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giant purple wakerobin, giant trillium, giant wakerobin, sessile trillium, small-flower trillium

birthwort, red trillium, red wakerobin, stinking Benjamin, stinking willie, wake-robin

Rhizomes

± erect, brownish, somewhat compressed-thickened, superficially bulblike, praemorse, not brittle.

short, thick, praemorse.

Scapes

1–3, green, round in cross section, 2–6.5 dm, robust.

1–2, often with numerous offsets forming heavy clumps, round in cross section, 1.5–6 dm, ± robust, glabrous.

Bracts

held well above ground, sessile (narrowing of bract blade may give bract subsessile appearance);

blade densely to weakly mottled in dark brownish green, mottling becoming more obscure to absent as bract matures, broadly ovate, 7–17.6 × 7.4–17.7 cm, not glossy, apex obtuse-rounded.

sessile;

blade bright green, lacking dark pigmentation, major veins prominent, broadly rhombic to ovate-rhombic, 5–20 × 5–20 cm, about as broad as long, widest near middle, base attenuate, apex acuminate.

Flower

erect, odor roselike, spicy;

sepals spreading-ascending above bracts, green, lanceolate, 35–65 × 7–12 mm, margins entire, flat, apex obtusely rounded;

petals long-lasting, erect, connivent, ± concealing stamens and ovary, yellow, bronze, maroon, brown, deep purple, reddish brown, pink, dark purplish red, purplish bronze, rarely greenish white, not spirally twisted, veins not engraved, oblanceolate to obovate, 6.5–10 × 1.5–2.5 cm, thick-textured, base cuneate, margins entire, apex variably acute to almost truncate, erose;

stamens erect, purplish, 17–26 mm;

filaments purple, ca. 4 mm, widest at base, much shorter than anther sacs;

anthers erect, straight, ± purple-brown, 13–22 mm, dehiscence introrse;

connectives purple, straight, extended ca. 1–1.5 mm beyond anther sacs;

ovary purple, ovoid, 6-angled, 6–12 mm;

stigmas small, divergent or erect, distinct, purple, subulate, 4–8 mm, not fleshy.

erect, ascending, or proximal to but above bracts, odor fetid, like a wet dog;

perianth open, flat;

sepals flat to sulcate apically, green, often streaked or overlain with maroon, occasionally entirely dark maroon, lanceolate-acuminate, 10–50 mm, equaling petals, ± 1/2 petal width, texture leafy, margins entire, apex acuminate;

petals spreading, carried in same plane as sepals or ascending slightly, dark reddish brown, maroon, purple, or white, sometimes pale yellow, major adaxial veins prominent and appearing somewhat engraved, usually flat, lanceolate, ovate-lanceolate, or occasionally ovate, 1.5–5 × 1–3 cm, 2 times sepal width, widest near base, heavy-textured, apex acuminate;

stamens erect to slightly recurved, 5–15 mm;

filaments white, pinkish, or dark purple, ± equaling anthers, but variable within local populations, thin;

anthers erect or weakly recurving, dark maroon, grayish maroon, or yellowish, strongly yellow when pollen exposed, 5–12 mm, dehiscence introrse;

ovary dark purple to maroon, even in white-flowered forms, ovoid, elliptic to globose, 6-angled, angles forming very low ridges when fruit is ripe, 5–10 mm, broadly attached at base;

stigmas recurved, distinct, dark purple, not lobed adaxially, subulate, short, 3–7 mm, ca. 1/2 or less length of ovary at anthesis, fleshy;

pedicel straight, erect, or somewhat declined but not strongly recurved below bracts, 1–10+ cm.

Fruits

red-purple, fragrance not reported, ovoid, obscurely 6-angled, 2.5–3 cm, pulpy, juicy.

dark maroon, weakly fragrant of fruit, ± globose to slightly pyramidal, 1–1.6 × 1–1.5 cm, juicy.

2n

= 10.

= 10.

Trillium chloropetalum

Trillium erectum

Distribution
from FNA
CA
[WildflowerSearch map]
[BONAP county map]
from USDA
e North America
[WildflowerSearch map]
[BONAP county map]
Discussion

Varieties 2 (2 in the flora).

J. D. Freeman (1975) considered that Trillium chloropetalum differs from T. albidum in having introrse (not latrorse) anther sacs, and that the purple pigments present on anther and ovary tissue here are absent in T. albidum. In some places, hybridization between the two certainly has occurred, and a complete range of intergrades exists.

This species merits further study. The following varieties are only weakly differentiated and perhaps ought to be dropped.

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

Varieties 2 (2 in the flora).

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

Key
1. Petal tissue always with yellow pigments, often present with other pigments; petals yellow, greenish yellow, greenish purple, or bronze-green or brown.
var. chloropetalum
1. Petal tissue lacking yellow pigments; petals purple, reddish purple, garnet red, pink, or greenish white.
var. giganteum
1. Petals usually red, maroon, or dark purple.
var. erectum
1. Petals white.
var. album
Source FNA vol. 26. FNA vol. 26, p. 98.
Parent taxa Liliaceae > Trillium > subg. Phyllantherum Liliaceae > Trillium > subg. Trillium
Sibling taxa
T. albidum, T. angustipetalum, T. catesbaei, T. cernuum, 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
T. albidum, T. angustipetalum, T. catesbaei, T. cernuum, T. chloropetalum, T. cuneatum, T. decipiens, T. decumbens, T. discolor, 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
Subordinate taxa
T. chloropetalum var. chloropetalum, T. chloropetalum var. giganteum
T. erectum var. album, T. erectum var. erectum
Synonyms T. sessile var. chloropetalum, T. giganteum var. chloropetalum
Name authority (Torrey) Howell: Fl. N.W. Amer., 661. (1902) Linnaeus: Sp. Pl. 1: 340. (1753)
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