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

painted lady, painted trillium, painted wakerobin, trille ondulé

Rhizomes

short, thick, praemorse.

horizontal, short, stout, ± praemorse.

Scapes

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

1–3, dark greenish maroon, round in cross section, 1.1–4 dm, glabrous.

Bracts

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.

strongly petiolate;

blade dark green over maroon, main veins prominent, ovate to long-acuminate, 12–18 × 8–20 cm, ± glossy, base above petiole rounded, apex acuminate;

petiole 4–17 mm.

Flower

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.

opening above bracts, erect, odor unknown;

sepals conspicuous, spreading, wine red to dull maroon green, rarely white-striated, lanceolate-acuminate, 13–37 × 4–10 mm, margins entire, apex acuminate;

petals spreading, white, with distinct, inverted, V-shaped, dark-red mark basally, the red radiating outward along major veins, or white and lacking red marks, veins not engraved, oblong-ovate, occasionally lanceolate, usually widest just above middle, 2–5 × 1–2 cm, base tapering very gradually to attachment, margins not undulate basally, undulate apically, apex somewhat rapidly acuminate;

stamens straight, 8–12 mm;

filaments pink or white, equaling or longer than anthers, slender;

anthers erect or slightly spreading, white or pink, 2–7 mm, thin, dehiscence extrorse;

connectives pink, equaling anther sac;

ovary fully exposed, white, pink tipped, obtusely 3-angled, becoming obscurely angled-rotund in cross section, 3–10 mm, broadly attached;

stigmas ascending, barely connate basally, then strongly recurved, white, ± linear, 3–10 mm, uniformly thin;

pedicel erect, 2–5 cm.

Fruits

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

quickly deciduous upon ripening, scarlet, obscurely 3-angled to cylindrical, 1–2 cm, fleshy, juicy.

2n

= 10.

= 10.

Trillium erectum

Trillium undulatum

Phenology Flowering late spring–early summer (late Apr–Jun).
Habitat Deep acid humus of pine, spruce, hemlock, oak, mixed deciduous-coniferous woods, rhododendron or mountain laurel thickets in s range, almost any acidic forested situation n and ne, often around old Pinus strobus stumps in white birch-red maple-white pine second-growth woods in n range, prefers deep shade except at high elevations in range, not usually found on limestone-derived or basic soils unless in very deep acid humus
Elevation 10–1800 m (0–5900 ft)
Distribution
from USDA
e North America
[WildflowerSearch map]
[BONAP county map]
from FNA
CT; GA; KY; MA; MD; ME; MI; NC; NH; NJ; NY; OH; PA; RI; SC; TN; VA; VT; WV; NB; NS; ON; PE; QC
[WildflowerSearch map]
[BONAP county map]
Discussion

Varieties 2 (2 in the flora).

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

Several forms of Trillium undulatum have been described. One, forma enotatum T. S. Patrick, lacks the usual red, V-shaped petal markings. Other named forms have green petals, extra leaves or petals, and deformities suggesting a mycoplasma infection as in Trillium grandiflorum.

This difficult-to-cultivate species has been reported from Wisconsin, but it cannot be accepted as native there.

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

Key
1. Petals usually red, maroon, or dark purple.
var. erectum
1. Petals white.
var. album
Source FNA vol. 26, p. 98. FNA vol. 26, p. 105.
Parent taxa Liliaceae > Trillium > subg. Trillium 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. 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. 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. vaseyi, T. viride, T. viridescens
Subordinate taxa
T. erectum var. album, T. erectum var. erectum
Synonyms T. erythrocarpum
Name authority Linnaeus: Sp. Pl. 1: 340. (1753) Willdenow: Ges. Naturf. Freunde Berlin Neue Schriften 3: 422. (1801)
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