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longbract wakerobin, Underwood's trillium

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

Rhizomes

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

short, thick, praemorse.

Scapes

1–2, round in cross section, 0.8-2 dm, slender to stout, glabrous.

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

Bracts

usually drooping, often touching ground in early anthesis, sessile;

blade pale silvery green, strongly mottled in 3 or more shades of dark green and bronze, sometimes maroon, mottling becoming obscure with age, ovate-lanceolate to obovate, 6.5–12 × 5–7.8 cm, margins of distal 1/3 straight from rounded base to apex, apex acuminate.

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 fetid, especially when first open;

sepals displayed above bracts, spreading, green or purple on adaxial surface, lanceolate, 4.5–5 × 8–12 mm, margins entire, flat, apex rounded-acute;

petals long-lasting, erect-spreading, ± connivent, ± concealing stamens and ovary or at least partially obscuring stamens, tips ± incurved, dark maroon-red, or purplish red, brownish maroon, or yellowish green, not spirally twisted, oblanceolate to elliptic, 3–5.5+ × 1–1.5 cm, usually 3–4 times longer than wide, thick-textured, margins entire, apex acute;

stamens ± erect to weakly incurved, 14–17 mm;

filaments purple, 1–2 mm;

anthers 8–15 mm, thick, dehiscence latrorse;

connectives brown-purple, straight, extended 1–2 mm beyond anther sacs, apex somewhat acute;

ovary purple, ellipsoid, 6-angled, 6.3–11 mm;

stigmas erect, abruptly recurved upon ovary, distinct, purplish, linear, 1.5–5 mm, slightly thickened basally, 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

baccate, purple-black to dull greenish maroon, odorless, ovoid to obovoid, 6-angled (-ridged), 0.7–1 cm diam., pulpy, not juicy.

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

2n

= 10.

Trillium underwoodii

Trillium erectum

Phenology Flowering mid winter–spring (late Feb–mid Apr).
Habitat Rich to dryish deciduous forests of mature or second-growth timber, dominated by oaks or with beech-oaks, occasionally with scattered pines present, flat ground along streams where soil can be fairly moist, rich clay or sand
Elevation 100–200 m (300–700 ft)
Distribution
from FNA
AL; FL; GA
[WildflowerSearch map]
[BONAP county map]
from USDA
e North America
[WildflowerSearch map]
[BONAP county map]
Discussion

Trillium underwoodii can cause considerable confusion for the beginning student of the genus. In some ways it closely resembles a small-statured T. cuneatum. As T. underwoodii continues to expand after flowering, it may become somewhat taller and less “ground hugging,” and it then appears similar to a smaller plant of T. decipiens, which grows in parts of the same range, especially when its bracts do not touch the ground at anthesis. It also has vague similarities to T. reliquum, with which it grows sympatrically in parts of its range. Care should be taken to observe the details of floral structure accurately.

Distribution of Trillium underwoodii is much more restricted than that given by J. K. Small (1933), who indicated a range extending from Alabama to North Carolina and Arkansas.

(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. Petals usually red, maroon, or dark purple.
var. erectum
1. Petals white.
var. album
Source FNA vol. 26, p. 116. 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. 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. 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. erectum var. album, T. erectum var. erectum
Name authority Small: Bull. Torrey Bot. Club 24: 172. (1897) Linnaeus: Sp. Pl. 1: 340. (1753)
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