Trillium viride
Trillium luteum
green trillium, wood wakerobin
wax trillium, yellow toadshade, yellow trillium, yellow wakerobin
horizontal, brownish, short, slender to stout, praemorse, not brittle.
horizontal, brownish, short, thick, praemorse, not brittle.
1–3, round in cross section, 2.3–3.4+ dm, ± slender, smooth to scabrous below bracts.
1–4, round in cross section, 1.4–4 dm, stout, glabrous.
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.
held well above ground, sessile;
blade mottled, mottling becoming more obscure as growth matures, shape variable, ovate-elliptic to ± orbicular-acuminate, 6.5–17 × 6.5–9.8 cm, not glossy, apex acuminate to long-acuminate.
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.
erect, odor strongly lemony;
sepals displayed above bracts, widely spreading, green, oblong-lanceolate, lanceolate, or oblong-elliptic, 22–47 × 8–9 mm, margins entire, apex distinctly rounded-acute;
petals long-lasting, erect, ± connivent, ± concealing stamens and ovary, greenish yellow to lemon yellow, not spirally twisted, not clawed, elliptic-lanceolate, lanceolate, or oblanceolate, 3.4–6.6 × 1–2.1 cm, thick-textured, widest near base, margins entire, tapering to long-acuminate apex;
stamens erect, 11–18 mm;
filaments greenish white, 1.5–2 mm, basally dilated;
anthers erect, straight, yellow, 9–16 mm, dehiscence introrse (or appearing lateral);
connectives green, straight, broad, extending only slightly (to 0.5 mm) or not at all beyond anther sacs;
ovary pale green, ovoid to globose, 6-angled, 5–8 mm;
stigmas erect, barely spreading, distinct, greenish white, sessile, linear to subulate, 3–4 mm, fleshy.
greenish white, odorless, ovoid, angled, 1–1.5 cm, somewhat pulpy, not juicy.
green to greenish white, occasionally with dark streaks, odor not reported, ovoid, 6-angled, 3.5 × 2 cm, pulpy.
= 10.
= 10.
Trillium viride
Trillium luteum
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.)
Botanists have been confused by Trillium luteum for a long time. Some, such as A. E. Radford et al. (1968), appear to regard it as a form of T. cuneatum, while others confuse it with T. viride, a more western species. Early botanists confused T. luteum with the occasional individual or very local larger population of pallid color forms of other species. Trillium cuneatum rather frequently produces green, yellowish green, or pale lemon yellow forms (but with a cuneate larger and wider petal) that mimic T. luteum. These forms, when growing with T. luteum, hybridize, leading to so many intergrades that many plants cannot be placed in either species with any confidence. For these reasons, almost no work older than J. D. Freeman’s (1975) can be used reliably to plot distribution of T. luteum.
In some parts of their ranges, Trillium luteum and T. cuneatum do not grow together. Trillium luteum is abundant in eastern Tennessee, extending a short distance into North Carolina and Georgia. Trillium cuneatum is rare or absent from this region except along the Little Tennessee River (J. D. Freeman 1975).
Trillium luteum has escaped and become established along the Grand and Saint Joseph rivers and elsewhere in Michigan, near Kingston and Grimsby, Ontario (J. K. Morton pers. comm.), and probably elsewhere.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
IL Wildflowers
MO Plants
WildflowerSearch
iNaturalist
USDA Plants Database
