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1 Plants prostrate, with scapes very short, holding bracts (leaves) near the ground; floral fragrance of rotting meat or manure-scented |
2 Anther dehiscence extrorse; bract apices rounded or obtuse, typically mottled only in 2 colors, silver and green |
2 Anther dehiscence introrse; bract apices obtuse or acute, conspicuously mottled in silver and three or more shades of green |
3 Rhizome 0.3-1 cm in diameter, branching, forming clonal patches; scape straight, ascending, densely puberulent on angles; bract blades typically < 6 cm long; petals 1.5-3 cm in length, widest at middle; floral fragrance of horse manure |
3 Rhizome 0.8-1.5 cm in diameter, unbranched, not forming clonal patches; scape S-shaped, decumbent or semi- decumbent, glabrous; bract blades typically > 7 cm long; petals (2.2-) 3.0-5.0 (-6.0) cm in length, widest above the middle; floral fragrance of rotten meat |
1 Plants erect or ascending, with tall scapes holding bracts (leaves) well above ground, or sometimes bract tips barely touching the ground in early anthesis; floral fragrance various, foetid, pleasant, or mildly unpleasant |
4 Sepals abruptly deflexed between and below the leaves, distinctly descending below the approximately horizontal plane of the leaves; filaments about as long as incurved anthers; [ T. recurvatum group]. |
5 Anther connectives slightly incurved or erect; filaments short (< ½ the anther length); [variously endemic to either Kershaw and Richland counties in the inner Coastal Plain of SC ( Trillium oostingii) or Hamblen and Hawkins counties in the Ridge and Valley of TN ( Trillium tennesseense)]. |
6 Ovary 6-16 mm long; filaments less than ½ as long as the ovary; stigma lobes ca. 1× as long as the ovary, the stigmatic surfaces smooth; [ endemic to Kershaw and Richland counties in the inner Coastal Plain of SC] |
6 Ovary 2-4 mm long; filaments about equal to the ovary; stigma lobes ca. 2× as long as the ovary, the stigmatic surfaces strongly crested- undulate; [ endemic to Hamblen and Hawkins counties in the Ridge and Valley of TN] |
5 Anther connectives strongly incurved; filaments long, > ½ the anther length; [primarily west of the Blue Ridge and south into the Gulf Coastal Plain, very rarely disjunct to the Mountains or upper Piedmont]. |
7 Leaves sessile or subsessile, borne in a descending or drooping manner (similar to the sepals); petals usually 4-7× as long as wide, strongly clawed |
7 Leaves distinctly petiolate, borne in an ascending manner (strongly contrasting in position with the strongly deflexed sepals); petals usually ca. 2× as long as wide, attenuate to weakly clawed |
4 Sepals erect, ascending, or spreading, usually borne at or above the approximately horizontal plane of the leaves; filaments much shorter than the upright anthers. |
8 Petals spreading to horizontal, with 1-2 spiral twists (looking something like an airplane propeller); anther dehiscence extrorse (toward the outside of the flower); [ T. sessile group] |
8 Petals erect to slightly spreading, not spirally twisted; anther dehiscence introrse (toward the inside of the flower), or latrorse (toward the side). |
9 Petals broadly spatulate, clawed, broadly rounded (though sometimes with an apiculus) at the tip; petals pale lemon-yellow (the claws greenish or maroon); flower fragrance clove-like; [of the Savannah River drainage, from sw. NC southeastward along the GA-SC border]; [ T. sessile group] |
9 Petals lanceolate, elliptic, obovate, or oblanceolate, but not broadly spatulate and distinctly clawed, generally acute at the tip; petals maroon-red, purplish-brown, yellow, or green; flower fragrance various; [collectively widespread in our area]. |
