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green trillium, wood wakerobin

bent trillium, declined trillium, drooping trillium, nodding wakerobin

Rhizomes

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

somewhat erect, thick, praemorse.

Scapes

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

1–several from single rhizome, round in cross section, 2–5 dm, glabrous.

Bracts

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.

sessile;

blade medium green without red or maroon undertones, rhombic, 7–25 × 7–25 cm, frequently wider than long, base attenuate from just above middle, apex acuminate.

Flower

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.

flexed ca. 90° on summit of pedicel to face outward rather than upward, or variously carried on strongly declined pedicels;

sepals weakly recurved, green, lanceolate, 14–45 mm, shorter than or barely equaling petals, margins entire, apex acuminate;

petals flat or recurved in distal 1/2, creamy white, not 2-colored, veins conspicuously engraved, ovate-lanceolate to broadly ovate, 2–5 × 1–4 cm, texture heavy, margins entire, apex acute;

stamens large, ± erect, 9–23 mm;

filaments white, less than 1/2 anther length, thin;

anthers straight or very slightly recurving, creamy white or yellow, 5–18 mm, thick, dehiscence ± introrse;

ovary white, ovoid to flask-shaped, strongly 6-angled, 5–16 × 4–12 mm, widely attached basally;

stigmas recurved, distinct but closely grouped, white, not lobed adaxially, linear-subulate, short, thick, 4–13 mm, ± equaling ovary, fleshy;

pedicel stiffly erect, carried horizontally, or declined beneath bracts, rarely recurved, 4–12 cm.

Fruits

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

baccate, rosy red to purplish, fragrant of ripe fruit, ovoid to somewhat pyramidal at summit, strongly angled, 2–3.5 × 1–3 cm, very juicy at maturity.

2n

= 10.

= 10.

Trillium viride

Trillium flexipes

Phenology Flowering spring (late Apr–May). Flowering spring (Apr–early Jun).
Habitat Rich woods, bluffs, rocky hillsides with some limestone outcrops, woodsy, humusy soil over fairly stiff, clayey substrate Rich wooded slopes, floodplains in deciduous forests, especially over limestone
Elevation 100–200 m (300–700 ft) 100–600 m (300–2000 ft)
Distribution
from FNA
IL; MO
[WildflowerSearch map]
[BONAP county map]
from FNA
AL; DE; IA; IL; IN; KY; MI; MN; MO; NY; OH; PA; SD; TN; VA; WI; WV; ON
[WildflowerSearch map]
[BONAP county map]
Discussion

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.)

Although there are no named varieties of Trillium flexipes, many forms exist and at least one has been named, forma walpolei (Farwell) Fernald. F. W. Case and G. L. Burrows (1962) mapped the occurrence of forma walpolei for Michigan and found it to occur only along the contact zone between T. flexipes and T. erectum. F. W. Case and R. B. Case (1993) crossed typical T. erectum and T. flexipes to produce identical color variations as occur in these wild, mixed-species populations. I consider this form to be a hybrid expression. Some of the hybrids have petals colored proximally and white distally, superficially resembling T. undulatum. Dried specimens, when hastily examined, resemble T. undulatum superficially and probably account for reports of that species from locations near Ann Arbor, Michigan, and various places in Indiana and Illinois, all of which are well out of the range of T. undulatum.

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

Source FNA vol. 26, p. 116. FNA vol. 26, p. 99.
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. underwoodii, T. undulatum, T. vaseyi, T. viridescens
T. albidum, T. angustipetalum, T. catesbaei, T. cernuum, T. chloropetalum, T. cuneatum, T. decipiens, T. decumbens, T. discolor, T. erectum, 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
Synonyms T. declinatum, T. gleasonii
Name authority L. C. Beck: Amer. J. Sci. Arts 11: 178. (1826) Rafinesque: Autik. Bot., 133. (1840)
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