26.27   HACKELOCHLOA Kuntze
John W. Thieret†

Plants annual; cespitose. Culms 20-120 cm, erect to decumbent, often rooting at the lower nodes, branching above the bases. Leaves not aromatic; sheaths open; auricles absent; ligules membranous, ciliate. Inflorescences terminal and axillary, solitary, 2-sided rames, these sometimes fascicled and partially enclosed in subtending leaf sheaths at maturity; disarticulation in the rames, beneath the sessile spikelets. Spikelets in heterogamous sessile-pedicellate pairs. Sessile spikelets hemispherical, partly embedded in the rame axes; lower glumes as long as the spikelets, indurate, alveolate, indistinctly 7-11-veined, not keeled, margins involute; upper glumes chartaceous, 3-veined, usually adherent to the rame axes; lower florets sterile; upper florets bisexual; anthers 3. Pedicels adnate to the rame axes, concealed by the sessile spikelets. Pedicellate spikelets as long as or longer than the sessile spikelets, ovate; lower glumes dorsally compressed, 5-9-veined; upper glumes laterally compressed, 5-7-veined; lower florets sterile; upper florets staminate; anthers 3. x = 7 (probably). Named for Eduard Hackel (1850-1926), an Austrian agrostologist, and the Greek chloa, grass.

Hackelochloa is treated here as a monospecific genus that is widely distributed in warm regions of the world, often as a weed. Veldkamp et al. (1986) combined it with Coelorachis, Heteropholis, Ratzeburgia, and Rottboellia formosa in Mnesithea. The traditional treatment for Hackelochloa is retained here.

SELECTED REFERENCES Allred, K.W.1993. A Field Guide to the Grasses of New Mexico. New Mexico Agricultural Experiment Station, Department of Agricultural Communications. New Mexico State University, Las Cruces, New Mexico, U.S.A. 258 pp.; Hitchcock, A.S. 1951 [title page 1950]. Manual of the Grasses of the United States, ed. 2, rev. A. Chase. U.S.D.A. Miscellaneous Publication No. 200. U.S. Government Printing Office, Washington, D.C., U.S.A. 1051 pp.; Veldkamp, J.F., R. de Koning, and M.S.M. Sosef. 1986. Generic delimitation of Rottboellia and related genera (Gramineae). Blumea 31:281-307.

1.   Hackelochloa granularis (L.) Kuntze
Pitscale Grass

Culms 20-120 cm, glabrous or hispid, with papillose-based hairs. Leaves sparsely to densely hispid throughout, hairs papillose-based; sheaths shorter than the internodes; ligules 2-3 mm; blades 3-20 cm long, 6-13 mm wide, subcordate. Rames (2)7-27 mm. Sessile spikelets 1-1.3 mm; anthers 0.3-0.4 mm. Pedicellate spikelets 1.6-2.2 mm; glumes chartaceous; lower glumes winged on 1 keel; upper glumes with the midvein narrowly winged; anthers 1-1.2 mm. Caryopses 0.7-0.9 mm, elliptic to nearly orbicular in outline, brown to yellow-brown. 2n = 14.

Hackelochloa granularis is a native of the Eastern Hemisphere that has become established in cultivated land, roadsides, and weedy areas of the southern region of the United States. Its range extends south through Mexico and Central and South America. Hitchcock (1951) reported it from New Mexico, but it is not established there (Allred 1993).