1 Leaves 3, whorled at the summit of the stem; flowers 1 per plant, solitary and terminal

1 Leaves many, not whorled at the summit of the stem; flowers many per plant, in spikes, racemes, or panicles.

..2 Leaves 1-2 mm wide, linear, stiff, sclerified

..2 Leaves 3-150 mm wide, linear, obovate, or oblanceolate, not notably stiff.

....3 Main (basal) leaves obovate or oblanceolate, the main secondary veins diverging individually (at angles of < 10°) from the midvein in the lower half of the expanded blade and rejoining at the apex; flowers pink, white or cream.

......4 Flowers white to cream; plants dioecious (individual flowers either male or female)

......4 Flowers pink; plants hermaphroditic (individual flowers bisexual)

....3 Main (basal) leaves linear, elliptic, or obovate, the main veins parallel, all diverging at the base of the leaf and rejoining at the apex; flowers white, cream, yellowish, greenish, or brownish.

........5 Inflorescence a spike or raceme.

..........6 Inflorescence a spike (the flowers sessile); [of s. GA south to s. FL, and e., se., and c. TX westwards]

..........6 Inflorescence a raceme (the flowers pedicellate); [collectively widespread in our area].

............ 7 Basal leaves 4-many, (4-) 7-10 (-23) mm wide; basal leaves not enclosed by a basal sheath (all basal leaves with blades, and the leaf bases usually white); capsule suborbicular, 5-7 mm long, 5-7 mm wide; older flowers and developing capsules turning green; bulb broadly ovoid; [widespread in our area, including Coastal Plain pine savannas]

........5 Inflorescence a panicle.

............ ..8 Inflorescence axes scurfy-pubescent; seeds winged; leaves either linear or broader, < 14 cm wide.

............ ....9 Leaves basally disposed; leaves not at all to slightly plicate, 1-14 cm wide; tepals glabrous, 4-9 mm long, 1-3 mm wide (3-5 mm wide in M. hybridum), with either conspicuous (M. hybridum) or diffuse (M. parviflorum and M. woodii) glands; filaments fused to the basal claw of the tepal

............ ....9 Leaves cauline; leaves strongly plicate, 6-15 cm wide; tepals pubescent, 8-13 mm long, 3-5 mm wide, with a conspicuous pair of glands near the base of the tepal blade (these sometimes more or less fused); filaments free from the tepals

............ ..8 Inflorescence axes glabrous; seeds not winged (though sometimes angled); leaves linear, < 2 cm wide.

............ ......10 Leaves strongly keeled, (5-) 10-20 mm wide; plant colonial, from thick, hard, horizontal, short-creeping rhizomes covered with fibrous old leaf bases; inner tepals (petals) 7-17 mm long, distinctly clawed, acute-acuminate at the tip, bearing 2 glands well above the base

............ ......10 Leaves slightly or not at all keeled, 2-12 mm wide; plant solitary, from a bulbous or semibulbous base; inner tepals (petals) 3-6 or 7-12 mm long, clawed or not, bearing either a single (sometimes obscure to essentially invisible) gland near the base or a bilobed gland well above the base.

............ ........11 Inner tepals 3-10 mm long, not clawed, with a single, unlobed gland borne near the base (this often difficult or impossible to see, consisting only of a greenish line at the very base of the tepal); [of acid habitats of the Mountains, Piedmont, and Coastal Plain]

............ ........11 Inner tepals (petals) 6-12 mm long, clawed, with a single unlobed or bilobed gland borne well above the base; [of calcareous habitats].

............ ..........12 Tepals 6-8 mm long, the gland unlobed; [nw. MS, s. MO, AR, and LA westwards]

............ ..........12 Tepals 7-12 mm long, the gland bilobed; [calcareous Appalachians of PA, VA, WV, and NC; s. OH; s. MO; and northwards]

1 Tepals lanceolate, the tip acute-acuminate.

..2 Inflorescence a diffuse panicle up to 3 dm wide, the terminal racemose portion reduced or absent; flowers on mid-portion of lateral branches with pedicels 1.6-4 mm long, spaced 8-15 mm apart; uppermost non-bracteal stem leaf 4-14 cm above ground level; flowering mid Sep-mid Oct; [of sandstone rockhouses of the Cumberland Plateau]

..2 Inflorescence branched but not diffuse, typically up to 1.5 dm wide, the terminal racemose portion present and up to 3 dm long; flowers on mid-portion of lateral branches with pedicels 0.3-1.1 mm long, generally spaced 3-7 mm apart; uppermost non-bracteal stem leaf 22-66 cm above ground level; flowering May-late Aug; [of various wet to dry habitats, widespread in our area]

....3 Stem 4-10 mm in diameter; plants 3-18 dm tall; tepals 3-8 (-10) mm long; capsules 6-9 mm long; seeds 5-6 mm long; [of dry to mesic slopes and outcrops]

....3 Stem 7-15 mm in diameter; plants 12-20 dm tall; tepals 5-10 mm long; capsules 9-10 mm long; seeds 5-8 mm long; [of sphagnous bogs and swamps]

1 Tepals obovate, the tip rounded-obtuse.

......4 Basal sheaths purple, fibers absent (occasionally sparse, rarely moderate); inflorescence unbranched (a raceme) or branched (a panicle); number of pedicels per 5 cm of inflorescence axis 30-60 (mean 43); tepals fade to pink or purple on living plants; [southern Atlantic and Gulf Coastal Plain].

........5 Largest leaves on a plant 4-12 mm wide (mean 7.1); inflorescence branched (a panicle) (rarely simple); capsules averaging 13.3 mm long; [GA and FL Panhandle west to e. TX]

......4 Basal sheaths brown (occasionally purple tinged), densely to moderately clothed with remnant fibers; inflorescence branched (a panicle); number of pedicels per 5 cm of raceme 22-50 (mean 32); tepals fade to dull green or olive on living plants; [Eastern Highland Rim of TN, Southern Appalachians, and Coastal Plain of NY-NJ-DE-MD].

..........6 Pedicel bracts 3-6.5 mm (mean 4.5) long; largest leaves 3-11 mm wide (mean 7.7); [Southern Appalachian Mountains and northern Atlantic Coastal Plain]

..........6 Pedicel bracts 2.5-5.5 mm (mean 3.3) long; largest leaves 2.5-7 mm wide (mean 4.8); [Eastern Highland Rim of s. TN and n. AL]