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

1098 POACEAE/WILLKOMMIA
var. octoflora, COMMON SIXWEEKS GRASS. Lemma bodies 3.5–6.5 mm long. Pineywoods and Gulf
Prairies and Marshes w to West Cross Timbers and Edwards Plateau; sw Canada and throughout
most of U.S. [Festuca octoflora Walter] This is apparently the most common variety in East TX.
Vulpia sciurea (Nutt.) Henrard, (squirrel), SQUIRREL SIXWEEKS GRASS, SIXWEEKS FESCUE, SQUIR-
REL-TAIL FESCUE. Plant 15–60 cm tall; panicles narrow, elongate, 5–20 cm long, drooping toward
tip; upper glume 2.3–4 mm long; lemmas pubescent, particularly near apex, with awn 4.5–10
mm long. Loose sandy soils; scattered in e 1/2 of TX; e U.S. from NJ s to FL w to IA and TX. Apr–
early May. [Festuca sciurea Nutt., Vulpia elliotea (Raf.) Fernald] There has been disagreement
over the correct nomenclature for this species. While it has often been known as V. elliotea (e.g.,
Gleason & Cronquist 1991; Fernald 1950a; Kartesz 1999; Yatskievych 1999), we are following a
number of recent authorities (e.g., Tucker 1996; Hatch 2002; Lonard ined.) in considering
sciurea the correct epithet if the taxon is treated in Vulpia (rather than in Festuca). Lonard
(ined.) considers this to be the most distinct Vulpia species native to North America—it has a
“narrow panicle, small spikelets, and apically pubescent lemmas.”
WILLKOMMIA Hack. WILLKOMMIA
AA C4 genus of 3 species with an unusual disjunct distribution—3 species in s tropical Africa
and one in the New World, including TX (Clayton & Renvoize 1986; Wipff 2003c). (Named for
Heinrich Moritz Willkomm, 1821–1895, student of Spanish flora and successively professor of
botany at Tharandt, Dorpat, and Prague) (subfamily Chloridoideae, tribe Cynodonteae)
REFERENCES: Hitchcock 1903; Wipff 2003c.
Willkommia texana Hitchc. var. texana, (of Texas), TEXAS WILLKOMMIA. Tufted perennial, not
stoloniferous; culms 20–40 cm tall; leaves mostly basal, the blades 1–3 mm wide; ligule a
minute fringe of cilia, 0.6 mm or less long or obsolete; inflorescence a very narrow spike-like
panicle 7–18 cm long, 3–10 mm wide, with spikelets in 2 rows along the short (ca. 2–4 cm long)
appressed branches; spikelets 1-flowered, sessile, awnless, 3.5–5 mm long, disarticulating above
the glumes; glumes glabrous, unequal, the lower glume ca. 1/2–2/3 as long as the upper,
rounded and membranous apically, the upper glume slightly longer than lemma, 1-veined,
acute; lemma with appressed hairs on back and densely appressed ciliate marginally. Bare clay
or sandy soils, sometimes in saline or alkaline conditions; Harris Co. (BRIT) at s margin of East
TX, Ellis Co. (Hitchcock 1903) in the n Blackland Prairie, and a recent Anderson Co. collection
(Keith 601, Sep 2003, open saline prairie, SBSC) in between; listed variously as restricted to the
Pineywoods and Gulf Prairies and Marshes (Gould 1975b), the Gulf Prairies and Marshes and
Post Oak Savannah (Hatch et al. 1990; Hatch 2002), or primarily Gulf Prairies and Marshes
(Carr 2001; Turner et al. 2003); endemic to TX (Kartesz 1999; Carr 2002b, 2002c), though apparently
recently introduced to OK (Wipff 2003c). The type specimen is from Ennis (Ellis Co.)
(Hitchcock 1903). Variety stolonifera Parodi, (stolon-bearing), is disjunct to Argentina. The two
varieties are similar, with var. stolonifera being stoloniferous versus tufted. Mainly Apr–Jun.
(RARE 2001, 2002b: G3G4T3S3) �E
ZEA L. MAIZE, CORN
AThe genus consists of 5 species (Iltis 2003). Four are native to Mexico and Central America,
and the fifth, MAIZE, is one of the most important New World cultivated crops. Zea is related to
Tripsacum (Clayton & Renvoize 1986). Like all members of the Andropogoneae, it is characterized
by C4 photosynthesis (Kellogg 2000a). According to Iltis (2003), “The often weedy, wild
taxa, known as ‘teosinte’ … ” have been used in plant breeding as well as in developmental, evolutionary,
physiological, and genetic research. The genus has been the subject of other important
research such as the Nobel prize-winning discovery by Barbara McClintock of “jumping genes,”
which can move from one chromosome to another. The common name is from “Spanish maiz,