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leaf blade flat, three to ten i::ches long, rather rough on the upper surface; panicle elliptical or oblong, branches usually spreading; spikelets three to ten inches long, seven to forty-flowered, becoming whitish when old; flowering glumes very prominently nerved and rough on the keel; emits an unpleasant odor; blooms from June to October. A weedy grass, common in fields and gardens across the continent.

Wire Grass (Poa compressa, L.).--Sometimes called English blue grass, a pale, slender, but rather rigid, perennial, with a much flattened stem, six to twenty inches high, ascending from a more or less creeping rootstock; dense narrow panicles somewhat one-sided, one to three inches long, short branches mostly in pairs; pedicels shorter than the spikelets, which are lanceolate, five to nine-flowered and flattened; blooms from June to September. A native of Europe, but extensively naturalized in this country; found in nearly all parts of the North, growing in dry, sterile places and waste lands; an excellent forage plant, but yields less than blue grass.

Cheat or Chess (Bromus secalinus, L.).-An erect annual growing from two to three feet tall; generally smooth, occasionally pubescent at the nodes; sheath striate, usually smooth; rather broadly linear leaf blade from six to twelve inches long, smooth beneath and more or less rough or pilose on the upper surface; flowers arranged in panicles, from four to eight inches long, erect, the more or less compound branches spreading even in fruit; spikelets from six to ten lines long, and six to twelve-flowered, drooping in fruit; first empty glume three to five; second, seven-nerved; flowering glumes obscurely seven-nerved, smooth or minutely downy along the margins and near the apex, becoming cylindrical in fruit; blooms in July and August. A well-known weed of grain fields, found in all parts of the wheat-growing sections of the country.

Soft Chess (Bromus hordeaceus, L.).-An erect, usually slender, pubescent annual, growing one to three feet high, with flat leaves and contracted panicles, which are one to three inches long; the three to eight-flowered spikelets are one-half to one inch long, with pubescent glumes; flowering glumes obtuse and with awns somewhat shorter than the glumes; blooms from May to August. Introduced and found along railroads, and in the streets of cities, and in fields and waste places in the North ; nearly worthless as a forage plant. Downy Brome Grass (Bromus tectorum, L.).-A slender, erect, leafy annual seven to twenty-five inches high, with narrow, softly pubescent leaves and open, nodding panicles, three to seven inches long; spikelets each five to eight-flowered, with unequal, acuminate-pointed, hairy, empty glumes, and rough or hairy glumes, four to six lines long; awns six to eight lines long; blooming period from June to August. First introduced into the United States from Europe, and is without forage value; while not greatly troublesome in Iowa or eastward, it has become a serious pest farther west in Utah and Colorado. Poison Darnel (Lolium temulentum, L.).—An annual with a smooth, stout stem from two to three feet tall; rough sheaths and a spike from six to twelve inches long; spikelets five to seven-flowered, the sharp-pointed empty glumes as long as the spikelets; flowering glumes turgid, awned or awnless, and both shorter and broader than in common darnel (L. perenne); blooms from June to August; also called bearded darnel. Found in waste places and cultivated grounds in the wheat-growing sections of the country and Canada. Couch Grass or Quack Grass (Agropyron repens, (L.) Beauv.).-An introduced grass already becoming troublesome in Iowa; culms one to three feet high, arising from an extensively creeping, jointed rootstock; sheaths usually smooth; leaves from four to twelve inches long,

Fig. 93. Quack grass or couch grass (Agropyron repens). The running “roots” (rhizomes).

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smooth, scabrous or somewhat downy above; erect spikes from three to ten inches long, bearing four to eightflowered spikelets; empty glumes from five to sevennerved, sometimes notched and short-awned or acute; flowering glume nerved near the apex, awnless or shortawned. Blooming period from August to October. This grass has become naturalized on lawns and cultivated grounds and is a very common wayside pest. Little Barley (Hordeum pusillum, Nutt.).-An annual four to ten inches tall, with stems more or less jointed at the lower nodes, the uppermost being often inflated, so as to inclose the base of the spike; leaf blade from one to three inches long, usually slightly pubescent on the lower surface; spikes narrow and from one to three inches long; empty glumes rigid, the four internal glumes of each group being dilated above the base, those at the central spikelet sublanceolate, all awn-pointed; outer glumes of the imperfect, lateral spikelets bristly; flowering glumes of central spikelet awned, and florets of the lateral glumes awnless. The flowers appear from April to Au- gust. This plant has been intro- Fig. 94. Little barley duced into the southern part of Iowa. (Horée" "i"). Squirrel-tail Grass (Hordeum jubatum, L.).-An annual or winter annual, from six inches to two feet high with fibrous roots, forming solid bunches with leaves not unlike those of blue grass except in being paler; flowers appear in spikes two to four inches long, pale green or purplish; flowers with long awns which give it a bristly appearance; when mature, spikes break into joints; blooming period from June to August. Plant is propa

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Fig. 94a. Common wild barley (Hordeum Jubatum). (Photograph, Miss Charlotte M. King.)

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