10 Stigmas > 1.5× as long as the ovary; stamens about 0.5× as long as the petals; anther connectives prominently prolonged into a beak 1.0-5.0 mm long (beyond the anther sacs); [ T. sessile group] |
10 Stigmas as long as the ovary or shorter; stamens < 0.5× as long as the petals; anthers blunt, the connectives extended < 1.0 mm beyond the anther sacs. |
11 Ovary ellipsoid; leaves acute, the margins of the outer 1/3 more or less straight; leaf blade mottled with 3 or more shades of green, the palest shade forming a very conspicuous pale silvery-green streak along the midvein; [of the Coastal Plain and fall-line area of GA, AL, and FL Panhandle]; [ T. sessile group]. |
12 Stem 2.5-3× as long as the leaves; petals oblanceolate- obovate, usually 1.5-3× as long as wide; flower fragrance yeasty-sweet (or similar to overripe bananas) |
12 Stem 1-2× as long as the leaves (though sometimes elongating late in the season); petals narrowly elliptic to oblanceolate- obovate, usually 3-5× as long as wide; flower fragrance yeasty-sweet (or reminiscent of stale beer) |
11 Ovary ovoid; leaves acute to acuminate, the margins of the outer 1/3 convex; leaf blade mottled with 2-3 shades of green, paler shades sometimes prominent along the midvein, but not as above; [collectively widespread in our area]; [ T. maculatum group]. |
13 Petals < 4× as long as wide, elliptic- oblanceolate to oblanceolate; [of inland provinces, rarely in the Coastal Plain]. |
14 Flower fragrance fruity-spicy, like green apples or Calycanthus (rarely musky); petals maroon, bronze, green, yellow; portions of ovary and stamens purplish during anthesis |
14 Flower fragrance lemon-like; petals greenish-yellow darkening to yellow; ovary and stamens greenish-white during anthesis |
13 Petals > 4.5× as long as wide, narrowly oblanceolate- spatulate to linear- oblanceolate; [of the Coastal Plain, rarely farther inland]. |
15 [of TX, OK, AR, MO, KS, and IL] |
16 Leaf apices blunt to rounded; leaf upper surface with numerous stomates across the surface (visible as white dots with 10× magnification); stamens ca. 1.5× as long as the ovary |
16 Leaf apices acute; leaf upper surface lacking stomates (or present only near apex); stamens ca. 2× as long as the ovary |
15 [of TX, LA, MS, AL, GA, SC, and FL] |
17 Ovary 3-angled at base of stigmas (rarely 6-angled); petals 7-17 mm wide, narrowly spatulate (appearing clawed); outer whorl of stamens broader, anther dehiscence introrse; flower fragrance faintly spicy-fragrant, banana-like; [of AL, n. FL, GA, and e. SC] |
17 Ovary 6-angled; petals 3-8 mm wide, linear- oblanceolate, narrowly elliptic, to linear- lanceolate (weakly or not clawed); flower fragrance putrid, like rotting meat; [of MS, LA, and e. TX]. |
18 Stamens ca. 2× as tall as the ovary; [of w. LA and e. TX] |
18 Stamens <1.5× as tall as the ovary; [of c. and e. LA and w. MS]. |
19 Petals 3-5 mm wide; anther dehiscence introrse; anther connective extending 1-1.5 mm beyond the anther sacs |
19 Petals 4-8 mm wide; anther dehiscence latrorse; anther connective scarcely extending beyond the anther sacs |
1 Flowers held below the leaves (the pedicel declined below a horizontal plane). |
2 Stamens far exceeding the pistil, filaments as long as the ovary or longer, at least partly maroon, the anther sacs yellow to maroon; ovary small, globose, 3-12 mm long, dark purplish black; flower fragrance pungent, rose-like; pedicel long, 3-13 cm long; petals strongly overlapping, usually maroon (rarely white or whitish) |
