond it).

                                                              30 Calyx actinomorphic.

                                                                 31 Flowers borne in terminal verticils or thyrses, with reduced bracteal leaves.

                                                                   32 Calyx 15-nerved; verticils tightly aggregated

                                                                   32 Calyx 5-10-nerved; verticils well spaced

                                                                 31 Flowers borne in axils of well-developed leaves, or a terminal raceme with 1 flower per node.

                                                                     33 Calyx lobes with thickened spinescent apices.

                                                                       34 Stems often with swollen nodes (areas just below appear dark and sunken upon drying, except G. ladanum); hairs of the stem either exclusively hispid or short recurved and mixed with longer glandular trichomes; corolla 15-28 mm long

                                                                       34 Stems without swollen nodes; hairs of the stem finely and softly retrorse, generally lacking glandular hairs (though sessile glands may be present); corolla 5-14 mm long.

                                                                         35 Corolla 5-7 mm long, not much longer than the calyx, weakly bilabiate and lacking an annulus

                                                                         35 Corolla 8-14 mm long and well-exceeding the calyx, strongly galeate and annulate

                                                                     33 Calyx lobes without spinescent apices (although lobes may be pointed or acute).

                                                                           36 Flowers in terminal racemes, corolla tube broadly inflated

                                                                           36 Flowers borne in axils of well developed leaves, corolla tube not broadly inflated.

                                                                              37 Verticils 2-6-flowered, loose; corollas 5-7 mm

                                                                              37 Verticils 6-12-flowered, compact; corollas 10-30 mm.

                                                                                38 Corolla 10-15 mm long; calyx with 10+ nerves

                                                                                38 Corolla 10-30 mm long; calyx 5-nerved

                                                              30 Calyx zygomorphic.

                                                                                  39 Shrubs, diffusely branched; [restricted to se. Coastal Plain and Cumberland Plateau]

                                                                                  39 Herbs, branched or unbranched; [collectively widespread].

                                                                                    40 Calyx teeth distinctly white or pink, noticeably different from the tube

                                                                                    40 Calyx teeth coloration not noticeably different from the tube.

                                                                                      41 Flowers 1 per bracteal axil.

                                                                                        42 Corolla nearly regular, 4-6 mm long.

                                                                                        42 Corolla bilabiate, >10 mm long

                                                                                      41 Flowers 2-many per bract or leaf axil.

                                                                                           43 Plants lemon-scented, flowers in the axils of well-developed leaves

                                                                                           43 Plants mint-scented or non-aromatic, flowers terminal and/or axillary.

                                                                                             44 Upper median calyx lobe longer and wider than the other 4; flowers terminal

                                                                                             44 Upper lobes differing in sinus depth and/or size from the lower lobes; flowers borne variously.

                                                                                               45 Bracts broadly rounded, apiculate or absent.

                                                                                                 46 Bracts broadly rounded, apiculate; inflorescence terminal

                                                                                                 46 Bracts wanting; inflorescence axillary

                                                                                               45 Bracts setaceous or elliptic, but not broadly rounded or apiculate, present.

                                                                                                   47 Calyx clearly bilabiate; corollas 7-15 mm long

                                                                                                   47 Calyx scarcely bilabiate; corollas 5-7 mm long

                                                            29 Stamens (at least some) well exserted beyond the upper corolla lobe.

                                                                                                     48 Lower lip of corolla distinctly fringed

                                                                                                     48 Lower lip of corolla not fringed.

                                                                                                        49 Calyx zygomorphic.

                                                                                                          50 Flowers in dense terminal capitate clusters, subtended by large bracteal leaves (these often whitened on the upper surface and especially towards the base)

                                                                                                          50 Flowers borne otherwise.

                                                                                                            51 Flowers borne in few-flowered cymose axillary clusters, overall appearing paniculate; [subfamily Ajugoideae]

                                                                                                            51 Flowers borne in a spike-like terminal thyrse.

                                                                                                              52 Corolla pink to lavender or white, 11-17 mm long

                                                                                                              52 Corolla blue (rarely white), 7-12 mm long

                                                                                                        49 Calyx actinomorphic.

                                                                                                                53 Flowers borne in a dense terminal spike, 2-3-verticilled globose head, or spiciform thryse.

                                                                                                                  54 Inflorescence secund

                                                                                                                  54 Inflorescence terete.

                                                                                                                     55 Small plants to ca. 30 cm; leaves short, sessile, linear- lanceolate with revolute, entire margins; [endemic to FL and se. GA]

                                                                                                                     55 Large plants, well over 30 cm tall; leaves often petiolate, broadly ovate or lanceolate, margins not revolute or entire; [collectively widespread].

