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

958 POACEAE/HOLCUS
Auguste François César Prouvençal de St.-Hilaire, 1779–1853, French botanist, explorer, and entomologist—Barkworth
2003g) (subfamily Chloridoideae, tribe Cynodonteae)
REFERENCES: Cory 1948; Brown & Coe 1951; Sohns 1956; Scholl & Kinucan 1996; Columbus et al.
1998; Barkworth 2003g.
Hilaria belangeri (Steud.) Nash, (named for Charles Paulus Bélanger, 1805–1881), COMMON CURLY-
MESQUITE. Low tufted perennial 10–35 cm tall, with slender stolons that produce new tufts;
nodes densely bearded with spreading hairs; ligule a membrane 0.5–3 mm long; leaf blades 1–
2(–3) mm wide, short and often forming a curly tuft, but sometimes longer and erect; inflorescence
a slender, bilateral, pedunculate spike 2–3.5(–4) cm long, with 4–8 clusters of 3 spikelets
each, the clusters usually 4.5–6(–8) mm long, each deciduous as a unit; central spikelet fertile, 1flowered;
lateral spikelets staminate, 2(–3)-flowered; glumes united below, usually asymmetrical;
glumes of central spikelet with awns usually 2.5–5 mm long; lemmas awnless. Open
brushy and rocky areas, usually on calcareous soils; Bell, Bexar, Travis (BRIT), Comal, DeWitt,
Hays, Williamson, and Wilson (Turner et al. 2003) cos.; w and sw boundaries of East TX w
through w 2/3 of TX; AZ, NM, and TX. (Mar–)Aug–Oct(–Nov). This species was the dominant
grass on the shortgrass prairies of TX (Barkworth 2003g). It is one of the few species which increases
in dominance under heavy grazing, and it is considered a valuable forage grass in c and
w TX (Brown & Coe 1951; Scholl & Kinucan 1996). It can be confused with Buchloe dactyloides
(BUFFALO GRASS), but H. belangeri has consistently bearded culm nodes, while in B. dactyloides
the nodes are mostly glabrous (Snow 2003c).
HOLCUS L. VELVET GRASS
AA C3 genus of 8 species native to Europe, North Africa, and the Middle East (Standley ined.);
some are considered significant weed species (Watson & Dallwitz 1992). It is apparently related
to Deschampsia, HAIR GRASS (Clayton & Renvoize 1986). (Latin: holcus, old name for a kind of
grain—Hitchcock 1951) (subfamily Pooideae, tribe Poeae)
REFERENCES: Beddows 1971; Thompson & Turkington 1995; Tucker 1996; Standley ined.
Holcus lanatus L., (woolly), COMMON VELVET GRASS, YORKSHIRE-FOG, CREEPING SOFT GRASS. Tufted
or clumped perennial; culms 35–100(–150) cm long, erect, sometimes spreading basally; culms
(particularly adjacent to the lower nodes) and leaves densely soft-hairy, velvety to the touch;
ligule a ciliate membrane 1.5–4.5 mm long; leaf blades flat, usually 4–10(–12) mm wide; inflorescence
a dense panicle 4–15(–20) cm long; spikelets 3.5–5.5(–6) mm long, with 2 florets, disarticulating
below the glumes; glumes subequal, 3–5.5(–6) mm long, exceeding rest of spikelet in
length, ciliate on keel and veins, sometimes with short hairs between the veins; lower floret perfect,
awnless, ca. 2 mm long, glabrous; upper floret staminate, with lemma awned from below
apex, the awn 1–2 mm long, curled or hooked at maturity; paleas slightly shorter than lemmas.
Disturbed areas, marshes; scattered in East TX in Harrison, Robertson (BRIT), and Rusk (Turner
et al. 2003) cos.; also Pecos Co. (Turner et al. 2003) in the Trans-Pecos and reported for Gulf Prairies
and Marshes (Gould 1975b; Hatch 2002) but vouchers not seen; e and sw Canada (B.C.) and
throughout most of the U.S. May–Jun. Native of Europe widely naturalized in the U.S. and most
other temperate areas. [Nothoholcus lanatus (L.) Nash] This species was “widely distributed in
North America by 1800” (Standley ined.). It has been reported to be a potential cause of hydrocyanic
acid poisoning (Fuller & McClintock 1986), but Tucker (1996) indicated that it is not
cyanogenic. However, it is poor forage and ingestion has been reported to cause inflammation
of mucous membranes of the mouth (Tsvelev in Tucker 1996). It can also cause hay fever where
abundant (Yatskievych 1999). The foliage is distinctly velvety to the touch. � I
HORDEUM L. BARLEY
Mostly annuals (in East TX) or, in case of H. jubatum, perennial; leaves with or without auricles;
ligule a membrane; inflorescence a dense, 2-sided spike or spike-like raceme, breaking apart in