| Neil Snow |
Plants perennial; usually dioecious;
strongly stoloniferous, sometimes mat-forming. Culms 1-30 cm, erect,
solid, mostly unbranched, those of the pistillate inflorescences much shorter
than those of the staminate inflorescences; nodes mostly glabrous. Leaves
basally tufted, not clustered or strongly distichous; sheaths open, rounded,
often sparsely pilose near the collar; ligules membranous or of hairs;
blades usually flat basally, curling when dry, glabrous or sparsely pilose,
apices involute. Staminate inflorescences terminal, usually exceeding
the upper leaves, panicles of 1-3(4) racemosely arranged, unilateral, pectinate
branches; branches not enclosed at maturity, spikelets densely crowded
in 2 rows. Staminate spikelets with 2 florets; glumes unequal,
glabrous, 1- or 2-veined; lemmas 3-veined, glabrous, unawned; anthers
brownish to red or orange. Pistillate inflorescences terminal, panicles,
partially hidden within bracteate leaf sheaths; branches 2-3(4), 2.5-4.5
mm, burlike, with 3-5(7) spikelets; disarticulation at the base of the
panicle branches. Pistillate spikelets with 1 floret, almost completely
enclosed by the upper glumes; lower glumes irregular and reduced; branch
axes and lower portion of upper glumes globose, white, indurate,
terminating in 3 awnlike teeth; lemmas firmly membranous, glabrous, 3-veined,
unawned or shortly 3-awned. x = 10. Name a contraction of Bubalochloë,
from the Greek boubalos, buffalo, and chloë, grass.
Buchloë is a monotypic genus of the central plains of North America.
It is usually dioecious, infrequently monoecious, or rarely synoecious. On the
basis of his molecular studies, Columbus (1999) recommended including it and
several other small, usually monoecious or dioecious genera in Bouteloua.
Morphologically, the segregate genera differ from Bouteloua only in their
pistillate panicles and spikelets and their reproductive mode, but not in their
vegetative and staminate structures. Buchloë is maintained here
pending corroboration from other studies.
1. Buchloë dactyloides (Nutt.) Engelm.
Buffalograss
Ligules 0.5-1 mm; blades 2-15 cm long, 1-2.5
mm wide. Staminate spikelets 4-6 mm long, 1.3-1.8 mm wide; anthers
2.5-3 mm. Pistillate spikelets to 7 mm long, about 2.5 mm wide. Caryopses
2-2.5 mm. 2n = 20, 40, 56, 60.
Buchloë dactyloides is a frequent dominant on upland portions of
the semi-arid, shortgrass component of the Great Plains, ranging from the southern
prairie provinces of Canada through the desert southwest of the United States
to much of northern Mexico. Collections from east of the Mississippi River and
south of the Ohio River probably represent recent introductions.
Buchloë dactyoides provides valuable forage for
livestock and wildlife, and withstands heavy grazing. It may be confused in
the southern portion of its range with Hilaria
belangeri, which consistently has pilose nodes, or in the Big Bend region
of Texas with Cathestecum erectum,
which has three spikelets per node and distinctly awned lemmas.