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

906 POACEAE/DICHANTHELIUM
varietal level. While treating them as subspecies, Freckmann and Lelong (2003a) noted that the
taxa “are mostly sympatric and sometimes grow together, with occasional intergradation.” According
to Freckmann and Lelong (2003a), “The primary panicles are briefly open-pollinated
in April or May; the secondary panicles, which are produced from May through November, are
cleistogamous.”
1. Spikelets 1.6–2.1 mm long, pubescent; lower glume ca. 1/2 length of spikelet; leaf blades usually
glabrous _________________________________________________________________ var. leucoblepharis
1. Spikelets 1.1–1.6 mm long, glabrous; lower glume ca. 1/3 as long as spikelet; leaf blades pilose
_____________________________________________________________________________ var. strigosum
var. leucoblepharis (Trin.) Freckmann, (white-fringed, as with eyelashes). Culms usually 30 cm
or less tall. Upshur (BRIT), Angelina, and Robertson (Turner et al. 2003, as D. leucoblepharis)
cos., also cited for e TX by Freckmann and Lelong (2003a), and for TX by Gould and Clark
(1978); se U.S. from NC s to FL w to TX. [D. leucoblepharis (Trin.) Gould & C.A. Clark, D.
strigosum (Muhl.) Freckmann subsp. leucoblepharis (Trin.) Freckmann & Lelong, Panicum
ciliatum Elliott, Panicum leucoblepharis Trin., Panicum strigosum Muhl. var. leucoblepharis
(Trin.) Lelong, Panicum strigosum var. puberula C.F. Reed] The complicated nomenclatural history
of this taxon was discussed by Veldkamp (1976) and Hansen and Wunderlin (1988). Turner
et al. (2003) recognized this variety as a distinct species, D. leucoblepharis, while Freckmann
and Lelong (2003) treated it as a subspecies of D. strigosum. 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 variety to be of conservation concern in TX. �
var. strigosum. Culms to 45 cm tall; leaf blades pilose. While we have seen no East TX specimens
of this variety, it is included based on citation for Leon and Robertson cos. by Turner et al.
(2003), for e TX by Freckmann and Lelong (2003a), and for TX by Gould and Clark (1978); se
U.S. from VA s to FL w to TX. [D. leucoblepharis (Trin.) Gould & C.A. Clark var. pubescens
(Vasey) Gould & C.A. Clark, Panicum laxiflorum Lam. var. pubescens Vasey, Panicum strigosum
(Muhl. ex Elliott) Freckmann] 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 variety to be
of conservation concern in TX. �
Dichanthelium tenue (Muhl.) Freckmann & Lelong, (slender, thin), SLENDER PANIC GRASS. Culms
to only 40(–55) mm or less tall, delicate, � 1 mm thick, erect from geniculate base, with only 3–
4 leaves; nodes glabrous; ligule � 1 mm long; leaf blades with white cartilaginous margins;
spikelets 1.3–1.7 mm long. Wooded areas, savannahs, sandy soils; Hardin (BRIT), Liberty (BRIT,
SBSC—Marysee Prairie), Angelina, Polk, San Augustine, and Tyler (TAES, annotated by S. Hatch
as D. dichotomum var. unciphyllum) cos., also Freckmann and Lelong (2003a) mapped a number
of localities in the s Pineywoods; se U.S. from MD s to FL w to TX. Spring, also fall. [D. dichotomum
(L.) Gould var. tenue (Muhl.) Gould & C.A. Clark, D. dichotomum var. unciphyllum
(Trin.) Davidse, D. ensifolium (Baldwin ex Elliott) Freckmann & Lelong var. unciphyllum
(Trin.) B.F. Hansen & Wunderlin, Panicum acuminatum Sw. var. unciphyllum (Trin.) Lelong,
Panicum dichotomum L. var. tenue (Muhl.) C.F. Reed, Panicum dichotomum var. unciphyllum
(Trin.) Wipff & S.D. Jones, Panicum tenue Muhl., Panicum trifolium Nash, Panicum
unciphyllum Trin.] This species has had a complex nomenclatural history. It has been variously
recognized as a variety of several different species (e.g., Hatch 2002—D. dichotomum var.
“uncephyllum”) or as a distinct species. It is similar to D. dichotomum and D. sphaerocarpon and
is closely related to and perhaps intergrades with D. ensifolium (Freckmann & Lelong 2003a).
The pattern of variation within this group is so complex that the rank at which to recognize
taxa seems almost arbitrary. Until further research can be done on the whole group, we are following
the recent Flora of North America treatment (Freckmann & Lelong 2003a) in treating
this taxon at the specific level.