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longbract wakerobin, Underwood's trillium

Barksdale trillium, furrowed wakerobin, southern red trillium

Rhizomes

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

horizontal–slightly erect, thick, praemorse.

Scapes

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

1–4+, round in cross section, 3–7 dm, 2–2.5 times as long as bract, stout, 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.

subsessile;

blade obovate to broadly elliptic, 13–20 × 8–22 cm, not glossy, 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.

facing outward at right angle to pedicel, above bracts, odor faintly musty, like fresh fungus;

perianth gaping, strongly 3-dimensional;

sepals spreading, usually streaked or entirely purplish maroon, occasionally entirely green except on margins, elliptic, 15–38 × 9–15 mm, margins entire, apex strongly sulcate-acuminate;

petals carried somewhat forward to recurved-spreading in distal 1/2, usually dark reddish maroon to purplish, rarely cream to soft yellow, pink, white, or 2-colored, heavy-veined, ovate to broadly ovate-overlapping, 1.8–5 × 1–3 cm, heavy-textured, apex acuminate, rarely somewhat sulcate;

stamens erect, ± equaling or slightly longer than ovary, 15–18 mm;

filaments purple to white, 3–5 mm, slender;

anthers straight, purplish to yellow, 5–12 mm, thick, dehiscence introrse;

connectives equaling or ± shorter than anther sacs;

ovary usually dark purple, globose to flask-shaped, 6-angled, 14–18 mm, broadly attached basally;

stigmas prominent, recurved, distinct, purple, not lobed adaxially, basally thickened, gradually tapered, 2–5 mm, fleshy;

pedicel usually stiffly erect (rarely almost horizontal above bracts), straight, reflexed ± 90° at tip, 6–11 cm.

Fruits

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

red, fragrance of fresh mushrooms, ± globose to pyramidal, 1.5–3 × 1.2–2.8 cm, juicy to pulpy.

2n

= 10.

Trillium underwoodii

Trillium sulcatum

Phenology Flowering mid winter–spring (late Feb–mid Apr). Flowering mid spring (Apr–May).
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 Rich mesic woodlands, especially moist north- or east-facing slopes, wooded ledges and stream banks on neutral to slightly acid soil
Elevation 100–200 m (300–700 ft) 300–400 m (1000–1300 ft)
Distribution
from FNA
AL; FL; GA
[WildflowerSearch map]
[BONAP county map]
from FNA
AL; GA; KY; NC; TN; VA; WV
[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.)

Trillium sulcatum is present mainly on the Cumberland Plateau and is absent from the Great Smoky Mountains and the southern Blue Ridge Mountains.

T. S. Patrick (1984) described Trillium sulcatum flowers as “relatively small and turned downward.” This is true of plants from the type locality; however, in most plants of the Cumberland Plateau, the flowers are quite large and flattened, and the petals are recurved distally and face outward.

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

Source FNA vol. 26, p. 116. FNA vol. 26, p. 104.
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. 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. underwoodii, T. undulatum, T. vaseyi, T. viride, T. viridescens
Name authority Small: Bull. Torrey Bot. Club 24: 172. (1897) T. S. Patrick: Brittonia 36: 27, figs. 1–4. (1984)
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