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bent trillium, declined trillium, drooping trillium, nodding wakerobin

giant purple wakerobin, narrow petal wakerobin, narrow-petal trillium

Habit Plants tall, very robust.
Rhizomes

somewhat erect, thick, praemorse.

erect, brownish, thick, somewhat compressed-thickened, praemorse, not brittle.

Scapes

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

1–2, round in cross section, 2.5–6 dm.

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.

held well above ground, spreading horizontally, subsessile;

blade very sparsely mottled with dark greenish brown or rarely all green, mottling becoming obscure with age, broadly ovate, 10–22 × 8.7–15 cm, not glossy, often narrowed to falsely petiolate, very short, and narrowly cuneate base 10–20 mm, apex obtuse.

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.

erect, odor spicy-musty, musty, or fetid;

sepals conspicuous, spreading, often resting on bracts, maroon to green, linear to oblong-lanceolate, 35–47 × 8–10 mm, margins flat, entire, apex acute;

petals long-lasting, erect, ± connivent, ± concealing stamens and ovary and partially obscuring stamens, dark purple to red-purple, not spirally twisted, veins obscure, linear, 5–10 × 0.7–1.4 cm, 8–10 times longer than wide, glossy, thick-textured, base linear, margins entire, at first flat but inrolling with age, apex variously acute-obtuse;

stamens erect, 12–22 mm;

filaments dark maroon, 2–4 mm, slender, widest at base;

anthers erect, straight, purple, 12–18 mm, dehiscence introrse;

connectives purple, slightly extended 1–1.5 mm beyond anther sacs;

ovary dark, ovoid-ellipsoid, 6-angled toward apex, 7.5–12 mm;

stigmas erect, divergent-recurved, distinct, purple, sessile, awl-shaped, thickly subulate, 5 mm, thick, fleshy.

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.

dark purple, fragrance unknown, subglobose, 6-angled, almost winged, fleshy.

2n

= 10.

= 10.

Trillium flexipes

Trillium angustipetalum

Phenology Flowering spring (Apr–early Jun). Flowering spring–early summer (Mar–Jun).
Habitat Rich wooded slopes, floodplains in deciduous forests, especially over limestone Big-tree (Sequoiadendron) groves and other mixed coniferous-deciduous flatwoods, slightly damper depressions under maples and deciduous shrubs, coastal mountains, oak (Quercus) groves in ravines and otherwise quite arid, almost treeless chaparral, wooded canyon slopes, dense woods near streams
Elevation 100–600 m (300–2000 ft) 30–200 m (100–700 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
CA
[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.)

Trillium angustipetalum occurs in the Sierra Nevada from Fresno County north to Placer County (J. D. Freeman 1975). It is disjunct in the coastal mountains and hills of Santa Barbara and San Luis Obispo counties.

B. D. Ness (1993) listed Trillium kurabayashii as a synonym of T. angustipetalum. In bract orientation, color, and texture, and in petal shape, the two are quite different and certainly not the same species. Cytologist Masataka Kurabayashi found chromosomal differences between the two species (reported by J. D. Freeman 1975).

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

Source FNA vol. 26, p. 99. FNA vol. 26.
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. 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. viride, T. viridescens
Synonyms T. declinatum, T. gleasonii T. sessile var. angustipetalum, T. giganteum var. angustipetalum
Name authority Rafinesque: Autik. Bot., 133. (1840) (Torrey) J. D. Freeman: Brittonia 27: 55. (1975)
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