pound spikes; empty glumes nearly equal, longer than the flowering glumes, equaling the small lateral awns; awns unequal, the long middle awn horizontal, soon becoming reflexed. Common in dry, sterile or clay soil southward.

A. oligantha is a tufted annual, bearing loosely, fewflowered racemes, leaves short; awns all diverging and alike. Common in dry fields, especially southward; occurring as far north as Iowa. A. fasciculata is the sand grass of the plains. It is a perennial with long, spiked panicles.

Nimble Will (Muhlenbergia racemosa, (Michx.) B. S. P.). A rather stout, upright perennial, with very rough, densely scaly rootstocks, and nearly simple stems, two to three feet high; densely flowering panicles two to four inches long, contracted into an interrupted, long-peduncled spike with sessile branches; long acuminate-pointed outer glumes nearly equal and exceeding the very acute flowering glume, which is densely bearded at the base; blooms from July to September. Occurs in the northern Mississippi valley, a rapid grower and affords some forage when young. Troublesome weed.

Mexican Drop Seed (Muhlenbergia mexicana, (L.) Trin.).—An upright or ascending, usually much-branched perennial, one to three feet high, with a scaly, creeping rootstock, numerous flat leaves and contracted, densely flowered panicles; sheaths smooth; leaf blades two to seven inches long; panicles lateral and terminal, often included at the base, densely spike-clustered, linear, green and purplish; spikelets on very short pedicels, the empty glumes nearly equal, about the length of the floral glume, rough on the keel, floral glume lanceolate, acute or mucronate-pointed, three-nerved; blooms in August. Widely distributed and abundant in all parts of the state; somewhat variable in form, approaching at times the marsh Muhlenberg in density, but when cut off before

heading, the spikes become more slender, and the plant might be readily mistaken for another species. The grass matures rapidly and affords early forage, but later becomes woody. In cultivated gardens and fields it is a troublesome weed. The wild timothy (M. racemosa) has thick spikes-common weed in low grounds.

Marsh Foxtail (Alopecurus geniculatus, L.).-A slender perennial, more or less decumbent and branched at the base; lower joint bent abruptly, stem finally ascending, or erect, six to twenty-four inches high; leaves rather short, spreading and flat, upper leaf as long as its sheath; leaf blades generally smooth, lower three to six inches long, upper shorter; panicles spikelike and densely flowered, one to three inches long, with spikelets strongly compressed laterally; empty glumes rather obtuse, hairy at the keels; flowering glume awned near the base, awns very slender, nearly twice as long as the glume; sheaths smooth, Fig. 91. Muhlenbergia racemosa. a, spikelet with the upper somewhat inflated; long, acuminate-pointed outer blooms from May to Septemglumes; b, flowering glume, ber. Found in wet meadows, bearded. (Div. of Agros., U.S. Dept. Agrl.) along the banks of rivers, streams and ditches very generally throughout the United States; common along the Mississippi and Missouri rivers, waste places and fields in Missouri.

Sheathed Rush Grass (Sporobolus vaginiflorus, Wood).

-A slender annual growing one to three feet high, forming mats or turf; leaves very narrow, short and simple, few-flowered, terminal and axillary, spikelike panicles about one inch long and mostly inclosed in the somewhat inflated leaf sheaths; spikelets short; blooms in August and September. Rather common in dry fields and waste places, especially toward the South.

Small Rush Grass (Sporobolus neglectus, Nash).-A smooth, erect annual from six to twelve inches high, springing from a usually decumbent base, slender often, much-branched; sheaths about half as long as the internodes and inflated; leaves narrow at the base, smooth beneath, rough and hairy near the base above, attenuated into a slender point, lower leaves elongated, the upper one to three inches long and dry; terminal panicle one to two and one-half inches long, usually more or less included in the upper sheath; lateral panicles inclosed in the sheaths; blooming period in August and September. Very generally distributed in eastern North America.

Red Top (Agrostis alba, L.).—A well-known perennial of exceedingly variable habits, with a smooth stem that is either erect or decumbent; roots at the base or puts out stolons; from one to three feet high; sheaths smooth; leaf blade linear or narrow-lanceolate, four to eight inches long and smooth; panicle narrow, with erect, rather densely flowered branches, or lax and open, with widely spreading branches; spikelets nearly sessile, or sometimes with pedicels; flowering glumes slightly shorter than the empty glumes. Blooms from June to September. Common throughout the United States excepting in the extreme South. Found very generally in the North, usually growing on low grounds and is an excellent forage plant. Sometimes troublesome in oat fields.

Wild Oats (Avena fatua, L.).-An erect, smooth annual, three to five feet high, with flat leaves and spreading panicles of large oatlike, two to four-flowered spike

lets; flowering glumes covered with long, brownish hairs and each bears a bent awn nearly twice as long as the spikelets; blooms from June to September. Abundant,

Fig. 92. Crowfoot grass (Eleusine indica). (U. S. Dept. Agrl.)

especially in the northern states, and in the Rocky Mountains, and although much esteemed as a forage plant in some sections of the country, notably in California, it is a pernicious weed in grain fields.

Wire Grass (Eleusine indica, Gaertn.).-A coarse, tuft

ed annual, with erect or spreading, flattened stems, six to twenty-four inches high; sheaths compressed and somewhat hairy; leaf blade long and narrow, both surfaces being smooth, as a rule, although the upper side is occasionally rough and thinly hairy; spikes five to seven, widely spreading, arranged at the apex of the stem in the manner of the fingers of the hand (digitately), often with one or two branchlets below the apex, two to four inches long, greenish; spikelets three to six-flowered; glumes pointless; terminal flower a mere rudiment; seeds inclosed within a thin, loose pericarp; blooms from June to October. Found on both waste and cultivated ground, and although an introduced grass, has been naturalized in the South and in the East.

Southern Spear Grass (Eragrostis pilosa, (L.) Beauv.). -An annual, growing five to eighteen inches tall, with erect or ascending stem, diffusely branched near the base; sheaths somewhat bearded at the throat, otherwise smooth; leaves narrow, flat and smooth, but folding back on the midrib when dry; panicle elongated, three to twelve inches long, widely spreading primary branches very loose, solitary, or two or three together; spikelets narrow, lanceolate, at length becoming linear, three to fifteen-flowered, mostly much shorter than their hairy pedicels, although sometimes exceeding them in length; glumes all ovate and acute, flowering ones three-nerved; grain long; blooms from June to October. A common roadside weed in all parts of the Mississippi valley, occurring most frequently in sandy, sterile ground, but found also on railroad embankments and especially abundant in flood plains of streams.

Candy Grass (Eragrostis megastachya, (Koeler) Link). -A rather showy, much-branched annual with erect, or ascending stems, six inches to three feet high; sheaths smooth but hairy at the throat; ligules (projections from the upper part of the sheath) mere fringes of short hairs;