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

894 POACEAE/DICHANTHELIUM
Dichanthelium clandestinum (L.) Gould, (hidden), DEER-TONGUE, DEER-TONGUE ROSETTE GRASS.
Plant 40–80(–140) cm tall; leaf blades usually (12–)15–30 mm wide; leaf sheaths, at least lower
ones, papillose-hispid with spreading hairs; spikelets (2.3–)2.7–3.5(–4) mm long. Sandy woods;
Bowie (BRIT) and Polk (Turner et al. 2003) cos., also collected at Dallas by Reverchon in 1875,
not found there since (Mahler 1988), also reported for n portions of Pineywoods and Post Oak
Savannah (Gould 1975b); se Canada and e U.S. w to IA and TX. Apr–Jun, again late summer–fall.
[Panicum clandestinum L.] The stiff hairs of the leaf sheath are reported to be irritating to the
skin (Gould & Clark 1978); L. Brown (pers. comm.) notes that this feature is lost on herbarium
material. This species is similar to D. latifolium (Gould & Clark 1978), but it can be distinguished
by its papillose-hispid leaf sheaths (versus glabrous or softly villous in D. latifolium).
Hybrids with D. dichotomum, D. scabriusculum, and possibly D. scoparium are known
(Freckmann & Lelong 2003a). 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. �
Dichanthelium commutatum (Schult.) Gould (variable, changing), VARIABLE ROSETTE GRASS.
Culms (15–)40–75 cm tall; leaf sheaths glabrous or pubescent on the margins; larger leaf blades
cordate-clasping at base, usually � 10 cm long, occasionally to 15 cm, 8–25 mm wide; spikelets
usually 2.4–3.2 mm long, sometimes purplish. Moist areas or deep shade, sandy soils; widespread
in East TX; also n Gulf Prairies and Marshes; widespread in the e U.S. w to MI and TX.
Apr–Jun, again late summer–fall. [D. commutatum subsp. ashei (G. Pearson ex Ashe)
Freckmann & Lelong, D. commutatum subsp. equilaterale (Scribn.) Freckmann & Lelong, D.
commutatum subsp. joorii (Vasey) Freckmann & Lelong, Panicum commutatum Schult., Panicum
divergens Kunth] Some authorities (e.g., Freckmann & Lelong 2003a) recognize infraspecific
taxa in this species; they are reported to intergrade where they occur together.
Dichanthelium consanguineum (Kunth) Gould & C.A. Clark, (related, close of kin), BLOOD RO-
SETTE GRASS, KUNTH’S PANIC GRASS. Culms 10–60 cm tall, the nodes bearded, the internodes villous;
ligule absent or less than 1 mm long; leaf blades 4–8 mm wide; spikelets 2.4–3 mm long,
densely pubescent, ± attenuate basally. Sandy soils, open woods; Angelina, Bastrop, Freestone,
Hardin, Liberty, Nacogdoches, Newton (BRIT), Austin, Gonzales, Henderson, Leon, Montgomery,
Polk, Robertson (TAES—annotated by S. Hatch), Harris, Jasper, and Jefferson (Turner et al.
2003) cos.; also n Gulf Prairies and Marshes; e U.S. from VA s to FL w to OK and TX. Apr–Jun,
also summer–fall. [Panicum consanguineum Kunth] This species was treated as D. acuminatum
var. consanguineum by Wipff and Jones (1994 [1995]) and Hatch (2002), and it indeed is similar
to that species. However, its ligules are consistently shorter and its spikelets are typically larger
than those of D. acuminatum. We are therefore following Gould and Clark (1978), Freckmann
(1981a), Allen (1992b), and Freckmann and Lelong (2003a) in treating D. consanguineum as a
separate species. According to Gould and Clark (1978), D. consanguineum is also similar to D.
ovale Elliott, and Freckmann and Lelong (2003a) have suggested that hybridization occurs between
D. consanguineum and both D. aciculare and D. ovale.
Dichanthelium depauperatum (Muhl.) Gould, (impoverished), STARVED ROSETTE GRASS, STARVED
PANIC GRASS. Similar to D. linearifolium and intergrading with it; plant 20–60 cm tall; culms not
branching above base; leaves mostly basal, pilose to hispid or nearly glabrous, the sheaths commonly
thinly pilose, the blades often glabrous on upper surface; blades of basal and culm leaves
all 15–40 times as long as wide, 1–5 mm wide; spikelets usually 3–4.8 mm long; upper (fertile)
floret shorter than the ± beaked upper glume and lemma of lower floret. Woods, grassy areas,
roadsides, particularly on sandy soils; widely scattered in East TX; se Canada and widespread
in the e U.S. w to CO and TX. Apr–May, also summer. [Panicum depauperatum Muhl.] Hybridization
with D. linearifolium is known (Freckmann & Lelong 2003a).
Dichanthelium dichotomum (L.) Gould, (2-forked or -parted), FORKED PANIC GRASS, CYPRESS RO-
SETTE GRASS. Plant usually (20–)40–80(–100) cm tall, often becoming much-branched with age,