                                                                                                                       56 Bracts broadly rounded; corolla distinctly bilabiate; plants 1-3 m tall

                                                                                                                       56 Bracts linear-lanceolate; corolla nearly regular; plants < 1 m tall

                                                                                                                53 Flowers borne in axillary verticils or terminal (capitate to loosely flowered) clusters.

                                                                                                                         57 Flowers in axillary clusters, corolla nearly regular.

                                                                                                                           58 Axillary clusters loose, 1-3-flowered; [subfamily Ajugoideae]

                                                                                                                           58 Axillary clusters dense, many-flowered; corolla white-pink

                                                                                                                             59 Stems scabrous; corolla mostly blue-violet

                                                                                                                             59 Stems glabrous to pubescent; corolla mostly white-pink

                                                                                                                         57 Flowers in densely capitate or loosely flowered terminal clusters, corolla distinctly bilabiate.

                                                                                                                               60 Flowers in loosely branched terminal and axillary cymes

                                                                                                                               60 Flowers densely capitate cluster or terminal spike of well spaced verticils.

                                                                                                                                  61 Inflorescence either capitate or a spike, not subtended by large bracteal leaves

                                                                                                                                  61 Inflorescence capitate, subtended by large bracteal leaves (these often whitened on the upper surface and especially towards the base)

1 Inflorescence an involucrate head subtended by phyllaries, the heads solitary or many and variously arrayed in secondary inflorescences, the ovary inferior, the corolla connate and tubular at least basally, the calyx absent, the stamens 5, the fruit a cypsela

1 Inflorescence, flower, and fruit structure various, but not with the combination of features as above (sometimes the flowers in a head subtended by bracts, e.g. Eryngium in APIACEAE, but then with other features differing, such as stamens 4, or green calyx present, or petals separate, or fruit a schizocarp of mericarps, etc.).

  2 Basal leaves 2-lobed, pinnately lobed, or palmately lobed (not considering cordate, hastate, or auriculate leaf bases as “lobed”).

    3 Basal leaves 2-lobed, hinged between the lobes, each lobe with stiff, marginal, eyelash-like bristles; [Coastal Plain of NC and SC, rarely planted and weakly naturalized elsewhere]

