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

820 POACEAE/ANDROPOGON
AA C3 genus of 29–36 species of temperate and subtropical areas of both hemispheres and
tropical mountains, with its main distribution in sw Asia (Dogan 1999; Crins ined.). Some are
important fodder plants while others are weeds. It is unusual in lacking both paleas and lodicules
(Tucker 1996). (Greek: alopex, fox, and oura, tail, in reference to the appearance of the inflorescence)
(subfamily Pooideae, tribe Poeae)
REFERENCES: Naylor 1972; Tucker 1996; Dogan 1997 [1998], 1999; Crins ined.
1. Spikelets 1.8–2.5(–3.1) mm long; glumes hispid-ciliate on midvein from base to apex; awn of
lemma 3–5 mm long; anthers less than 1 mm long; species widespread in East TX __________ A. carolinianus
1. Spikelets 4.5–7 mm long; glumes with cilia on midvein only near base; awn of lemma 5–8+ mm
long; anthers 2–4 mm long; species rare, if present, in East TX __________________________ A. myosuroides
Alopecurus carolinianus Walter, (of Carolina), CAROLINA FOXTAIL, TUFTED MEADOW FOXTAIL,
COMMON FOXTAIL, TUFTED FOXTAIL. Culms 7–35(–60) cm tall; inflorescence 2–7 cm long and 4–6
mm in diam.; glume keels not winged. Ditches and other moist open areas; widespread in e 1/2
of TX; widespread in the U.S., particularly the southeast, also sw Canada. Mar–Jun.
Alopecurus myosuroides Huds., (resembling a mouse-tail), MOUSE FOXTAIL, SILM-SPIKE FOXTAIL,
SLENDER MEADOW FOXTAIL, BLACK-TWITCH. Culms 40–70(–85) cm tall; inflorescence 3–10(–14)
cm long, 4–8 mm in diam.; glume keels winged. Moist areas; included based on citation for
Pineywoods by Hatch (2002), Hatch et al. (1990), and for “e. Tex.” by Correll and Johnston (1970);
however, no East TX specimens have been located (e.g., BRIT, TAES, TEX), and this species is
only questionably included as a member of the East TX flora; no county distribution map is
provided; also Gulf Prairies and Marshes (Hatch 2002); scattered in e U.S. from ME to SC w to
KS and NM, also CA, OR, and sc Canada. Mar–Jun. Native of Eurasia. Apparently brought in
with hay and occurring “only as a waif” (Correll & Johnston 1970). This species is a serious
weed of grain fields in Europe (Naylor 1972; Tucker 1996; Holm et al. 1997) and is considered
noxious in NC and WA (Kartesz 1999). � I
ANDROPOGON L. BLUESTEM, BEARD GRASS
Perennials; culms stiffly erect; ligule membranous; leaf blades 10 mm or less wide; inflorescences
terminal and axillary, sometimes appearing paniculately arranged, each inflorescence
of 2–several racemose, digitately arranged branches, the peduncle subtended by, and often
partly enclosed by, a sometimes sheathing bract; spikelets in pairs: one sessile and perfect, the
other pedicellate and staminate or neuter, well-developed to rudimentary or absent (represented
by pedicel only); disarticulation so that sessile spikelet falls with associated pedicel and
section of the inflorescence branch; lower glume large, firm, tightly clasping or enclosing upper
glume; perfect spikelet with 2 florets, the lower neuter, often vestigial; lemma of perfect (upper)
floret awned or awnless.
AA genus of ca. 120 species (Campbell 2003) of tropical and warm areas of the world; it is considered
one of the dominant savannah genera (Clayton & Renvoize 1986). A number of species
are significant weeds, while others are valued as fodder or as native pasture grasses (Watson &
Dallwitz 1992). It has sometimes been circumscribed more broadly to include such genera as
Bothriochloa, Dichanthium, and Schizachyrium. Like all members of the Andropogoneae, it is
characterized by C4 photosynthesis (Kellogg 2000a). As is the case with many other warm season
C4 perennial grass species, symbiotic relationships between Andropogon species and mycorrhizal
fungi are often very important (Wilson & Hartnett 1998). The bluish tinge of the foliage
of some flowering individuals is the source of the common name BLUESTEM; at other times of
the year, the foliage can be variously colored. Members of the A. virginicus complex (including
A. glomeratus, A. gyrans, and A. virginicus) often have cleistogamous (= unopened, self-pollinated)
flowers with only a single anther. These self-fertilizing forms are often very successful at