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 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]

             7 Basal leaves 1-3, 2-6 (-10) mm wide; basal leaves enclosed by a basal purple (bladeless) sheath 3-8 cm long; capsule conical, 7-12 mm long, 3-4 mm wide; older flowers and developing capsules turning pink; bulb cylindrical; [of Coastal Plain pine savannas and similar habitats]

        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]