    3 Basal leaves 3-many-lobed, palmately or pinnately; [collectively widespread].

      4 Leaf lobing pinnate.

        5 Gynoecium of separate pistils (each with a single carpel); fruit an aggregate

        5 Gynoecium of a single pistil (with 2, rarely more, carpels); fruit simple.

          6 Stamens many; sepals 2, petals 4; fresh plants with yellow, orange, or white milky juice

          6 Stamens 4, 5, or 6; sepals 4 or 5; petals 4 or 5.

             7 Petals 4, distinct; stamens 6

             7 Petals 5, fused; stamens 2, 4, or 5.

               8 Corolla radially symmetrical; stamens 5

               8 Corolla 2-lipped, bilaterally symmetrical or asymmetrical; stamens 2 or 4.

                 9 Corolla lobes twisted so as to make the flower asymmetrical; stamens 4

      4 Leaf lobing palmate.

                   10 Petiole attachment peltate.

                     11 Leaves < 10 cm in diameter

                     11 Leaves > 15 cm in diameter

                   10 Petiole attachment marginal.

                       12 Ovary inferior.

                          13 Petals 4; stamens 8; fruit a capsule

                          13 Petals 5; stamens 5; fruit a schizocarp of 2 mericarps.

                            14 Fruit tuberculate; leaves 3-lobed

                            14 Fruit smooth; leaves with 5 or more lobes

                       12 Ovary superior, or half-inferior by fusion of a hypanthium a part of the way up the ovary wall.

                              15 Gynoecium of separate pistils (each with a single carpel); fruit an aggregate.

                                16 Perianth of 5 green sepals and 5 colored petals.

                                  17 Carpels partly fused, arrayed in a ring of 10-20

                                  17 Carpels separate, spiral, many

                                16 Perianth of a single whorl of 3-12 petaloid sepals (the petals absent or small and rudimentary).

                                    18 Leaves 2, the single flower terminal and associated with the upper leaf; fruit an aggregate of berries

                                    18 Leaves normally > 2, flowers not as above; fruit an aggregate of achenes, utricles, or follicles

                              15 Gynoecium of a single pistil (with 1-5 carpels); fruit simple.

                                       19 Hypanthium present, partially fused or not fused to the pistil; ovary partially inferior to superior

                                       19 Hypanthium absent; ovary superior.

                                         20 Petals connate at base; leaves sharply toothed

                                         20 Petals distinct; leaves with rounded lobes or teeth.

                                           21 Corolla radially symmetrical; petals 8-12; capsule fusiform, narrowed to both ends, > 5× as long as wide

                                           21 Corolla bilaterally symmetrical; petals 5; capsule ovoid, < 2× as long as wide

  2 Basal leaves not lobed, at most serrate or crenate (and sometimes also cordate, hastate, auriculate, or peltate at the base).

                                             22 Basal leaves petiolate, the blade with a cordate, hastate, auriculate, or peltate base.

                                               23 Leaf margins entire.

                                                 24 Inflorescence a terminal and/or axillary raceme, panicle, or cyme of many small flowers; fruit an achene; perianth uniseriate, of 0, 4-5, or 6 tepals.

                                                    25 Flowers unisexual; staminate flowers 4-5 tepals, pistillate flowers lacking a perianth

                                                    25 Flowers bisexual; flowers with 6 tepals

                                                 24 Inflorescence either a terminal spike, or a 1-7-flowered terminal cyme, or of a solitary axillary or terminal flower; fruit various; perianth biseriate (of differentiated sepals and petals (except uniseriate, of 3 fused sepals in ARISTOLOCHIACEAE).

                                                      26 Flowers bilaterally symmetrical; inflorescence a terminal spike (with > 20 flowers); petals 4, usually scarious, transparent; sepals 4, green; stamens 4

                                                      26 Flowers radially symmetrical; inflorescence either of a solitary flower or of a 1-7-flowered terminal cyme; petals 5, 8-12, or 0; sepals 5 (green), 3 (brown), or 5-9 (yellow); stamens 5, 12, or many.

                                                        27 Gynoecium of separate pistils (each with a single carpel); fruit an aggregate of achenes or follicles; flowers bright yellow, either of 5-9 distinct petaloid sepals, or of 8-12 distinct petals subtended by 3-4 green distinct sepals

                                                        27 Gynoecium either of a single pistil with 6 carpels or of a single pistil with 4 carpels or of 2 nearly separate carpels; fruit a simple capsule (or deeply 2-lobed); flowers white, brown, or greenish, either of 5 fused or distinct white petals and 5 fused or distinct green sepals, or of 3 fused brown or greenish petaloid sepals.

                                                          28 Flowers brown or green, of 3 fused brown or greenish petaloid sepals (and 0 petals); carpels 6; stamens 12; leaves 4-10 cm wide

                                                          28 Flowers white, of 5 white or whitish petals and 5 green sepals; carpels 2; stamens 5; leaves 1-12 (-15) cm wide

                                                            29 Petals separate; sepals separate; plant glabrous

                                                            29 Petals fused (at least basally in Dichondra); sepals fused; carpels 2; plant pubescent.

                                                              30 Fruit a deeply 2-lobed capsule; sepals longer or ca. as long as petals; petals not undulate, fused at their bases or distal ½, the anthers maroon or brown-colored; [common, widespread in our area]

                                                              30 Fruit a fleshy berry; sepals shorter than the petals; petals undulate, fused, the anthers yellow; [rare exotic]

                                               23 Leaf margins crenate, serrate, or incised.

                                                                 31 Gynoecium of separate pistils (each with a single carpel); fruit an aggregate; perianth of 5 green sepals and 5 colored petals (or of 2 or 4 (-5) white-colored tepals in Begonia).

