Flora of the Southeastern United States

1 Basal leaves lobed but not fully divided into 3 or more leaflets; stem leaves either unlobed and borne immediately below the flower (easily mistakable as a calyx) or lobed and borne well below the flower.

  2 Basal leaves lobed, and also toothed and variously cleft; stem leaves lobed and borne well below the flower; leaves not variegated

1 Basal leaves compound, fully divided into 3 or more leaflets; stem leaves lobed and borne well below the flower.

    3 Stem branched, 4-11 dm tall, bearing 2 or more flowers; stem leaves petiolate; [subsection Virginianae].

      4 Heads of fruits cylindrical, >2× as long as diameter; fruit beaks 0.3-1.0 mm long; stem leaves (3-) 5-9 per whorl; peduncle naked above the stem leaves

      4 Heads of fruits ovoid to short-cylindric, <2× as long as diameter; fruit beaks 1.0-1.5 mm long; stem leaves 2-3 (-5) per whorl; peduncle with 2 additional subtending leaves.

        5 Base of stem leaves usually truncate to subtruncate, sometimes reniform or cordate, terminal leaflets deep green, margins proximally concave- to straight-sided, distally incised, thinly pubescent; anthers typically < 0.8-1.2 (-1.5) mm long; heads of achenes more or less ovoid-cylindric, 8-10 (-11) mm in diameter

        5 Base of stem leaves cordate or reniform, rarely subtruncate, terminal leaflets light green, margins proximally mostly straight- to convex-sided, variously lobed or serrate, variously pubescent; anthers typically > (0.9-) 1.1-1.5 (-1.7) mm long; heads of achenes ovoid to ovoid-cylindric, (9-) 10-12 (-14) mm in diameter

    3 Stem unbranched, 0.5-4 dm tall, bearing 1 flower; stem leaves sessile or petiolate.

          6 Sepals (5-) 8-20, cream-white, violet, blue, pink, or green; stem leaves sessile; [subsection Anemone; series Carolinianae].

             7 Stem densely pubescent above and below the stem leaves; stem leaves borne above the midpoint of the stem at anthesis; plant from a globose, vertically oriented bulb, lacking rhizomes; basal leaves 1-ternate, the 3 lobes sublobed or toothed, but not additionally divided; involucral leaves (1.5-) 3-6 cm long; achene bodies 2.7-3.5 mm long; achene beak sinuous, hidden in the achene indument

             7 Stem densely pubescent above the stem leaves, glabrous to very sparsely pubescent beneath the stem leaves; stem leaves borne at or below the midpoint of the stem at anthesis; plant with slender, horizontal rhizomes; basal leaves 1-3-ternate, the 3 primary lobes usually further divided into linear segments; involucral leaves 1-2.5 (-3) cm long; achene bodies 1.5-2.5 (-3.0) mm long; achene beak straight, extending out of the achene indument

          6 Sepals 5 (-8), white or bright yellow; stem leaves petiolate, the leaflets ovate, obovate, elliptic, lanceolate, or oblanceolate 2-8 cm long, 8-30 mm wide; [subsection Anemonanthea].

               8 Sepals bright yellow; [exotic]

               8 Sepals white; [natives, collectively widespread]

                 9 Ovaries and achenes with hairs 0.1-0.2 mm long; terminal leaflet broadest at or below the middle (lanceolate or ovate), serrate to below the middle; sepals 15 mm or more long

                 9 Ovaries and achenes with hairs 0.5-1.0 mm long; terminal leaflet broadest at or above the middle (elliptic, oblanceolate, or obovate), serrate only above the middle; sepals < 15 mm long.

                   10 Achene bodies 2.5-3.0 mm long; lateral leaflets of basal leaves toothed only (rarely lobed); terminal leaflet usually broadest at the middle; styles 0.5-1 mm long; sepals about 8 mm long

                   10 Achene bodies 3.0-4.5 mm long; lateral leaflets of basal leaves lobed or cleft (sometimes only toothed); terminal leaflet usually broadest above the middle; styles 1-2 mm long; sepals 6-15 mm long

1 Flowers bilaterally symmetrical, the upper sepal hooded or spurred; [tribe Delphinieae].

  2 Upper sepal hooded or helmet-shaped; petals hidden by the sepals; perianth blue or creamy white; stems weak, clambering, reclining, vining, or ascending in a curve

  2 Upper sepal spurred; petals at least partly exserted from the sepals; perianth blue, pink, white, or greenish; stems strong, erect, normally straight

1 Flowers radially symmetrical, no perianth parts spurred or hooded (except the 5 sepals spurred in Myosurus).

    3 Petals present, white or yellow, larger and more conspicuous than the sepals; sepals present, green; [in other words, with a second, green, less conspicuous perianth whorl below the largest and colored perianth whorl; note that some Anemone have a calyx-like involucre of 3 bracts subtending each flower]; [tribe Ranunculeae].

