1 Leaves simple; plant a tree or shrub.

  2 Leaves either cordate and < 2× as long as wide, or linear and > 10× as long as wide; leaves opposite, alternate, or 3-whorled (or a mixture of those arrangements); [collectively widespread in our area]; fruit a capsule (dehiscent), narrowly cylindrical, (9-) 14-30 (-36) cm long, < 1.5 cm in diameter; [tribe Catalpeae].

    3 Leaf blades heart-shaped and broadly ovoid to orbicular (< 2× as long as wide), with a cordate base; stamens 2; medium to large tree; [widespread in our region]

    3 Leaves linear (> 10× as long as wide, with a narrowly cuneate base; stamens 4; shrub to small tree; [TX westwards and southwestwards]

  2 Leaves spatulate to obovate, 2-6× as long as wide; leaves alternate (though sometimes closely fascicled on short (spur) shoots, with the arrangement difficult to discern); fruit a berry (indehiscent), spherical, elliptical, or obovoid, 5-35 cm long, 4-35 cm in diameter; [s. peninsular FL only in our region]; [tribe Crescentieae].

      4 Leaves obovate, mostly widest ½ to ¾ of the way from blade base to apex; leaves alternate and spaced along main branches; berry 5-12 cm long, elliptical or obovoid, the apex extended as a blunt point

      4 Leaves spatulate, mostly widest at a point > ¾ of the way from blade base to apex; leaves alternate but closely fascicled on short (spur) shoots, with the arrangement difficult to discern; berry 15-35 long, spherical, the apex smoothly rounded

1 Leaves compound; plant a liana, tree, or shrub.

        5 Leaves either all 2-foliolate, with a tendril in the terminal position (this often withered and absent on older leaves), or a mixture of 2-foliolate and 3-foliolate, with at least some leaves on a branch 2-foliolate; plant a liana; [tribe Bignonieae].

          6 Leaflets <1.5× as long as wide, the venation subpalmate (usually with 5 veins palmate or nearly so at the blade base); leaf bases cordate to subcordate; leaf apices abruptly acuminate; corollas white or cream, with a yellow throat; fruit ellipsoid, 1.5-2.5× as long as wide, the surface strongly echinate; tendrils terminating in expanded adhesive disks

          6 Leaflets 1.3-5× as long as wide, the venation pinnate; leaf bases cordate, subcordate, auriculate, truncate, rounded, or cuneate; leaf apices abruptly to gradually acuminate; corollas red, orange, bright yellow, or pink; fruit linear or ellipsoid, > 6× as long as wide, the surface smooth; tendrils narrowing to pointed tips.

             7 Tendrils hooked, claw-like, the 3 equal branches each with a stiff, sharply-pointed hook-like tip; corollas bright yellow on inside and outside

             7 Tendrils not hooked, not claw-like, the 3 or more branches usually unequal and flexuous when fresh (though sometimes curved at the tip).

               8 Corollas pink, the tube white or paler pink; tendrils simple; fresh foliage with garlic odor when bruised; [exotic, FL peninsula]

               8 Corollas red to orange-red, sometimes with yellow as well; tendrils with 3 or more branches; fresh foliage not garlic-scented; [collectively widespread].

                 9 Corollas red to red-orange, the corolla lobes often with a yellow inner surface; lower 3 corolla lobes each 1-1.5× as long as wide, the lateral 2 descending; pseudostipules leaflike, at petiole base, ovate or orbicular; corolla tube 1.5-3× as long as the diameter; [widespread native in our region, south to c. peninsular FL, and also cultivated]

                 9 Corollas uniformly red to red-orange; lower 3 corolla lobes 2-4× as long as wide, the lateral 2 born at 90 degrees to the lower and therefore at 180 degrees to one another; pseudostipules absent or minute; corolla tube 5-9× as long as the diameter; [exotic, FL peninsula]

        5 Leaves 3-many-foliolate; plant a tree, shrub, or liana.

                   10 Leaves palmately compound, with (3-) 5 (-7) leaflets; [exotic, FL peninsula]; [tribe Crescentieae].

                     11 Leaves, young branches and inflorescence with indumentum of simple, branched or stellate hairs; corollas yellow

                     11 Leaves, young branches and inflorescence with indumentum of stalked or sessile lepidote scales; corollas yellow or pink

                   10 Leaves pinnately or bipinnately compound, with (5-) 7-many leaflets; [collectively widespread in our region].

                       12 Leaves bipinnately compound; trees; [FL peninsula].

                          13 Leaflets 0.3-1.2 cm long; corollas lavender-blue; [tribe Jacarandeae]

                          13 Leaflets 4-7 cm long; corollas white to pale yellow; [tribe Tecomeae]

                       12 Leaves pinnately compound; shrubs, lianas, or trees; collectively widespread in our region].

                            14 Leaflet margins entire; plant a tree; corolla campanulate; calyx splitting along the lower side, appearing spathe-like; [s. FL only]; [tribe Coleae]

                            14 Leaflet margins serrate; plant a liana, shrub, or small tree; corolla tubular or funnel-like; calyx not splitting; [collectively widespread in our area, including FL peninsula]; [tribe Tecomeae].