                                                                   32 Flowers typically with 2 or 4 (-5) white-colored tepals; leaf bases conspicuously oblique (sometimes variegated); fruit unequally or subequally 3-winged capsules; [ornamental waifs or uncommon non-natives]

                                                                   32 Flowers with 5 green sepals and 5 colored petals (not merged into tepals); leaf bases oblique or not; fruit various but not 3-winged capsules; [natives and non-natives].

                                                                     33 Carpels 10-20, partly fused, arrayed in a ring; petals white, pink, red, or purplish

                                                                     33 Carpels many, separate, spiral; petals yellow or white.

                                                                       34 Flowers lacking a hypanthium; fruit an aggregate of achenes or aggregate of follicles

                                                                       34 Flowers with a hypanthium; fruit an aggregate of drupelets or aggregate of achenes

                                                                 31 Gynoecium of a single pistil (with 1-5 carpels); fruit simple.

                                                                         35 Flowers bilaterally symmetrical; inflorescence of a solitary flower; fruit a 3-locular capsule

                                                                         35 Flowers radially symmetrical; inflorescence an umbel (or composite of umbelliform units, or a terminal panicle.

                                                                           36 Ovary superior; inflorescence a terminal panicle or terminal raceme.

                                                                              37 Inflorescence a terminal raceme; perianth of 4 green sepals and 4 white petals; fruit a silique/silicle; fresh foliage in spring and summer with a strong garlic odor; larger leaves < 10 cm in diameter

                                                                              37 Inflorescence a terminal panicle; perianth of 6 cream-colored petaloid sepals; fruit a winged achene; fresh foliage lacking a garlic odor; larger leaves typically > 30 cm in diameter

                                                                           36 Ovary inferior; inflorescence an umbel (or a composite of umbellate units); fruit a schizocarp of mericarps.

                                                                                38 Petiole attachment peltate

                                                                                38 Petiole attachment marginal (the blade cleft to the petiole.

                                                                                  39 Leaf blades longer than wide, sharply V-cleft at the base and otherwise shallowly denticulate

                                                                                  39 Leaf blades as broad or broader than long, cleft at the base and also irregularly serrate or crenate around the margin

                                             22 Basal leaves petiolate or not, with a truncate, rounded, or cuneate leaf base.

                                                                                    40 Leaves tubular, with a sutured ventral flange, erect or reclining, adapted as a pitfall for insects (flat, phyllodial leaves sometimes present as well, common in the winter in some species, such as S. oreophila)

                                                                                    40 Leaves flat, not sutured into a tubular shape.

                                                                                      41 Stem leaves opposite; perianth 5-merous, at least the corolla bilaterally symmetrical (barely so in VALERIANACEAE), or the parts curved so as to be asymmetrical (Pedicularis in OROBANCHACEAE); stamens 2, 3, or 4.

                                                                                        42 Ovary inferior; stamens 3

                                                                                        42 Ovary superior; stamens 2 or 4.

                                                                                           43 Corolla narrowly tubular, the five lobes flaring at nearly 90 degrees and nearly radially symmetrical

                                                                                           43 Corolla distinctly 2-lipped (with prominently large upper and lower corolla lobes) or hooded (the upper lip hood-like), distinctly bilaterally symmetrical, or the lobes twisted so as to make the corolla asymmetrical.

                                                                                             44 Corolla yellow, the upper lip often slightly to strongly maroon, hooded but the corolla lobes twisted so as to make the flower asymmetrical

                                                                                             44 Corolla white, lavender, or blue, 2-lipped and bilaterally symmetrical.

                                                                                               45 Sepals separate to the base or nearly so, not forming a tube

                                                                                               45 Sepals connate for at least 0.3× their length to form a tube

                                                                                      41 Stem leaves alternate; perianth radially symmetrical (less commonly bilaterally symmetrical); stamens 5, 6-8, 9, 10 (rarely 4).

