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bent trillium, declined trillium, drooping trillium, nodding wakerobin

Idaho trillium, long-petioled trillium, petioled wakerobin, purple trillium, purple wakerobin, round-leaf trillium

Rhizomes

somewhat erect, thick, praemorse.

± erect, often very deep, praemorse.

Scapes

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

typically 1, vertical but mostly subterranean, round in cross section, 0.4–1.7 dm, robust, glabrous.

Bracts

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.

just at or slightly above soil, long-petiolate;

blade medium green, not mottled, ovate to elliptic, 7–14 × 5.5–10.2 cm, not glossy, apex obtuse or rounded;

petiole arising from scape apex at or near ground surface, 5–12 cm;

bract and petiole strongly resembling leaves of Plantago.

Flower

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.

in axil of bracts at or near ground level, ± erect, odor unknown;

sepals erect to widely spreading, often weakly recurved near middle, green, oblong-elliptic to oblanceolate, 22–47 × 7–10 mm, margins entire, apex acute;

petals long-lasting, ± connivent, ± concealing stamens and ovary, or erect-spreading early then ± connivent, erect to incurved, light maroon-red, purple, or greenish to yellowish, not spirally twisted, flat, linear-lanceolate, 3–5.5 × 0.4–1 cm, thick-textured, margins entire, apex acute;

stamens erect, (15–) 22–30 mm;

filaments olive, (3–)5–7 mm, slender;

anthers straight, brown or olive, 16–20 mm, slender, dehiscence latrose;

connectives yellow or orange, ± not extending beyond anther sacs;

ovary white, greenish, purplish distally, ovoid, sharply angled, 4–9 mm;

stigmas erect, divergent, distinct, purple or olive, linear-subulate, 7–20 mm, apex somewhat recurved.

Fruits

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.

fragrance not reported, ovoid, strongly angled/winged, ca. 1 cm, pulpy, moist.

2n

= 10.

= 10.

Trillium flexipes

Trillium petiolatum

Phenology Flowering spring (Apr–early Jun). Flowering spring (early Apr–late May).
Habitat Rich wooded slopes, floodplains in deciduous forests, especially over limestone Lower rocky hillsides just above stream flats, under brush, edges of coniferous and deciduous forests, open grassy glades, river-flats, wet, seasonally swampy ground and edges of sloughs
Elevation 100–600 m (300–2000 ft) 400–1400 m (1300–4600 ft)
Distribution
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]
from FNA
ID; OR; WA
[WildflowerSearch map]
[BONAP county map]
Discussion

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. 99. FNA vol. 26, p. 113.
Parent taxa Liliaceae > Trillium > subg. Trillium 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. 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
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. 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 Rafinesque: Autik. Bot., 133. (1840) Pursh: Fl. Amer. Sept. 1: 244. (1814)
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