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longbract wakerobin, Underwood's trillium

green trillium, wood wakerobin

Rhizomes

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

horizontal, brownish, short, slender to stout, praemorse, not brittle.

Scapes

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

1–3, round in cross section, 2.3–3.4+ dm, ± slender, smooth to scabrous below bracts.

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.

held well above ground, sessile;

blade green to bluish green, weakly mottled, rarely unmottled, mottling becoming obscure with age, adaxial surface covered with numerous stomata easily visible under a lens, occasionally visible as tiny white dots to the naked eye, narrowly to broadly elliptic, 8–20.5 × 5–8 cm, not glossy, apex blunt to rounded-acute.

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, odor of decayed fruit;

sepals displayed above bracts, widely spreading, distal 1/2 often weakly declined, green, lanceolate-acute, 28–60 × 7–9 mm, margins entire, apex acute;

petals long-lasting, erect to widely spreading, ± connivent, ± concealing stamens and ovary, green, yellowish green, yellow, or variously purple streaked throughout, especially basally (rarely all purplish green), not spirally twisted, narrowly spatulate to linear-spatulate, 3.5–6.8 × 0.5–1.5 cm, widest above middle, thick-textured, base narrowed and thickened, ± forming claw, margins entire, apex obtuse, lacking nipple;

stamens relatively straight-erect to slightly incurved, 15–25 mm;

filaments brown-olive, 3–5.5 mm, dilated basally;

anthers erect, straight, olive-brown or purplish, 8–21 mm, ± slender, dehiscence introrse-latrorse;

connectives olive, straight, very slightly (± 0.5 mm) extended beyond sacs;

ovary greenish basally, olive-purplish distally, ellipsoid to ovoid, deeply angled, 5–12 mm;

stigmas spreading-erect, recurved, distinct, sessile, olive or purplish, subulate, 5–10 mm, somewhat fleshy.

Fruits

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

greenish white, odorless, ovoid, angled, 1–1.5 cm, somewhat pulpy, not juicy.

2n

= 10.

Trillium underwoodii

Trillium viride

Phenology Flowering mid winter–spring (late Feb–mid Apr). Flowering spring (late 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 woods, bluffs, rocky hillsides with some limestone outcrops, woodsy, humusy soil over fairly stiff, clayey substrate
Elevation 100–200 m (300–700 ft) 100–200 m (300–700 ft)
Distribution
from FNA
AL; FL; GA
[WildflowerSearch map]
[BONAP county map]
from FNA
IL; MO
[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 viride has long been confused with T. luteum of the Smoky Mountain region, though it is far more slender and delicate than T. luteum. Because the pallid forms and so-called albinos of many other sessile trilliums described in written accounts sound much like the description of this plant, early authors ascribed far too wide a range to T. viride. The plant is closely limited to the woodlands of the counties adjacent to the Missouri River in northeastern Missouri and southern Illinois.

Although the ranges of Trillium viride and the very similar T. viridescens do not overlap, both species grow in Missouri, and authors earlier than J. D. Freeman (1975) frequently combined the two as a single species. If all other means of identification fail, the prevalence of numerous stomates on the adaxial bract surface, seen under magnification, will always distinguish T. viride.

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

Source FNA vol. 26, p. 116. FNA vol. 26, p. 116.
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. 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. sulcatum, T. underwoodii, T. undulatum, T. vaseyi, T. viridescens
Name authority Small: Bull. Torrey Bot. Club 24: 172. (1897) L. C. Beck: Amer. J. Sci. Arts 11: 178. (1826)
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