                                                                                                 46 Ovary inferior (or half-inferior in Samolus).

                                                                                                   47 Perianth 4-merous; stamens 8

                                                                                                   47 Perianth 5-merous; stamens 5.

                                                                                                     48 Inflorescence an umbel; fruit a schizocarp of 2 mericarps

                                                                                                     48 Inflorescence an axillary or terminal raceme; fruit a capsule

                                                                                                 46 Ovary superior.

                                                                                                        49 Pistils many, each with a single carpel; fruit an aggregate of achenes

                                                                                                        49 Pistil 1, with 1-5 carpels; fruit simple (a legume, silique/silicle, capsule, utricle, or schizocarp of 4 nutlets).

                                                                                                          50 Corolla bilaterally symmetrical (barely so in Limosella in SCROPHULARIACEAE); stamens 2, 4, 6, 8, or 10.

                                                                                                            51 Stamens 6-8 or 10.

                                                                                                              52 Petals separate; stamens 10

                                                                                                              52 Petals fused; stamens 10 or 6-8.

                                                                                                                53 Stamens 10, monadelphous

                                                                                                                53 Stamens 6-8, epipetalous

                                                                                                            51 Stamens 2 or 4.

                                                                                                                  54 Stamens 2

                                                                                                                  54 Stamens 4.

                                                                                                                     55 [plants of coastal wetlands]

                                                                                                                     55 [plants of uplands or inland seeps or fens]

                                                                                                                       56 Flowers (and subtending bracts) red or yellow

                                                                                                                       56 Flowers purple, blue, or lavender

                                                                                                          50 Corolla radially symmetrical; stamens 5, 10, 4-6, or 9.

                                                                                                                         57 Perianth of 6 tepals; stamens 4-6 or 9; carpels 3

                                                                                                                         57 Perianth of green sepals and more brightly colored petals; stamens 5 or 10; carpels 2, 3, 4, or 5.

                                                                                                                           58 Leaves covered with sticky, gland-tipped hairs (often red), as flypaper traps for insects

                                                                                                                           58 Leaves lacking sticky gland-tipped hairs.

                                                                                                                             59 Fruit a schizocarp of 4 nutlets (ovary obviously 4-lobed in flower)

                                                                                                                             59 Fruit a capsule or silique/silicle (or utricle in Limonium in PLUMBAGINACEAE).

                                                                                                                               60 Inflorescence of a solitary, terminal flower; carpels 2-3 (-4).

                                                                                                                                  61 Corolla with a long tube and flaring corolla lobes (united > ½ its length)

                                                                                                                                  61 Corolla of separate petals or united only for a short length (< ¼ its length).

                                                                                                                                    62 Leaves serrate

                                                                                                                                    62 Leaves entire

                                                                                                                               60 Inflorescence of several to many flowers; carpels 5 (3 in Galax in DIAPENSIACEAE).

                                                                                                                                      63 Inflorescence an umbel; petals recurved, pink to almost white

                                                                                                                                      63 Inflorescence a raceme or panicle.

                                                                                                                                        64 Fruit a silique/silicle; petals 4; stamens 6

                                                                                                                                        64 Fruit either a capsule or a utricle; petals 5; stamens 5 or 10.

                                                                                                                                          65 Inflorescence a somewhat to very diffuse panicle, with 3 or more orders of branching, not giving at all the impression that the overall inflorescence is made of racemose units.

                                                                                                                                            66 Leaves entire; stamens 5; [plants of tidal marshes]

                                                                                                                                            66 Leaves serrate or crenate; stamens 10; [plants of various habitats, especially rock outcrops and bottomland forests and streambanks, never in tidal marshes]

                                                                                                                                          65 Inflorescence either a single terminal raceme (sometimes spike-like), or of 1 to several terminal and axillary racemes (these sometimes combined into a diffuse panicle, but one whose structure is clearly made up of many racemes).

                                                                                                                                               67 Inflorescence of 1-several terminal and axillary racemes, the plant typically well-branched, especially from the base; stamens 5

                                                                                                                                               67 Inflorescence of a single, terminal raceme, the plant unbranched; stamens 10 (or 5, with 5 staminodes)

                                                                                                                                                 68 Inflorescence spike-like, the flowers many (> 40), barely pedicelled; capsule 3-locular

                                                                                                                                                 68 Inflorescence a raceme, the flowers fewer (< 20) and distinctly pedicelled; capsule 5-locular