Herbs, perennial, from short, thick, vertical rhizomes and swollen basal bulbs; roots contractile, fleshy. Stems erect, simple, hollow, robust, basally thickened, leafy. Leaves alternate, simple, strongly veined, narrowly to broadly orbicular, often plicate, reduced upwards, narrowed into closed, tubular, often overlapping sheaths. Inflorescences compound-racemose or large terminal-paniculate, bracteate, pubescent. Flowers bisexual or some proximal ones staminate; perianth perigynous, rotate to ± campanulate, with hypanthium fused to base of ovary; tepals persistent, 6, spreading to erect, distinct to weakly connate basally, off-white, green, yellow, or purple, petaloid, not clawed, equal to subequal, margins entire or erose-fimbriate; glands 1-2, basal, on adaxial surface, V-shaped over midrib or marginal pair; stamens 6, perigynous; filaments distinct, filiform; anthers persistent, 1-locular with confluent thecae, cordate-reniform, dehiscence apical/valvate; ovary superior or partly inferior, 3-locular; styles 3, erect to divergent, distinct, short; stigmas elongate, extending down inner style surfaces. Fruits capsular, deeply 3-lobed, style beaks persistent, dehiscence septicidal. Seeds ellipsoid to fusiform, flat, broadly winged (± globose with wings reduced to basal ridges in V. fimbriatum). x = 8. The number of Veratrum species depends on the taxonomic treatment of four wide-ranging species complexes, three of which are entirely or mainly Eurasian (V. album, V. nigrum Linnaeus, and V. maackii Regel) and one North American (V. viride) (O. Loesener 1926, 1927, 1928; B. Mathew 1989; J. H. Zimmerman 1958). The Asian species have been variously circumscribed (Chen S. C. and H. Takahashi 2000; H. Kato et al. 1996; T. Nakai 1937, 1937b; N. S. Lee 1985, 1985b). Generic size further depends on inclusion or not of the closely related Melanthium (J. D. Ambrose 1975, 1980; P. Goldblatt 1995; M. N. Tamura 1998; W. B. Zomlefer 1997b), here treated as a separate genus. The medicinal/poisonous properties of Veratrum involve a complex of cerveratrum and jerveratrum alkaloids, some with proven hypotensive properties and others that are highly toxic to humans and livestock (S. M. Kupchan et al. 1961; A. Osol et al. 1960; I. W. Southon and J. Buckingham 1989). Veraloid, a standard mixture of the most hypotensive Veratrum alkaloids, was widely prescribed until late in the nineteenth century, when emetic side effects greatly curtailed its use. The types and concentrations of alkaloids vary with the species, plant part, and season (C. A. Taylor 1956, 1956b). Several Veratrum species are occasionally cultivated surrounded by low-growing plants for their architectural appeal in mesic or bog gardens. Century-old plants grow from the long-lived rhizome-bulb.
Herbs, perennial, subscapose, from erect, tunicate bulbs with short, vertical rhizomes; fibrils persistent, brown, stiff; roots contractile, fleshy. Stems erect, simple, leafy, hollow, basally thickened. Leaves basal, simple, reduced upwards, bases sheathing; blade linear, oblanceolate, elliptic to obovate, rarely plicate, glabrous, basally canaliculate, apex tapered to acute; sheaths tubular, closed. Inflorescences terminal, compound-racemose to open-paniculate, flexible, axes floccose; bracts clasping, linear to subulate. Flowers of distal racemes bisexual, progressively smaller distally, proximal flowers staminate; tepals persistent, 6, spreading, distinct to weakly connate basally, slightly adnate to ovary base, petaloid, gradually to abruptly narrowed into claws or claws absent, subequal, margin entire or undulate, apex acute to obtuse; perigonal nectaries obscure to very prominent, 2 per tepal, adaxially basal on either side of midvein; stamens 6, adnate to tepal bases; filaments strongly incurving; anthers basifixed, 1-locular, cordate-reniform; pollen sacs fugacious, confluent, dehiscence apical/valvate; ovary superior to partly inferior, nearly distinct, 3-locular; sepal nectaries absent; styles persistent, 3, spreading to recurved, turning inwards with age, distinct; stigmas minute; pedicel pubescent. Fruits capsular, deeply 3-lobed, dehiscence septicidal, then adaxially loculicidal; styles persistent, 3, beaklike. Seeds pale yellow to tan, broadly winged, flat, elliptic to lanceolate. x = 8. Melanthium, often wholly or partly included in the closely related Veratrum (J. D. Ambrose 1975, 1980; S. M. Kupchan et al. 1961; J. H. Zimmerman 1958; W. B. Zomlefer 1997b; W. B. Zomlefer et al. 2001), is treated here as distinct (N. L. Bodkin 1978; B. Mathew 1989; M. N. Tamura 1998; S. Fuse and M. N. Tamura 2000). The eastern North American species of Melanthium differ from Veratrum primarily in their open inflorescences, which appear delicate and flexible; glabrous leaves; clawed tepals with two distinct, nonmarginal glands on either side of the midrib; and incurving, fugacious stamens adnate to the tepals (N. L. Bodkin 1978). Resolution of the problematical Melanthium-Veratrum species series will require full molecular and phylogenetic analysis of the group, especially of the narrow-leaved Asian Veratrum, several of which approximate Melanthium, such as V. mengtzeanum Loesener, V. micranthum Wang & Tang, V. stenophyllum Diels, and V. taliense Loesener f. (B. Mathew 1989). In eastern North America, an ecological replacement gradient occurs within the genus. Melanthium virginicum occurs mostly in wet habitats at lower elevations, while the Appalachian M. latifolium and the Ozark M. woodii commonly grow on mesic slopes, and M. parviflorum is most frequently found on or near mountain crests. Species of Melanthium should be considered poisonous, since complex alkaloids derived from steroidal precursors, similar to those in Veratrum, are present (S. M. Kupchan et al. 1961; R. Hegnauer 1962+, vol. 2; R. M. T. Dahlgren et al. 1985).
Fls polygamous; tep 6, free from the ovary, narrowed at base, not glandular; stamens 6; filaments slender, free or adnate to the perianth at the very base; anthers extrorse, obcordate, with confluent thecae; ovary superior, 3-lobed, each lobe terminated by a short style; capsule ovoid, septicidal, subtended by the withered perianth; seeds large, flat, the small embryo surrounded by a broad wing; tall, coarse, poisonous herbs, perennial from a stout rhizome, with large broad lvs and a terminal panicle of green or purple fls. 30, N. Hemisphere.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.
Fls polygamous; tep 6, spreading, clawed at base, bearing a pair of glands at the base of the blade; filaments adnate to the claws; anthers extrorse, obcordate, with confluent thecae; ovary superior, 3-lobed, each lobe terminated by a short style; capsule ovoid, septicidal, subtended by the withered perianth; seeds several, elliptic, thick about the center, bordered by a firm wing; poisonous perennial herbs from stout rhizomes, with elongate sheathing lvs and a larger, terminal, pubescent panicle of green or greenish fls. 5, N. Amer.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.