keys to the vascular plants of east texas - Botanical Research ...

744 MELANTHIACEAE/TOXICOSCORDION
Stenanthium densum (Desr.) Zomlefer & Judd, (dense, crowded together), BLACK DEATH-CAMAS,
CROW-POISON, BLACK-SNAKEROOT, PINE BARREN DEATH-CAMAS, COASTAL DEATH-CAMAS, OSCEOLA’S-
PLUME. Subscapose, glabrous perennial to ca. 1.5(–2) m tall, bulbose, the bulbs rarely thickened
(to only ca. 2 cm wide), with smooth coats or the outer bulb coats fibrous; leaves crowded near
base, narrowly linear, to ca. 60 cm long, 2–12 mm wide; inflorescence usually a raceme or a
panicle of racemes, with numerous flowers; bracts 2–5(–12) mm long, sometimes with a reddish
tinge; pedicels 20 mm or less long; tepals 6, all � alike, 3–5 mm long, greenish white to creamy
white, cream, or yellowish, narrowed but not so abruptly as to be claw-like at base; with a usually
obscure yellowish gland near the base; filaments slender their whole length; capsules usually
10–20 mm long. Wet areas, damp pinelands, and bogs; Anderson Co. in a “muck bog” in the
Engeling Wildlife Management Area (BRIT; Bridges & Orzell 1989a; MacRoberts & MacRoberts
1998e; Singhurst et al. 2003b) and Henderson and Tyler (Turner et al. 2003) cos. in the Post Oak
Savannah and Pineywoods; e U.S. from NY s to FL w to TX. Apr–Aug. [Oceanorus leimanthoides
(A. Gray) Small, Tracyanthus angustifolius (Michx.) Small, Zigadenus densus (Desr.) Fernald,
Zigadenus leimanthoides (A. Gray) A. Gray] Zigedanus leimanthoides, here included in S.
densum, has often been segregated as a distinct species based on the paniculate (versus racemose
for S. densum) inflorescence, and the “status of S. leimanthoides merits additional systematic
study” (Zomlefer & Judd 2002). However, following Schwartz (2002), we are tentatively including
S. leimanthoides in S. densus (even though Schwartz treated them in Zigadenus).
According to McDearman (1984), Zomlefer (1997a), and Schwartz (2002), while distinct in
some areas, the two entities intergrade (size, inflorescence morphology, flowering time) in the
Gulf coast area. Plant size, which is determined by age and environment, appears to affect inflorescence
morphology—smaller plants tend to have simple racemes, while larger plants develop
panicles. Further research is needed to determine if recognition at the varietal level is appropriate.
The bulb is reported to be “very poisonous” (Correll & Johnston 1970). While not
officially designated as such (e.g., TOES 1993; Carr 2002d; Poole et al. 2002), given its limited
distribution in the state, we consider this species to be of conservation concern in TX. � �
Stenanthium gramineum (Ker Gawl.) Morong, (grass-like), FEATHER-BELLS, FEATHER-FLEECE.
Erect, glabrous, perennial herb from a slender tunicate bulb; stems 0.3–1.5(–ca. 2) m tall, leafy in
lower portion, the blades reduced upward; basal or near basal leaves also usually present and
best developed; leaves numerous, linear, grass-like, to 70 cm long; inflorescence a panicle, 30–90
cm long; flowers numerous, perfect, and/or some staminate; tepals 6, whitish to greenish yellow,
separate nearly to base, linear or narrowly lanceolate, (4–)5–10 mm long, glandless, persistent;
stamens 6, much shorter than the perianth; ovary superior; capsule 6–15 mm long, erect.
Forests, forest margins; widely scattered in the Pineywoods; e U.S. from PA s to FL w to MI and
TX. Jun–Aug. [S. angustifolium (Pursh) Kunth, S. robustum S. Watson, S. gramineum var.
robustum (S. Watson) Fernald] While some authorities (e.g., Kartesz 1999) recognize varieties in
this species, we are not recognizing infraspecific taxa, following Utech (2002b), who said the
varieties were “indistinct and sympatric.” According to Yatskievych (1999), “Some authors do
not consider this taxon [var. robustum] worthy of formal recognition, and intermediates between
it and the typical phase have been documented.” Likewise, Zomlefer (1997a) indicated
that the varieties sometimes recognized in this species are “probably unworthy of taxonomic
recognition.” m/302
TOXICOSCORDION Rydb.
DEATH-CAMAS, POISON-SEGO, STAR-LILY, ZYGADENE
AA genus of ca. 8–10 species of the midwestern U.S. and w North America (Zomlefer et al. 2001;
Zomlefer & Judd 2002; Zomlefer 2003). The species included here has traditionally been treated
in Zigadenus. However, recent chromosomal, molecular, and morphological studies (Zomlefer et
al. 2001; Zomlefer & Judd 2002; Zomlefer 2003) have necessitated significant changes in generic