Trillium albidum
Trillium luteum
giant trillium, giant white wakerobin, sessile trillium, smallflower trillium, white toadshade
wax trillium, yellow toadshade, yellow trillium, yellow wakerobin
horizontal, ± erect, brown, superficially bulblike, short, thick, not brittle.
horizontal, brownish, short, thick, praemorse, not brittle.
often several from same rhizome terminus, round in cross section, 2.2–5.8 dm, stout.
1–4, round in cross section, 1.4–4 dm, stout, glabrous.
held well above ground, sessile;
blade weakly mottled with scattered, darker green spots, mottling often fading later in season, broadly ovate, 10–20 × 12–15 cm, not glossy, base rounded, apex obtuse.
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.
borne directly upon bracts, erect, fragrance roselike;
sepals conspicuous, spreading, displayed above bracts, pale green, lanceolate, 30–65 × 12–15 mm, margins entire, apex acute;
petals long-lasting, usually erect or slightly spreading, ± connivent, ± concealing stamens and ovary basally, white to creamy white, rarely soft pinkish rose near base, veins prominent but not engraved, not spirally twisted, obovate, more lanceolate in young plants, 4.8–8 × 2.2–3 cm, widest at or just above middle, ± thick-textured, base cuneate, margins entire, ± flat, apex rounded to acute;
stamens erect, greenish white, 15–25 mm;
filaments whitish green, 3–4 mm, slender;
anthers erect, straight, yellow, 11–20 mm, dehiscence latrorse;
connectives straight, extended ca. 1 mm beyond anther sacs, rounded;
ovary green or occasionally purple, ovoid, rounded 6-gonal, 6–11 mm;
stigmas erect to spreading, distinct, sessile, subulate, 4–7 mm, thin distally.
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.
green or purplish green, fragrance unknown, ovoid to globose, pulpy, juicy.
green to greenish white, occasionally with dark streaks, odor not reported, ovoid, 6-angled, 3.5 × 2 cm, pulpy.
= 10.
Trillium albidum
Trillium luteum
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.)
CA
OR
WA
Flora NW
PNW Herbaria
WildflowerSearch
iNaturalist
USDA Plants Database
