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Support the Flora of the Southeastern US

2024 has been a banner year for making the best flora we can imagine. We've created:
With financial support from people like you, we are aiming even higher in 2025. Together we can accomplish all this: Vote on our 2025 priorities
  • Add Global Conservation Ranks (GRanks) vote
  • Professional graphic keys (polyclaves) to individual families/genera vote
  • 2 new FloraQuest apps: Florida & Mid-South vote
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  • iNaturalist integration in FloraQuest vote
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We've set a goal of recruiting 200 ongoing supporters to donate $15 or more each month in 2025. Please help us reach this goal and make next year's flora even better:

Click the number at the start of a key lead to highlight both that lead and its corresponding lead. Click again to show only the two highlighted leads. Click a third time to return to the full key with the selected leads still highlighted.

Key to Phlox

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1 Stems woody or suffrutescent, trailing or decumbent; leaves to 25 mm long (-60 mm long in P. bifida), to 3 (-5) mm wide, generally with short-shoots or fascicles of leaves in the axils of leaves of the sterile shoots.
  2 United portion of the style 5-12 mm long, the cleft portion ca. 1 mm long.
    3 Larger leaves > 3 cm long; nodes 4-5, spaced; petals deeply notched, the notch 1.5-5 mm deep
    3 Larger leaves < 2.5 cm long; nodes >6, crowded; petals shallowly notched, the notch 0.5-3 mm deep
  2 United portion of the style 1.5-4 mm long, the cleft portion 0.5-2 mm long.
      4 Leaves to 60 mm long and 5 mm wide; petal lobes about as wide as long; [ne. TX north through c. OK to sc. KS]
      4 Leaves to 30 cm long and 3 mm wide; petal lobes longer than broad; [s. VA south and west to e. MS; disjunct in se. TX]
        5 Pubescence with minute gland tips; corolla lobes cleft at the apex to 2.5 mm deep; [e. TX]
        5 Pubescence conspicuously gland-tipped; corolla lobes merely slightly emarginate at the apex; [AL east and north to s. VA].
          6 Fertile shoots (10-) 15-30 cm tall; upper leaves oblong-lanceolate, up to 12-25 mm long, 1.5-3 mm wide on sterile shoots, 2.5-5 mm wide on fertile shoots; pubescence of the inflorescence mostly with conspicuously glandular tips
          6 Fertile shoots (3-) 8-12 (-15) cm tall; upper leaves linear-lanceolate, up to 8-12 mm long, 0.5-1.5 mm wide on sterile shoots, 1.5-3 mm wide on fertile shoots; pubescence of the inflorescence mostly with finely glandular tips
1 Stems herbaceous, erect or decumbent; leaves (at least the larger) > 25 mm long and/or > 5 mm wide, generally lacking axillary fascicles of leaves.
             7 Style long, (12-) 14-26 mm long, the united portion 3-30× as long as the cleft portion; stamens equaling or exceeding the corolla tube (thus in part exserted).
               8 Plants forming colonies by rhizomes, stolons, and/or prostrate sterile shoots with evergreen to semi-evergreen leaves; flowering shoots 1-4 (-5) dm tall.
                 9 Plants with rhizomes and stolons tipped with clustered, evergreen, linear to lanceolate leaves 3-12 cm long, 5-10 (-12) mm wide
                 9 Plants with prostrate sterile shoots with scattered, semi-evergreen, spatulate to obovate leaves 1.5-4.5 cm long, 5-16 mm wide
               8 Plants not colony-forming by rhizomes or stolons; flowering shoots (3-) 5-20 dm tall.
                   10 Leaf margin ciliate-serrulate; lateral veins of the leaves readily apparent, these joining to form a connecting vein parallel to the leaf margin.
                     11 Bracts of the inflorescence pubescent with glandular hairs; corolla tube glabrous; leaves opposite; nodes usually 8-15; leaves usually 2-3× as long as wide
                     11 Bracts of the inflorescence pubescent with non-glandular hairs; corolla tube pubescent (rarely glabrous); leaves subopposite (at least near the inflorescence); nodes usually 15-40; leaves usually 3-4× as long as wide
                   10 Leaf margin smooth or slightly rough; lateral veins of the leaves not readily apparent, not forming a connecting vein parallel to the leaf margin.
                       12 Flowering shoots arising from decumbent stems; nodes below the inflorescence 3-7
