Part 7 - UNC Herbarium

POACEAE 922
shelves in the fall-line sandhills; rare (GA Rare, NC Watch List, SC Rare). June-September (and into December in response to
growing-season fire). The identity of this taxon has been obscure; it is now clear that it is a previously unrecognized species,
endemic to NC, SC, and adjacent e. GA. RAB included it in their concept of S. teretifolius, though it does not key well (keying
imperfectly to either S. floridanus or S. heterolepis); in S and HC, it will key to S. floridanus, but the leaves are much narrower.
Additionally, S. floridanus is a taller and coarser plant, the culms often averaging about 1.5 meters in height and 2-3 mm in
diameter basally (vs. 1 meter high and 1 mm in diameter for Sporobolus pinetorum). In wet savannas of Columbus County, NC,
S. species 1 occurs with true S. teretifolius (the two codominant over many hectares!), and the two taxa are manifestly distinct.
The leaves of S. pinetorum are not terete; after lengthy drought in the field (or dry on an herbarium sheet), the leaves become
tightly folded to involute and can appear wiry. Like many Southeastern pineland grasses, S. pinetorum flowers only following
fire. In vegetative condition it may be distinguished from Aristida stricta and A. beyrichiana, with which it often grows, by the
leaf pubescence (S. pinetorum with scaberulous margins, best felt by running a finger along the margin near the base, from apex
toward base, A. stricta and A. beyrichiana not scaberulous, and with a sparse line of pilose hairs running more or less the length
of the leaf in A. stricta and sometimes in A. beyrichiana) and base (much more indurated and polished in Sporobolus than in
Aristida). [= FNA, K, Y; >< S. teretifolius – RAB, misapplied; > S. floridanus – RAB, misapplied; < S. floridanus Chapman –
HC, S]
Sporobolus teretifolius Harper, Wireleaf Dropseed. Cp (GA, NC, SC): wet savannas, pitcherplant bogs; rare (US Species
of Concern, GA Rare, NC Threatened). July-September (and later in response to growing-season fire). Very similar vegetatively
to Aristida stricta, S. teretifolius can be distinguished by its tuft of hairs at the base of the otherwise glabrous blade (as opposed to
line of pilose hairs the length of the blade in A. stricta). This very rare species is known only from se. NC, ne. SC, s. GA, and se.
AL (Houston County). Many of the counties reported for this species in RAB actually are based on misidentified specimens of
Sporobolus pinetorum. In a few very wet savannas of Columbus and Brunswick counties, NC, S. teretifolius is dominant or
codominant over many hectares. Like many savanna grasses, S. teretifolius generally flowers only following fire. [= FNA, HC,
K, S, Y; < S. teretifolius – RAB (also see S. pinetorum)]
Sporobolus vaginiflorus (Torrey ex A. Gray) Wood, Poverty Dropseed. Pd, Mt (GA, NC, SC, VA), Cp (VA): glades,
barrens, open disturbed sites; uncommon. September-October. The species occurs nearly throughout e. United States. S.
ozarkanus, S. neglectus, and S. vaginiflorus form a still very poorly understood complex. [= RAB, C, G, HC, W; = S.
vaginiflorus var. vaginiflorus – F, FNA, K; = S. vaginaeflorus – S, orthographic variant]
Sporobolus virginicus (Linnaeus) Kunth, Seashore Dropseed, Coastal Dropseed. Cp (GA, NC, SC): salt marshes, tidal
mud flats, and low dunes in the outer Coastal Plain; rare (NC Watch List). September-October. This species occurs from se. NC
along the coast to TX, in the West Indies and into n. South America (its alleged occurrence in se. VA is apparently incorrect).
Sporobolus virginicus is similar in aspect and growth form to Distichlis spicata, with which it occurs in tidal flats. Sporobolus
virginicus is more delicate, and typically has long hairs on either side of the collar of the sheath; Distichlis spicata is generally a
coarser plant, and lacks long hairs around the collar of the sheath. [= RAB, C, F, FNA, G, GW, HC, K, S]
* Sporobolus airoides (Torrey) Torrey, Alkali Sacaton. Cp (SC): waste areas near wool-combing mills; rare, intoduced from
, not known to be established or persistent. [= FNA, HC, K] {not keyed}
Sporobolus compositus (Poiret) Merrill var. drummondii (Trinius) Kartesz & Gandhi, ranges east to the Ridge and Valley
province of e. TN (Chester et al. 1993), occurring over limestone, and allegedly to KY and GA (Kartesz 1999). It could very
likely occur in sw. VA, as it is in Hawkins County, TN, immediately adjacent to VA (Chester et al. 1993). [= FNA, K; = S.
asper (Michaux) Kunth var. drummondii (Trinius) Vasey – C, Z; = S. drummondii (Trinius) Vasey – F, S; = S. asper var. hookeri
(Trinius) Vasey – G, HC, misapplied]
* Sporobolus fimbriatus (Trinius) Nees. Cp (SC): waste areas near wool-combing mills; rare, perhaps only a waif, intoduced
from Africa. [= FNA, HC, K] {not keyed}
* Sporobolus flexuosus (Thurb. ex Vasey) Rydberg. Cp (SC): waste areas near wool-combing mills; rare, perhaps only a
waif, intoduced from sw. United States and n. Mexico. [= FNA, HC, K] {not keyed}
* Sporobolus tenuissimus (Martius ex Schrank) Kuntze. Cp (SC): waste areas near wool-combing mills; rare, perhaps only a
waif, introduced from the tropical Old World and New World. [= FNA, K] {not keyed}
* Sporobolus wrightii Munro ex Scribner, Giant Sacaton. Cp (SC): waste areas near wool-combing mills; rare, perhaps only
a waif, intoduced from sw. United States. [= FNA, HC, K] {not keyed}
Steinchisma Rafinesque 1830 (Gaping Panic Grass)
A genus of about 6 species, perennial herbs, of s. North America, Central America, and South America. See discussion following
Panicum regarding generic concepts. References: Zuloaga et al. (1998)=Z; Freckmann & Lelong in FNA (2003a).
Steinchisma hians (Elliott) Nash, Gaping Panic Grass. Cp (GA, NC, SC, VA), Pd (GA, NC, SC), Mt (GA): stream, pond,
and lake shores, low woods, cypress-gum ponds, floodplains, marshes, ditches, seepage slopes; common in Piedmont, occasional
in Coastal Plain. May-October. Se. VA south to FL, west to TX and OK, and south through Mexico and Central America to
Colombia; also in s. South America. The large, thickened, pale sterile palea of this species is unique among panicoids of our
region; it is one of several characters that has led to the segregation of Steinchisma as a genus, or as a subgenus of Panicum. The
enlargement of the sterile palea causes the spikelet to spread open, or "gape." [= FNA, K, Z; = Panicum hians Elliott – RAB, C,
F, G, GW, HC, S, W]