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nodding trillium, nodding wakerobin, trille penché, whip-poor-will-flower

brook trillium, brook wake-robin

Rhizomes

short, thick.

horizontal, short, praemorse, fleshy.

Scapes

1–2(–3), round in cross section, 1.5–4+ dm, slender, glabrous.

1–2, round in cross section, 0.4–1.5 dm, slender, glabrous.

Bracts

often overlapping, sessile or with a barely noticeable, petiolelike base, umbrellalike;

blade bright green without red tones, broadly rhombic-ovate to suborbicular, 5–15 × 6–15+ cm, base attenuate, apex acuminate.

distinctly petiolate;

blade bluish green, occasionally with silvery green pattern along major veins, ovate-lanceolate, 1.5–8 × 0.8–6 cm, somewhat thick-textured, glossy, weakly to strongly cordate basally, apex long-acuminate;

petiole (0.5–)1–3(–6) cm.

Flower

usually hidden beneath bracts, nodding, odorless;

sepals spreading, green, lanceolate-ovate, 9–30 mm, slightly shorter than to equaling petals, margins slightly raised, apex acuminate;

petals usually strongly recurved from above base, extending behind plane of sepal bases for more than 1/2 their length, white or rarely pale pink, adaxial veins not conspicuous, oblong-lanceolate, 1.5–2.5 × 0.9–1.5 cm, thin-textured, margins entire, apex acuminate;

stamens ± straight, 6–15 mm, shorter than pistil, slender;

filaments white, ± equaling anthers, slender;

anthers straight, pale lavender-pink or -gray, 2–6.5 mm, dehiscence introrse to latrorse;

ovary prominent, white to pinkish, pyramidal, strongly 6-angled, 3–12 × 3–10 mm, widest above basal attachment;

stigmas erect, recurved, distinct, white, not lobed adaxially, 3–8 mm, widest at base, fleshy, basally thickened, gradually tapered;

pedicel strongly recurved or declined below or angled between bracts, 1.5–3 cm.

erect, rapidly recurving below bracts after pollination, ± odorless;

sepals conspicuous, spreading, green, weakly sulcate, oblong or tapered apically, usually shorter and narrower than petals, 10–23 × 4–8 mm, margins entire, apex rounded-apiculate;

petals erect-spreading, not recurved or only in distal 1/2, white (rarely pale pink), usually with dark madder-purple flecks, rarely almost entirely covered with madder-purple, color not changing with age, veins inconspicuous, not engraved, ovate-cordate to ± orbicular, tapered bluntly apically above middle, 1.3–2.8 × 1–2.4 cm, ± thin-textured, base rounded, cuneate, margins entire, mostly without undulations, apex ± apiculate-acuminate;

stamens erect, 5–12 mm;

filaments white, ± equaling anthers;

anthers straight, yellow, 3–6 mm, dehiscence ± extrorse;

connectives not extended beyond anther sacs;

ovary creamy white, ovoid, weakly 6-angled but angles in close pairs, giving superficial impression of 3-angled ovary, short, 3–9 × 4 mm, somewhat obscured by anthers broadly attached;

stigmas recurved and appearing ± lobed adaxially, at least in dried specimens, connate basally to distinct and closely grouped, white or cream, 2–4 mm, uniformly thick, fleshy;

pedicel strongly erect at anthesis, strongly recurving and elongating below bracts after pollination, 2.5–11 cm.

Fruits

dark red, with fruity fragrance, ovoid, to 3 cm diam., fleshy, juicy.

greenish white, odorless, globose, 0.9–1.2 × 0.8–1 cm, pulpy, not juicy.

2n

= 10.

= 10.

Trillium cernuum

Trillium rivale

Phenology Flowering spring–summer (Apr–Jul). Flowering spring (early Mar–early Jun); withering in summer.
Habitat Rich, mostly deciduous forest southward, mixed deciduous-coniferous forests, swamps, moist coniferous forests northward Open, grassy hillsides, manzanita shrubbery, pine groves, clearings in sequoia groves, roadside banks, ledges, gravelly talus
Elevation 30–600 m (100–2000 ft) 10–1400 m (0–4600 ft)
Distribution
from FNA
CT; DC; DE; IA; IL; IN; MA; MD; ME; MI; MN; ND; NH; NJ; NY; OH; PA; RI; SD; VA; VT; WI; WV; MB; NB; NF; NS; ON; PE; QC; SK; SPM
[WildflowerSearch map]
[BONAP county map]
from FNA
CA; OR
[WildflowerSearch map]
Discussion

Previous authors commonly recognized var. cernuum and var. macranthum, based primarily upon size differences. Plants attributed to var. cernuum are found from Delaware and eastern Pennsylvania northward to Newfoundland, while those attributed to var. macranthum are found mainly farther inland into the Midwest. Although there is a tendency for the eastern seaboard plants to be somewhat smaller and more delicate, and the midwestern and far northern plants to be more robust, there is much variation, largely dependent on soil nutrients. There are regional size trends, but based on my observations of this species in Newfoundland, Michigan, Wisconsin, and Minnesota, I do not believe that the two varieties can be maintained.

In the Gray Herbarium, there is a collection by Richardson labeled “Mackenzie River,” which has been cited by H. M. Raup (1947) and others. W. J. Hooker ([1829–]1833–1840) reported Trillium cernuum “from Saskatchewan to Mackenzie River.” Raup stated that “it is the only evidence for the occurrence of...Trillium in the entire Mackenzie Basin.” Other writers have simply quoted that statement. In view of the relatively great disjunction from the known Saskatchewan stations and in the absence of any other supporting specimens from that area, I believe that there might be locality error on the Richardson sheet. However, it is not beyond possibility that T. cernuum could occur there. This apparent disjunct station is not mapped here.

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

Trillium rivale is confined to the Klamath and Siskiyou mountains of southwestern Oregon and California. It has a strong affinity for banks along streams and adjacent to trickles in Darlingtonia bogs, mainly on serpentine soils. After flowering, the entire plant may enlarge and become more robust and turgid with very glossy leaves.

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

Source FNA vol. 26. FNA vol. 26, p. 102.
Parent taxa Liliaceae > Trillium > subg. Trillium Liliaceae > Trillium > subg. Trillium
Sibling taxa
T. albidum, T. angustipetalum, T. catesbaei, 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
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. rugelii, T. sessile, T. simile, T. stamineum, T. sulcatum, T. underwoodii, T. undulatum, T. vaseyi, T. viride, T. viridescens
Synonyms T. cernuum var. macranthum
Name authority Linnaeus: Sp. Pl. 1: 339. (1753) S. Watson: Proc. Amer. Acad. Arts 20: 378. (1885)
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