=Squirrel-tail Grass.= _Hordeum jubatum_ L. Spikelets in clusters of three, central one only fertile, 5 mm. long, containing a grain adhering to the floral glume and palea, the other two abortive, seven awns in these three spikelets, 4-6 cm. long, four others less than 1 cm. long; awns and fragment of rachis holding the cluster of spikelets together, all barbed upward, making them troublesome for fleeces of sheep and the mouths of animals eating them. Native of this country and widely distributed.
=Old Witch Grass. Tickle Grass. A Tumble-Weed.= _Panicum capillare_ L. Florets flattened, elliptical, apex abruptly pointed, about 1.5 mm. long, highly polished, leaden gray, lighter at the extremities and along the edges of the glume, five slender light colored nerves join the extremities passing vertically over the glume, two light nerves on the palea. Native to this country.
=Tall Smooth Panicum. Switch Grass.= _Panicum virgatum_ L. Achene surrounded by two persistent shining pieces, the floret; floral glume hard, light brown, oval or ovate-lanceolate 2.5-3.1 mm. long. Apex obtusely pointed. Seldom troublesome, widely distributed.
=Low Spear-Grass.= _Poa annua_ L. Florets straw-colored, 2.8-3.1 mm. long, apex smooth, lower half of keel and the base of lateral nerves, having numerous soft hairs. A low annual grass, introduced from Europe.
=Flat stemmed Poa. Wire Grass. Canadian Blue Grass.= _Poa compressa_ L. Florets lance-obovate, 2-2.5 mm. long, closely resembling those of Poa pratensis, which see.
Palea abruptly acute. If well rubbed after threshing, the floret is nearly smooth, otherwise it contains on the lower half numerous webby hairs. Grain reddish brown, both ends pointed, 1-1.4 mm. long. Seldom sown purposely. Sometimes used to adulterate Poa pratensis. In early days this grass was called blue grass by people of New England and New York State. Introduced from Europe.
=June Grass. Kentucky Blue Grass.= _Poa pratensis_ L. Florets ovate-lanceolate, acute 3-4 mm. long, with three equal sides when seen in transverse section, nearly smooth, if severely rubbed in threshing, otherwise the floral glume is thickly webbed at the base; palea acuminate, grain light brown, elliptical, both ends usually pointed 1.2-1.4 mm. long, in cross sections with three equal sides, one of which has a shallow vertical groove. Compare with Poa compressa. Introduced from Europe.