      4 Basal leaves linear to linear-spatulate, mostly 4-8 cm long, 1-3 mm wide; receptacle elongate, 1-6 cm long (superficially resembling a Plantago inflorescence)

      4 Basal leaves various, but not as above; receptacle globose to sub-cylindric, mostly < 1 cm long

        5 Sepals 3 (-4); petals 7-12; achenes pubescent, beakless; leaves simple, cordate, unlobed; [introduced garden plants]

        5 Sepals (3-) 5 (-6); petals typically 5-9 (10 in some "doubled" forms); achenes smooth or variously ornamented with spines, papillae, or tubercles, sometimes also pubescent; leaves various, usually not at once simple, cordate, and unlobed (except in Halerpestes); [native or introduced].

          6 Cauline leaves absent; basal leaves cordate, unlobed

          6 Cauline leaves present, well-developed; basal leaves not simultaneously cordate and unlobed

    3 Petals absent (or modified into relatively inconspicuous nectaries or staminodia); sepals present and petaloid (white, yellow, yellow-green, cream, or blue).

             7 Petaloid sepals 3-5 mm long, caducous; stamens white and showy; [tribe Ranunculeae]

             7 Petaloid sepals 6-40 mm long, not caducous; stamens not notably white and showy.

               8 Leaves opposite, distributed along the stem; style plumose; [tribe Anemoneae]

               8 Leaves all basal, or with a few alternate or whorled involucrate leaves on the stem; style not plumose.

                 9 Petaloid sepals white, bluish, or blue; basal leaves 3-5 (-7)-lobed; [tribe Anemoneae]

                   10 Leaves lobed, and also toothed and variously cleft; leaves not variegated

                 9 Petaloid sepals yellow, green, or whitish (sometimes marked with purple); basal leaves unlobed, or palmately cleft into 5-11 (-many) segments.

                     11 Leaves cordate-reniform, unlobed; sepals bright yellow; petals absent; [native, of bogs and marshes]; [tribe Caltheae]

                     11 Leaves palmately or pedately lobed or divided; sepals green, greenish, dull yellow, or whitish; petals modified into tubular nectaries; [introduced, rarely persistent or escaped from cultivation].

                       12 Sepals 5, green or maroon, persistent in fruit; cauline leaves present; leaf margins sharply and finely serrate; [tribe Helleboreae]

                       12 Sepals 5-8, yellow; cauline leaves either present, alternate, or absent, except for the involucre of 3 bracts which immediately subtends the flower.

                          13 Cauline leaves absent, except the 3 involucral bracts immediately subtending the flower; [tribe Cimicifugeae]

                          13 Cauline leaves present, alternate, the uppermost > 1 cm below the flower; [tribe Helleboreae]

1 Fruit a follicle, each carpel with 2 or more ovules.

  2 Leaves cordate-reniform, toothed, not lobed or divided; [tribe Caltheae]

  2 Leaves variously palmately or pedately lobed or divided.

    3 Carpels 1-3; plants 3-30 dm tall; [native, except Consolida]; [tribe Delphinieae].

      4 Stems weak, clambering, reclining, or vining

      4 Stems strong, erect

    3 Carpels 3-6; plants 1-5 dm tall; [introduced, rarely persistent or escaping].

        5 Cauline leaves absent, except for the involucre which immediately subtends the fruit; [tribe Cimicifugeae]

        5 Cauline leaves present; [tribe Helleboreae].

1 Fruit an achene (or dehiscent utricle in Trautvetteria), each carpel with 1 ovule.

          6 Leaves opposite, distributed along the stem; style plumose; [tribe Anemoneae]

          6 Leaves all basal, or with a few alternate or whorled involucrate leaves on the stem; style not plumose.

             7 Basal leaves linear to linear-spatulate, mostly 4-8 cm long, 1-3 mm wide; receptacle elongate, 1-6 cm long (superficially resembling a Plantago inflorescence); [tribe Ranunculeae]

             7 Basal leaves various, but not as above, generally long-petiolate, with an expanded, crenate-toothed, 3-lobed, or palmately-lobed blade; receptacle globose to sub-cylindric, mostly < 1 cm long.

               8 Fruit a dehiscent utricle; cauline leaves alternate; [tribe Ranunculeae]

               8 Fruit an achene; cauline leaves opposite or whorled (or alternate in Ranunculus, or reduced to alternate scale-like bracts in Halerpestes).

                 9 Cauline leaves opposite or whorled, or reduced to 3 sepal-like involucral bracts immediately subtending the flower; sepals absent (but in “Hepatica” mimicked by the bracts); [tribe Anemoneae]

                   10 Leaves lobed, and also toothed and variously cleft; leaves not variegated

                 9 Cauline leaves alternate; sepals present; [tribe Ranunculeae]

                     11 Achenes smooth or variously ornamented with spines, papillae, or tubercles, sometimes also pubescent, usually noticeably beaked, the beak > 0.3 mm long; leaves various, usually not at once simple, cordate, and unlobed ; [native or introduced]

                     11 Achenes not ornamented with spines, papillae, or tubercles, pubescent or glabrous, beakless; leaves simple, unlobed.

                       12 Sepals 3; [introduced garden plants]

                       12 Sepals 5; [native, of s. NJ northwards]