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Blue Ridge wakerobin, twisted trillium

sessile trillium, sessile-flower wake-robin, toad trillium, toadshade

Rhizomes

horizontal, brownish, short, thick, praemorse, not brittle.

horizontal, brownish, thick, praemorse, fleshy.

Scapes

1–3, round in cross section, 1.5–3 dm, slender to stout, pilose-pubescent, rarely glabrous.

1–3, round in cross section, 0.8–2.5 dm, slender to stout, glabrous.

Bracts

held well above ground, sessile;

blade light silvery or bluish green with strong to faint mottling in darker colors, mottling becoming obscure with age, ovate-lanceolate to broadly ovate, 6.3–7.6 × 3.3–5 cm, larger bracts abaxially pilose-pubescent, margins entire, apex acute.

held well above ground, sessile;

blade green to bluish green, strongly to sparsely mottled, mottling becoming obscure with age, oval to suborbicular, 4–10 × 2–8 cm, base broadly attached, apex rounded-acuminate to bluntly parallel sided-acuminate (rounded basally to its broad attachment).

Flower

erect, odor strong, of carrion;

sepals displayed above bracts, spreading to ± horizontal position, green, purple markings adaxially, lanceolate-elliptic, 17–40 mm, margins entire, purple, apex acuminate;

petals long-lasting, spreading and carried in ± horizontal position unlike any other sessile trillium, very deep maroon to blackish red, rarely yellow, purple-streaked, with 1–2 spiral twists, narrowly elliptic to lanceolate or linear, narrow, 1.5–3.8 × 0.3–0.6 cm, rarely broader, thick-textured, margins entire, apex sharply acute to rounded, tips incurving slightly;

stamens fully exposed, somewhat stiffly erect, dark purple, 16–24 mm, thick;

filaments dark purple, 2–4 mm, basally dilated;

anthers erect, straight, dark purple, 13–18 mm, thick, dehiscence extrorse;

connectives dark purple, straight, coarse, flat, ± not extended beyond anther sacs;

ovary dark purple, oval, 6-angled, 5–7 mm;

stigmas erect, widely spreading, often strongly recurved or recoiled, distinct, purple, linear, 4–10 mm, slightly thickened basally.

erect, odor pungent, spicy;

sepals displayed above bracts, spreading, green, variously streaked with maroon, lanceolate-oblanceolate, 9–35 × 4–8 mm, margins entire, apex rounded-acuminate;

petals long-lasting, erect, ± connivent, ± concealing stamens and ovary, maroon, brownish maroon, green, or yellowish green, not spirally twisted, oblanceolate to elliptic, occasionally almost orbicular, 1.7–3.5 × 0.7–2 cm, thick-textured, narrowed near basal attachment (but not truly clawed), margins entire, apex gradually rounded-tapered to acute;

stamens straight, 10–23 mm;

filaments red-purple, 2–5 mm, dilated basally;

anthers erect, straight, gray-purple, 9–16 mm, thick, dehiscence introrse;

connectives purplish brown, straight, projecting 2–5+ mm beyond anther sacs;

ovary greenish white basally, purple distally, ovoid to globose, 6-angled, pyramidally narrowed to stigmas, 4–8.5 mm;

stigmas erect, divergent-recurved, distinct, purple, subulate, 1–5 mm, ± fleshy.

Fruits

baccate, purple, odorless, ovoid, strongly 6-angled, sometimes winged, 2 × 1–1.5 cm, pulpy, moist.

baccate, dark greenish purple, odorless, subglobose, 6-angled, angles somewhat winglike, pulpy, not juicy.

2n

= 10.

= 10.

Trillium stamineum

Trillium sessile

Phenology Flowering spring (late Mar–mid May). Flowering spring (Mar–early May).
Habitat Dry, upland woods of deciduous trees, deciduous forest mixed with pines, soil on limestone outcroppings, mesic woods, sandy flats along medium streams, steep wooded slopes, banks of rivers Rich woodlands, limestone districts, calcareous soils, floodplains, riverbanks, clayey alluvium, less fertile soils, high, dry limestone woods, persists under light pasturing, in fencerows and brushy areas after lumbering
Elevation 50–200 m (200–700 ft) 100–300 m (300–1000 ft)
Distribution
from FNA
AL; MS; TN
[WildflowerSearch map]
[BONAP county map]
from FNA
AL; AR; IL; IN; KS; KY; MD; MI; MO; NC; NY; OH; OK; PA; TN; VA; WV
[WildflowerSearch map]
[BONAP county map]
Discussion

Trillium sessile is rather uniform throughout its range, with few color forms.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Source FNA vol. 26, p. 115. FNA vol. 26, p. 115.
Parent taxa Liliaceae > Trillium > subg. Phyllantherum Liliaceae > Trillium > subg. Phyllantherum
Sibling taxa
T. albidum, T. angustipetalum, T. catesbaei, T. cernuum, T. chloropetalum, T. cuneatum, T. decipiens, T. decumbens, T. discolor, T. erectum, T. flexipes, T. foetidissimum, T. gracile, T. grandiflorum, T. kurabayashii, T. lancifolium, T. ludovicianum, T. luteum, T. maculatum, T. nivale, T. ovatum, T. parviflorum, T. persistens, T. petiolatum, T. pusillum, T. recurvatum, T. reliquum, T. rivale, T. rugelii, T. sessile, T. simile, T. sulcatum, T. underwoodii, T. undulatum, T. vaseyi, T. viride, T. viridescens
T. albidum, T. angustipetalum, T. catesbaei, T. cernuum, T. chloropetalum, T. cuneatum, T. decipiens, T. decumbens, T. discolor, T. erectum, T. flexipes, T. foetidissimum, T. gracile, T. grandiflorum, T. kurabayashii, T. lancifolium, T. ludovicianum, T. luteum, T. maculatum, T. nivale, T. ovatum, T. parviflorum, T. persistens, T. petiolatum, T. pusillum, T. recurvatum, T. reliquum, T. rivale, T. rugelii, T. simile, T. stamineum, T. sulcatum, T. underwoodii, T. undulatum, T. vaseyi, T. viride, T. viridescens
Name authority Harbison: Biltmore Bot. Stud. 1: 23. (1901) Linnaeus: Sp. Pl. 1: 340. (1753)
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