2 Stamens at most 1.5× longer than the pistil, filaments shorter than the ovary, white (less commonly purplish), the anther sacs lavender to vivid purple (or albino); ovary white to pink or dull red, large, ovoid, 10-17 mm long; flower fragrance various; pedicel short to long, 1.5-12 cm long; petals not strongly overlapping, usually white (rarely maroon). |
3 Pedicels short, 1.5-4 cm long. |
4 Anthers 7.5 mm long or less, about as long as the filaments or shorter; petals narrowly elliptic to obovate, often scarcely larger than the sepals, delicate, occasionally margined in pink or green; [of damp forests of n. VA and northward] |
4 Anthers 7.0 mm long or more, longer than the filaments; petals ovate to elliptic, much broader than the sepals; [of mesic forests of n. NC southward] |
3 Pedicels long, 4-12 cm long. |
5 Stamens about as long as the ovary or slightly longer; filaments short, ca. 1/3 the length of the anthers or shorter; filaments ½ as long as the ovary or shorter; pollen creamy to pale yellow; filaments and anthers white, the anthers at least in part somewhat appressed against the ovary |
5 Stamens far exceeding ovary height; filaments ca. ½ the length of the anthers; pollen creamy, yellow, or pale grayish purple; anthers and filaments also variable in color, mostly white, occasionally purplish; anthers mostly longer than the ovary and not appressed against it |
1 Flowers held at or above the level of the leaves (the pedicel nearly horizontal, inclined above the horizontal, or erect). |
6 Ovary flask-shaped, broadest near the base, usually white to pinkish (sometimes darker); petals usually white to creamy white (maroon forma occasional). |
7 Stamens about as long as the ovary or slightly longer; filaments short, ca. 1/3 the length of the anthers or shorter; filaments ½ as long as the ovary or shorter; pollen creamy to pale yellow; filaments and anthers white, the anthers at least in part somewhat appressed against the ovary |
7 Stamens far exceeding ovary height; filaments ca. ½ the length of the anthers; pollen creamy, yellow, or pale grayish purple; anthers and filaments also variable in color, mostly white, occasionally purplish; anthers mostly longer than the ovary and not appressed against it |
6 Ovary globose, widest near the middle, black to purplish black; petals white, maroon, yellowish, or otherwise. |
8 Petals lanceolate to narrowly ovate or elliptic, spreading from base in the same plane as the sepals, rarely > 2× as broad as the sepals; sepals 0.5-0.8× as long as the pedicel, weakly sulcate-tipped (roundly keeled and upturned near apex); flower fragrance unpleasant, musty. |
8 Petals ovate, overlapping in some instances and forming a cup-shaped base, variably recurved apically, > 2× as broad as the sepals; sepals 0.2-0.7× as long as the pedicel, sulcate-tipped; fragrance pleasant, sweet to fungal. |
9 Sepals 0.4-0.7× as long as the pedicel; leaves broadly elliptic; stamens 1.2-1.8× pistil height; flowers generally large, petals much longer than the sepals; sepals green; petals usually white (rarely maroon); flower fragrance sweet, like green apples |
9 Sepals 0.2-0.4× as long as the pedicel; leaves broadly obovate; stamens 0.9-1.6× pistil height; flowers relatively small, petals only slightly longer than the sepals; sepals suffused with purple; petals usually maroon (rarely white); flower fragrance fungal, like fresh mushrooms |
1 Petals white with triangular red blaze (rarely entirely white or pinkish); anther sacs lavender to white, dehiscence extrorse; fruit a red berry; leaves long- acuminate; [of acidic sites in the Mountains, generally strongly associated with either Pinus, Tsuga, Picea, Rhododendron, or other heaths]; [genus Trillidium] |
