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longbract wakerobin, Underwood's trillium

bent trillium, declined trillium, drooping trillium, nodding wakerobin

Rhizomes

horizontal, brownish, short, thick, praemorse, not brittle.

somewhat erect, thick, praemorse.

Scapes

1–2, round in cross section, 0.8-2 dm, slender to stout, glabrous.

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

Bracts

usually drooping, often touching ground in early anthesis, sessile;

blade pale silvery green, strongly mottled in 3 or more shades of dark green and bronze, sometimes maroon, mottling becoming obscure with age, ovate-lanceolate to obovate, 6.5–12 × 5–7.8 cm, margins of distal 1/3 straight from rounded base to apex, apex acuminate.

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 fetid, especially when first open;

sepals displayed above bracts, spreading, green or purple on adaxial surface, lanceolate, 4.5–5 × 8–12 mm, margins entire, flat, apex rounded-acute;

petals long-lasting, erect-spreading, ± connivent, ± concealing stamens and ovary or at least partially obscuring stamens, tips ± incurved, dark maroon-red, or purplish red, brownish maroon, or yellowish green, not spirally twisted, oblanceolate to elliptic, 3–5.5+ × 1–1.5 cm, usually 3–4 times longer than wide, thick-textured, margins entire, apex acute;

stamens ± erect to weakly incurved, 14–17 mm;

filaments purple, 1–2 mm;

anthers 8–15 mm, thick, dehiscence latrorse;

connectives brown-purple, straight, extended 1–2 mm beyond anther sacs, apex somewhat acute;

ovary purple, ellipsoid, 6-angled, 6.3–11 mm;

stigmas erect, abruptly recurved upon ovary, distinct, purplish, linear, 1.5–5 mm, slightly thickened basally, 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

baccate, purple-black to dull greenish maroon, odorless, ovoid to obovoid, 6-angled (-ridged), 0.7–1 cm diam., 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.

Trillium underwoodii

Trillium flexipes

Phenology Flowering mid winter–spring (late Feb–mid Apr). Flowering spring (Apr–early Jun).
Habitat Rich to dryish deciduous forests of mature or second-growth timber, dominated by oaks or with beech-oaks, occasionally with scattered pines present, flat ground along streams where soil can be fairly moist, rich clay or sand 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
AL; FL; GA
[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 underwoodii can cause considerable confusion for the beginning student of the genus. In some ways it closely resembles a small-statured T. cuneatum. As T. underwoodii continues to expand after flowering, it may become somewhat taller and less “ground hugging,” and it then appears similar to a smaller plant of T. decipiens, which grows in parts of the same range, especially when its bracts do not touch the ground at anthesis. It also has vague similarities to T. reliquum, with which it grows sympatrically in parts of its range. Care should be taken to observe the details of floral structure accurately.

Distribution of Trillium underwoodii is much more restricted than that given by J. K. Small (1933), who indicated a range extending from Alabama to North Carolina and Arkansas.

(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. 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. 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 Small: Bull. Torrey Bot. Club 24: 172. (1897) Rafinesque: Autik. Bot., 133. (1840)
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