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

bashful trillium, bashful wakerobin, Catesby's trillium

Rhizomes

horizontal, brownish, thick, praemorse, fleshy.

short, tapered to a point distally.

Scapes

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

1–2, round in cross section, 2–4.5 dm, slender, 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).

usually raised somewhat, exposing flower;

blade green, often with underlying purplish maroon in well-lighted plants, major veins on adaxial surface deeply engraved, elliptic-ovate, 6.5–15 × 4–8 cm, including elongated, petiolelike base, proximal 1/3 of leaf gradually tapered to base, margins often slightly raised, apex blunt-acute to 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.

opening at or recurved below bracts, rarely erect;

sepals falcate-recurved, green or streaked with purple, linear-lanceolate, 20–45 × 7–8 mm, margins ± flat, apex acuminate;

petals falcate-recurved distally, white, pink, or rose, darkening to pink or nonfading with age, veins visible but not appearing engraved, elliptic-oblong to oblong-lanceolate, 3.5–5 × 1–2+ cm, thin-textured, bases somewhat imbricated, forming funnel-like tube, margins undulate, apex acuminate;

stamens prominent, recurved, 16–25 mm;

filaments white, slightly longer and narrower than anthers;

anthers recurving, bright yellow, 5–14 mm, thick, dehiscence introrse;

ovary inconspicuous, white, angular-ovoid, deeply 6-angled, 4–12 × 3–7 mm, slender, base narrow;

style 2–6 mm;

stigmas prominent, strongly curled (circinate) to erect, connate basally, pale green or white, not lobed, 4–10 mm, uniformly thin;

pedicel deflexed or recurved, rarely erect, angled, 2–4(–5) cm.

Fruits

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

baccate, greenish or whitish, ovoid-globose, angles less prominent when mature, 1–1.5 cm diam., pulpy but not juicy.

2n

= 10.

Trillium sessile

Trillium catesbaei

Phenology Flowering spring (Mar–early May). Flowering spring–summer (late Mar–early Jun).
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 Acid soils, open dry or rich woods, laurel and rhododendron thickets, cove forests
Elevation 100–300 m (300–1000 ft) 50–800 m (200–2600 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.)

Elliott, author of Trillium catesbaei, apparently recognized one of its forms separately as T. nervosum. This name is still mentioned in British horticultural and botanical literature, but it is rarely found in U.S. literature. North American botanists treat T. nervosum as a synonym of T. catesbaei.

Plants of Trillium catesbaei from deep coves in South Carolina tend to have petals that are deeper pink and longer and wider than those of many other populations.

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

Source FNA vol. 26, p. 115. FNA vol. 26, p. 96.
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. 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. stamineum, T. sulcatum, T. underwoodii, T. undulatum, T. vaseyi, T. viride, T. viridescens
Synonyms T. affine, T. nervosum, T. stylosum
Name authority Linnaeus: Sp. Pl. 1: 340. (1753) Elliott: Sketch Bot. S. Carolina 1: 429. (1817)
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