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

illscented wakerobin, southern nodding trillium

Rhizomes

horizontal, brownish, thick, praemorse, fleshy.

short, thick, tapered to point distally.

Scapes

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

1–3, round in cross section, 1.5–4 dm, robust, glabrous.

Bracts

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).

sessile to subsessile;

blade bright green, veins not engraved, rhombic, broader than long, 6–15 × 6–16 cm, not glossy, base attenuate, apex acuminate.

Flower

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.

strongly recurved below bracts;

sepals shorter than petals and somewhat obscured by them, spreading, green, very rarely streaked with red, lanceolate-elliptic, 15–40 × 7–17 mm, margins entire, apex acuminate;

petals recurving in distal 1/2 in most forms (forms from Alabama with petals slightly narrower and strongly recurved just above base), white, rarely 2-colored with base rose or dark purple and white, adaxial veins conspicuous, broadly ovate-elliptic, 2.5–5 × 0.8–3.5 cm, heavy-textured, margins entire, without undulations, apex abruptly acuminate;

stamens ± straight, 8–18 mm;

filaments deep purple, 2–8 mm, slender;

anthers ± straight, dark purple, 12–16 mm, thin, dehiscence introrse;

connectives not extended beyond anther sacs;

ovary prominent, purple-streaked or maroon distally or throughout, flask-shaped, 6-angled, 14–17 mm, widely attached at base;

stigmas recurved, distinct, dark purple, not lobed adaxially, subulate, 2–5 mm, fleshy;

pedicel strongly recurved beneath bracts, 1–7+ cm.

Fruits

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

baccate, dark reddish purple, fragrance faintly of fruit, ovoid to orbicular, 1.7 × 2 cm, fleshy, juicy.

2n

= 10.

= 10.

Trillium sessile

Trillium rugelii

Phenology Flowering spring (Mar–early May). Flowering mid spring (mid Apr–May).
Habitat 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 Deciduous forest hillsides and coves, inner piedmont, mostly in alluvial soils along stream banks and flats
Elevation 100–300 m (300–1000 ft) 200–700 m (700–2300 ft)
Distribution
from FNA
AL; AR; IL; IN; KS; KY; MD; MI; MO; NC; NY; OH; OK; PA; TN; VA; WV
[WildflowerSearch map]
[BONAP county map]
from FNA
AL; GA; NC; SC; TN
[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.)

The Alabama plants of Trillium rugelii differ from those in the Great Smoky Mountains region in having usually smaller bracts, narrower ovate petals strongly recurved from the base, and strongly fragrant flowers with the odor of old-fashioned garden roses. The anther color and structure are the same as in the mountain form. Hybrids between T. vaseyi and T. rugelii occur frequently.

Trillium rugelii has been much confused with T. cernuum in past floras, and it is the taxon upon which most reports of T. cernuum south of Virginia are based.

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

Source FNA vol. 26, p. 115. FNA vol. 26, p. 103.
Parent taxa Liliaceae > Trillium > subg. Phyllantherum Liliaceae > Trillium > subg. Trillium
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. simile, T. stamineum, 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. sessile, T. simile, T. stamineum, T. sulcatum, T. underwoodii, T. undulatum, T. vaseyi, T. viride, T. viridescens
Name authority Linnaeus: Sp. Pl. 1: 340. (1753) Rendle: J. Bot. 39: 331, plate 426, fig. B1901 (as rugeli)
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