1 Petals white to deep pink, lacking a red blaze; anther sacs yellow, dehiscence introrse; fruit a white to greenish-white, fleshy, irregularly dehiscent capsule; leaves obtuse to acute (or somewhat acuminate in T. grandiflorum); [of less distinctly acidic sites, collectively widespread in our area]. |
2 Pedicel declined below the leaves (rarely erect); sepals arcuate- recurved; anthers irregularly twisted outward; pollen egg-yolk yellow; [subgenus Delostylis] |
2 Pedicel inclined above leaves to strictly erect; sepals not arcuate- recurved; anthers erect, regular; pollen light yellow (richer yellow in T. grandiflorum). |
3 Sepals narrower than the petals, acute; anthers white to greenish-white between the anther sacs; leaves obtuse, acute, or acuminate; pedicel somewhat angled from the vertical. |
4 Ovary obscurely 3- lobed; leaves < 5 cm long, blue-green, obtuse; [subgenus Callipetalon] |
4 Ovary sharply 6-angled (- winged); leaves > 5 cm long, green, acute to acuminate. |
5 Petals obovate, tightly rolled at base, abruptly flared near the apex; leaves broadly elliptic, acuminate; style minute, < 1.0 mm long; [subgenus Callipetalon] |
5 Petals elliptic, loose, gradually separating; leaves ovate, acute; style conspicuous, > 1.5 mm long; [subgenus Delostylis] |
3 Sepals about as broad as the petals or broader, obtuse; leaves obtuse; anthers purplish-green between anther sacs; pedicel erect through fruiting; [ Trillium pusillum complex of subgenus Delostylis]. |
6 Leaves with stomates on the upper surface, appearing farinose; [of n. GA] |
7 Leaves linear, > 4× as long as wide; [of n. GA] |
7 Leaves ovate or elliptic, not linear, < 4× as long as wide; [of sw. AR, nw. LA and e. TX] |
6 Leaves without stomates on the upper surface, appearing glabrous. |
8 Pedicels < 10 (-12) mm long. |
9 Pedicels (0-) 0.5-1.0 mm long; leaves (1.5-) 2.0-2.4 (-2.9)× as long as broad; leaves (14-) 15-20 (-22.5) mm wide; filaments (4.5-) 4.6-5.8 (-8) mm long; [of upland forests of Mountains of w. VA and e. WV] |
9 Pedicels (0.5-) 1.0-6.6 (-11) mm long; leaves (2.1-) 2.5-3.8 (-6)× as long as broad; leaves (6-) 10-17 (-25) mm wide; filaments (2.5-) 3-5 (-6.5) mm long; [of wetland forests]. |
10 Anthers (3.2-) 4.5-6 (-7) mm long; stamens (5.7-) 8.4-10.9 (-12.5) mm long; stigmas (1-) 2.1-3 (-5) mm long; leaves elliptic; [of the outer Coastal Plain of e. MD, e. VA, and ne. NC] |
10 Anthers (2.5-) 2.7-4.8 (-6.8) mm long; stamens (5.7-) 6-9.2 (-13.2) mm long; stigmas (1-) 1.2-2.5 (-4.7) mm long; leaves ovate; [of the upper Coastal Plain and Piedmont of ne. NC, se. VA, and Mountains of sw. VA]. |
11 Pedicels (0.5-) 1-2.1 (-7) mm long; stamens (6-) 7.5-9.2 (-11) mm long; stigmas (1-) 2-2.5 (-4.7) mm long; [of upper Coastal Plain of e.VA] |
11 Pedicels (1.2-) 1.8-6.6 (-11) mm long; stamens (5.7-) 6-7.6 (-13.2) mm long; stigmas (1-) 1.2-2 (-2.5) mm long; [of Piedmont to edge of upper Coastal Plain of ne. NC] |
8 Pedicels 10-56 mm long. |
12 Leaves ascending; sepals ca. 1.4× as long as the petals; [of sphagnum bogs in the s. SC sandhills] |
12 Leaves horizontal to declining; sepals 0.9-1.1× as long as the petals. |
13 Leaves narrower, (1.9-) 3-4.1 (-5.6)× as long as wide; pedicels (23-) 25-33 (-56) mm long; [of calcareous savannas and swamps] |
13 Leaves broader, (2-) 2.7-3.4 (-5.5)× as long as wide; pedicels (7-) 13-30 (-45) mm long. |
14 Leaves ovate, acute; sepals (14-) 22-30 (-41) long, (4-) 6-11 (-17) mm wide, (2-) 3-4.3 (-5.6)× as long as wide; [generally of upland rocky slopes] |
14 Leaves elliptic, rounded; sepals (13-) 18-25 (-30) long, (4-) 6-8 (-12) mm wide, (1.8-) 2.7-3.1 (-4)× as long as wide; [generally of swamps and floodplains] |