                          13 Sterile, decumbent stems elongate; nodes (5-) 6 (-7); lower leaves short-petioled
                       12 Flowering shoots arising from rhizomes; nodes below the inflorescence 7 or more.
                            14 Cymes several, the lower on rather short and uniform peduncles, thus the inflorescence as a whole subcylindric in outline.
                              15 Nodes 7-15, well-spaced; upper leaves oblong to ovate, cordate at the base; flowering early summer
                            14 Cymes solitary or several, if several then the lower on long peduncles, thus the inflorescence as a whole broadly rounded or even flat-topped.
                                16 Calyx subcylindric, the sepals fairly broad, with a rather weak midrib, the junction-membranes thin, narrow, becoming markedly plicate-keeled
                                16 Calyx subcampanulate, the sepals narrow with a well-developed midrib, the junction-membranes firm, broad and flat (to slightly plicate-keeled)
             7 Style short, 1-4 mm long, the united portion 1-1.5 (-2)× as long as the cleft portion; stamens shorter than the corolla tube (thus included).
                                  17 Upper leaves alternate; annual; corollas red, white, bright purple, purplish-pink, or variegated.
                                    18 Corolla tube constricted at orifice; corollas bright purple (rarely pink or nearly white), with a conspicuous yellow eye; [TX]
                                    18 Corolla tube not constricted at the orifice; corollas red, white, purplish-pink, or variegated; [collectively widespread].
                                       19 Largest leaves > 10× as long as wide; corolla tubes 10-14 mm long, glabrous or pilose; corollas purplish-pink, with well-developed white 'eye'; [s. and se. TX].
                                       19 Largest leaves < 10× as long as wide; corolla tubes (10-) 14-20 mm long, usually pubescent (very rarely glabrous); corollas red, white, pink, lavender, or variegated; [collectively widespread].
                                           21 Populations variable in flower color, usually mixes of white, pink, lavender, red, and mixtures; [collectively widespread, naturalized in dry sandy soils of roadsides, fields, and disturbed areas]
                                           21 Populations uniform in flower color; [sc. OK south to s. TX].
                                             22 Corollas bright red or crimson to deep lavender; mid-stem leaves mostly sessile or abruptly tapered to the blade base; [se. TX]
                                             22 Corollas pink or lavender; mid-stem leaves mostly gradually tapered at base; [c., nc., and sc. TX].
                                  17 Upper leaves opposite or subopposite; perennial; corollas blue, lavender, or pink; [native, mostly of forests, woodlands, or roadbanks].
                                                 24 Sterile shoots rooting at the nodes; leaves broad-elliptic, ca. 2-3× as long as wide; sepals acuminate to very slightly awned, the awn 0-0.5 mm long; corolla tube glabrous.
                                                 24 Sterile shoots not rooting at the nodes; leaves narrowly ovate, lanceolate, or linear, ca. 4-10× as long as wide; sepals awned, the awn 0.5-3.0 mm long; corolla glabrous, pilose, or glandular-pubescent.
                                                      26 Cymes compact, the lowest branches short, < 0.5 cm long; corolla glabrous; pedicels 1-6 mm long.
                                                        27 Leaves and bracts oblong-elliptic to lanceolate, acute to obtuse (rarely acuminate), the larger 20-40 (-50) mm long, 4-8 (-12) mm wide, ca. 5× as long as wide; bracts below the inflorescence hiding the calyces
                                                        27 Leaves and bracts linear to lanceolate, acuminate, the larger 35-45 mm long, 3-5 mm wide, ca. 10× as long as wide; bracts below the inflorescence not hiding the calyces
                                                      26 Cymes open, the lowest branches elongate, > 1 cm long; corolla usually glandular-pubescent or pilose (rarely glabrous); pedicels 1-8 (-12) mm long
                                                                   32 Upper stem leaves mostly linear, the base rounded or truncate; stems with non-glandular hairs towards the base, grading to glandular hairs towards the tip of the stem