Plants perennial, occasionally annual; cespitose, sometimes with short rhizomes. Culms 10-150 cm, erect, sometimes branching above the base. Leaves sometimes aromatic; sheaths without glandular pits; ligules shortly membranous and densely ciliate or of hairs; blades involute, flat, or folded. Inflorescences terminal, sometimes also axillary, composed of solitary, flexuous rames; rame internodes columnar to clavate, apices strongly oblique, not hollowed or rimmed; disarticulation in the rames, below the sessile spikelets. Spikelets in sessile-pedicellate pairs. Sessile spikelets dorsally compressed; calluses blunt, sometimes resembling a short pedicel; lower glumes enclosing the upper glumes, subcoriaceous, 2-keeled, keels prominently ciliate, intercarinal surface smooth, apices cuspidate to bilobed, rarely entire; lower florets reduced, sterile; upper florets bisexual, unawned. Pedicels stout, appressed but not fused to the rame axes, pubescent or ciliate on the angles. Pedicellate spikelets 3-8 mm, about equal to the sessile spikelets, staminate, muticous to awn-tipped. x = 5. Name from the Greek eluein, mouse, and oura, tail, alluding to the narrowly cylindrical inflorescence.

Elionurus has 15 species. Most of the species are native to tropical Africa and America; one species is Australian. Several of the species are considered important elements of native pastures, but neither of the two species native to the Flora region is ever sufficiently abundant to be important in this regard.

1.   Elionurus barbiculmis Hack.
Woolyspike Balsamscale

Plants cespitose. Culms 40-60 cm, erect, usually unbranched, densely antrorsely hirsute beneath the nodes. Sheaths mostly glabrous, often ciliate on the margins, particularly at the throat; ligules with 1-2 mm hairs; blades 15-30 cm long, 1-2(4) mm wide, usually involute, abaxial surfaces with scattered long hairs adjacent to the margins, adaxial surfaces usually densely pilose. Rames 5-10 cm, internodes densely villous. Sessile spikelets 4.5-8 mm; calluses about 0.5 mm, hirsute; lower glumes densely hirsute, acuminate, bifid, teeth 1.5-2.5 mm; pedicels densely pilose dorsally. Pedicellate spikelets with densely pilose lower glumes. 2n = 20.

Elionurus barbiculmis grows on mesas, rocky slopes, hills, and in canyons, usually above 1200 m. Its range extends from southern Arizona and southwestern Texas into northern Mexico.

2.   Elionurus tripsacoides Humb. & Bonpl. ex Willd.
Pan-American Balsamscale

Plants cespitose; with short, knotty, rhizomatous bases. Culms 60-120 cm, glabrous throughout. Sheaths glabrous or pilose on the margins; ligules 0.5-1 mm, membranous, shortly ciliate; blades 16-30 cm long, 2-4 mm wide, adaxial surfaces with hairs to 5 mm basally, glabrous distally, margins ciliate near the bases. Rames 6-15 cm; internodes pilose. Sessile spikelets 6-8 mm; calluses about 1 mm, antrorsely hirsute; lower glumes usually mostly glabrous, rarely sparsely pilose dorsally, keels ciliate distally, apices acuminate, bidentate, teeth about 0.5 mm; pedicels hispid on the margins, usually glabrous elsewhere. Pedicellate spikelets similar to the sessile spikelets. 2n = 20.

Elionurus tripsacoides grows in moist pine woods and low prairies around southern Texas and the Gulf coast to Georgia, and south through Mexico and Central America to Argentina.