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

SCHEDONNARDUS/POACEAE
1047
lower glume ca. 1–1.7 mm long, � 1/3 as long as second, often 1/4 or less as long; lemma of fertile
floret ca. 1.5–2 mm long. Moist sand, pond margins, along streams, and in ditches; widely
scattered in East TX w to Lamar, Leon, Wood (BRIT), and Guadalupe (Turner et al. 2003) cos;
also n Gulf Prairies and Marshes; se U.S. from NJ s to FL w to MO, OK, and TX, also MA and ME.
Late Aug–Nov. [Panicum aquaticum Bosc ex Spreng.]
SCHEDONNARDUS Steud. TUMBLE GRASS, TEXAS CRAB GRASS
AA monotypic C4 genus of North America that has recently been introduced into Argentina
(Snow 2003b). Some authorities consider it related to Gymnopogon (Clayton & Renvoize 1986),
but recent molecular evidence (Hilu & Alice 2001) questions this conclusion. The inflorescence
acts as a tumbleweed, and Mabberley (1997) noted that this species is a conspicuous feature of
deserted towns in Western films. (Greek: schedon, near, and Nardus, from its resemblance to
that grass genus) (subfamily Chloridoideae, tribe Cynodonteae)
REFERENCE: Snow 2003b.
Schedonnardus paniculatus (Nutt.) Trel., (with flowers in panicles), TUMBLE GRASS, TEXAS CRAB
GRASS. Tufted perennial 8–50(–70) cm tall or long; leaves crowded toward base of plant; leaf
sheaths compressed, keeled, glabrous; ligule a membrane 1–4 mm long; leaf blades 1–3 mm
wide, spirally twisted on drying; inflorescence as long as or longer than the leafy portion of the
culm, spreading to partly decumbent, finally breaking away in its entirety and acting as a tumbleweed,
the main axis becoming loosely coiled, with a few widely spaced, spicate branches;
spikelets appressed, in 2 rows along one side of each branch, not overlapping or only slightly so,
with 1 floret, unawned, 3–5.5 mm long, disarticulating above the glumes; glumes unequal, the
upper longer. Prairies, disturbed areas, various soils; throughout TX; sc Canada and c U.S. from
MN s to LA w to MT and AZ, also CA. This was a minor member of original prairie which increases
under disturbance; rather common on disturbed or overgrazed sites. Apr–Oct.
SCHIZACHYRIUM Nees BLUESTEM, FALSE BLUESTEM
Ours perennials; ligule membranous, 3 mm or less long, sometimes fringed; flowering culms
much-branched, each leafy branch terminating in a spicate raceme (these sometimes crowded
together and sometimes appearing axillary due to the shortness of the branches of the flowering
stem); spikelets in pairs of one sessile and one pedicellate; sessile spikelets 2-flowered, the
upper floret fertile, with toothed or cleft lemma, the lower floret neuter; pedicellate spikelets
staminate or neuter; disarticulation at base of sessile spikelet so that associated pedicel and section
of inflorescence axis fall with sessile spikelet.
AA mainly tropical and subtropical genus of ca. 60 species (Wipff 2003k), particularly in
savannahs. These plants were formerly treated along with Bothriochloa in a more inclusive
Andropogon (e.g., Hitchcock 1951). However, most species of Schizachyrium differ from these
other two genera in having only one raceme per peduncle (Wipff 2003k). In addition,
Schizachyrium species have raceme internodes with cupulate tips and convex lower glumes
veined between the keels—Andropogon species lack these features (Wipff 2003k). The common
name, BLUESTEM, is derived from the bluish green color of the glaucous foliage of some plants.
Like all members of the Andropogoneae, Schizachyrium is characterized by C4 photosynthesis
(Kellogg 2000a). Several species are important native pasture grasses while some are significant
weeds (Watson & Dallwitz 1992). (Greek: schizo, to divide or split, and achna, chaff, referring to
the toothed lemma) (subfamily Panicoideae, tribe Andropogoneae)
REFERENCES: Shinners 1954; Gould 1967; Grelen 1974; Türpe 1984; Carmen & Briske 1985; Butler &
Briske 1988; Gandhi 1989; Briske & Anderson 1992; Gandhi & Smeins 1996; Wipff 1996a, 2003k.
1. Pedicels (of pedicellate spikelets) ciliate with long silvery hairs at least on the upper two-thirds;
raceme internodes relatively thin and flexuous, ciliate with long silvery hairs the entire length or