Perennial grasses with usually long narrow leaves, and terminal and axillary racemes. Spikelets in pairs at each node of the jointed hairy rachis, one sessile and perfect, the other with a pedicel, staminate, empty, or reduced to a single scale, or sometimes wanting. Perfect spikelet consisting of 4 scales, the outermost coriaceous, 2-keeled, the second keeled and acute, the two inner hyaline, the fourth more or less awned and subtending a palet and perfect flower. Stamens 1-3. Grain free. [Greek, in allusion to the bearded rachis.]

About 150 species, widely distributed in tropical and temperate regions. Besides the following, some 25 others in southern and western North America Type species: Andropogon hirtum L.

Pedicellate spikelets empty, of 1 or 2 scales, much smaller than the sessile spikelets, or wanting.

Stamen 1; racemes, or some of them, included in the spathes; rachis internodes slender.

Sheaths at the upper part of the culm not enlarged; racemes equally exserted.

Inflorescence oblong; branches divided into corymbiform masses.


A. glomeratus.

Inflorescence long, linear, little divided, not corymbiform.


A. virginicus.

Sheaths at the summit or upper part of the stem much enlarged; racemes on one of

branches exserted much beyond the others.


A. Elliottii.

Stamens 3; racemes usually exserted beyond the spathes; rachis internodes stouter.

Intercarinal space of the first scale of the sessile spikelet nearly nerveless; terminal hairs

of the internodes about twice their length.


A. ternaruis.

Intercarinal space with 2 or 3 nerves running the length of the scale; terminal hairs of the

internodes about equaling them in length.


A. Cabanisii.

Pedicellate spikelets staminate, of 3 or 4 scales, equaling or exceeding the sessile spikelets.

Rachis internodes copiously pubescent with long hairs.

Awn perfect, with a defined column; culms tufted, or with short rootstocks.

Sessile spikelets hispidulous; rachis hairs 1" long or less.


A. furcatus.

Sessile spikelets mostly glabrous; rachis hairs 1 1/2" - 2" long, yellow.


A. chrysocomus.

Awn imperfect, rarely spiral at the base; rootstocks long, horizontal.


A. Hallii.

Rachis internodes glabrous, or with a few weak crimped hairs.


A. paucipilns.