                              15 Plant a liana; [collectively widespread in our region].

                                16 Corollas pink, with purplish lines in the throat; calyx white to pink; plants not climbing by adventitious roots; [exotic, FL peninsula]

                              15 Plant a shrub or small tree; [FL peninsula only; exotic].

                                  17 Corolla yellow; corolla tube straight; leaflet margins finely serrate; leaflet apex acute

                                  17 Corolla orange; corolla tube narrow, strongly curved-arching; leaflet margins coarsely serrate; leaflet apex rounded to sub-acute

1 Leaves 2-3-foliolate.

  2 Leaves 2-foliolate, with a branched tendril in the terminal position (this sometimes not developed, or withered); liana

  2 Leaves 3-foliolate, lacking tendrils; shrub, liana, or tree.

    3 Upright shrub or tree.

      4 Leaflets entire, glandular-dotted; [n. FL southwards

      4 Leaflets serrate or serrulate, not glandular-dotted; [collectively widespread].

        5 Leaflets 3-5 (-7), coarsely and jaggedly serrate, with < 5 teeth per leaflet side; fruit a schizocarp of 2 samaroid mericarps (maple “keys”)

        5 Leaflets 3, evenly serrulate, with > 10 teeth per leaflet side; fruit an inflated capsule

    3 Liana or sprawling shrub.

          6 Flowers yellow with fused petals; stems stiff, green

          6 Flowers either white, radially symmetrical, with separate petaloid sepals (Clematis), or blue, bilaterally symmetrical, with fused petals (Vitex).

             7 Leaves 3-more-foliolate; flowers white, radially symmetrical, uniseriate, with white petaloid sepals and no petals

             7 Leaves 1 (-3) foliolate; flowers blue, bilaterally symmetrical, biseriate, with green calyx and blue corolla

1 Leaves 4-15-foliolate.

               8 Leaves palmately compound.

                 9 Leaflets serrate; flowers white, yellow, or red; fruit a leathery capsule, irregularly spheroidal, 2-9 cm in diameter, with 1-3 (-6) large seeds, each with a large pale hilum contrasting with the dark brown color of the rest of the seed

                 9 Leaflets entire; flowers blue, pink, or purple; fruit either a 4-seeded drupe, < 0.5 cm in diameter, or an elongated capsule, 8-10 cm long and ca. 0.7 cm in diameter.

                   10 Leaflets < 3× as long as wide, broadly rounded at the tip; fruit an elongated capsule, 8-10 cm long and ca. 0.7 cm in diameter [peninsular FL]

                   10 Leaflets > 4× as long as wide, acute at the tip; fruit a 4-seeded drupe, < 0.5 cm in diameter; [widespread in our region]

               8 Leaves pinnately compound, bipinnately compound, or more complexly compound.

                     11 Plant a liana (woody vine).

                       12 Leaves either pinnately compound, the leaflets 3-7 and coarsely serrate, or more complexly compound, the leaflets 5-many, not serrate though often lobed; perianth uniseriate, with a white, pink, or purplish aposepalous calyx and no corolla; fruit an aggregate of plumose achenes; stems to 1 cm in diameter, brown or green

                     11 Plant a tree or shrub, with stiff branches.

                          13 Leaves 3-7-foliolate and strictly 1-pinnate; leaflets with a few very coarse teeth; 1st year stems green; fruit a pair of winged, asymmetrical samaroid mericarps

                          13 Leaves 3-15-foliolate, 1-pinnate or partially 2-pinnate; leaflets evenly serrate with many teeth or entire; 1st year stems tan to brown (very new growth may be green); fruit either a symmetrical (winged) samara (Fraxinus) or a purplish-black, many-seeded berry (Sambucus).

                            14 Fruit a purplish-black or red, 4-seeded berry (Sambucus); plant a shrub or small tree; stems hollow or pithy; petiole prominently grooved on the upper side; fresh leaves somewhat fleshy in texture

                            14 Fruit either a green or tan, symmetrical (winged) samara or a blackish 5-seeded dryish drupe; plant a small to large tree; stems solid and woody; petiole nearly round in ×-section (not grooved); fresh leaves membranaceous or coriaceous in texture.

                              15 Fruit a symmetrical samara; axillary buds suprapetiolar (though sometimes almost hidden within the strongly U-shaped petiolar attachment; [common native (also planted)]

                              15 Fruit a nearly spherical 5-seeded dry drupe; axillary buds infrapetiolar (hidden by the swollen petiole base; [rarely escaped exotic]