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Blue Ridge wakerobin, twisted trillium

giant purple wakerobin, narrow petal wakerobin, narrow-petal trillium

Habit Plants tall, very robust.
Rhizomes

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

erect, brownish, thick, somewhat compressed-thickened, praemorse, not brittle.

Scapes

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

1–2, round in cross section, 2.5–6 dm.

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, spreading horizontally, subsessile;

blade very sparsely mottled with dark greenish brown or rarely all green, mottling becoming obscure with age, broadly ovate, 10–22 × 8.7–15 cm, not glossy, often narrowed to falsely petiolate, very short, and narrowly cuneate base 10–20 mm, apex obtuse.

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 spicy-musty, musty, or fetid;

sepals conspicuous, spreading, often resting on bracts, maroon to green, linear to oblong-lanceolate, 35–47 × 8–10 mm, margins flat, entire, apex acute;

petals long-lasting, erect, ± connivent, ± concealing stamens and ovary and partially obscuring stamens, dark purple to red-purple, not spirally twisted, veins obscure, linear, 5–10 × 0.7–1.4 cm, 8–10 times longer than wide, glossy, thick-textured, base linear, margins entire, at first flat but inrolling with age, apex variously acute-obtuse;

stamens erect, 12–22 mm;

filaments dark maroon, 2–4 mm, slender, widest at base;

anthers erect, straight, purple, 12–18 mm, dehiscence introrse;

connectives purple, slightly extended 1–1.5 mm beyond anther sacs;

ovary dark, ovoid-ellipsoid, 6-angled toward apex, 7.5–12 mm;

stigmas erect, divergent-recurved, distinct, purple, sessile, awl-shaped, thickly subulate, 5 mm, thick, fleshy.

Fruits

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

dark purple, fragrance unknown, subglobose, 6-angled, almost winged, fleshy.

2n

= 10.

= 10.

Trillium stamineum

Trillium angustipetalum

Phenology Flowering spring (late Mar–mid May). Flowering spring–early summer (Mar–Jun).
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 Big-tree (Sequoiadendron) groves and other mixed coniferous-deciduous flatwoods, slightly damper depressions under maples and deciduous shrubs, coastal mountains, oak (Quercus) groves in ravines and otherwise quite arid, almost treeless chaparral, wooded canyon slopes, dense woods near streams
Elevation 50–200 m (200–700 ft) 30–200 m (100–700 ft)
Distribution
from FNA
AL; MS; TN
[WildflowerSearch map]
[BONAP county map]
from FNA
CA
[WildflowerSearch map]
[BONAP county map]
Discussion

Trillium angustipetalum occurs in the Sierra Nevada from Fresno County north to Placer County (J. D. Freeman 1975). It is disjunct in the coastal mountains and hills of Santa Barbara and San Luis Obispo counties.

B. D. Ness (1993) listed Trillium kurabayashii as a synonym of T. angustipetalum. In bract orientation, color, and texture, and in petal shape, the two are quite different and certainly not the same species. Cytologist Masataka Kurabayashi found chromosomal differences between the two species (reported by J. D. Freeman 1975).

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

Source FNA vol. 26, p. 115. FNA vol. 26.
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. 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. stamineum, T. sulcatum, T. underwoodii, T. undulatum, T. vaseyi, T. viride, T. viridescens
Synonyms T. sessile var. angustipetalum, T. giganteum var. angustipetalum
Name authority Harbison: Biltmore Bot. Stud. 1: 23. (1901) (Torrey) J. D. Freeman: Brittonia 27: 55. (1975)
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