. An illustrated flora of the northern United States, Canada and the British possessions, from Newfoundland to the parallel of the southern boundary of Virginia, and from the Atlantic Ocean westward to the 102d meridian. Botany; Botany. 2l8 GRAMINEAE. Vol. I. 53. AVENA L. Sp. PL 79. 1753. Annual or perennial grasses, with usually flat leaf-blades and panicled spikelets. Spike- lets 2-many-flowered, or rarely i-flowered; lower flowers perfect, the upper often staminate or imperfect. Scales 4-many (rarely 3) ; the 2 lower empty, somewhat unequal, membranous, persistent; flowering scales deciduou
. An illustrated flora of the northern United States, Canada and the British possessions, from Newfoundland to the parallel of the southern boundary of Virginia, and from the Atlantic Ocean westward to the 102d meridian. Botany; Botany. 2l8 GRAMINEAE. Vol. I. 53. AVENA L. Sp. PL 79. 1753. Annual or perennial grasses, with usually flat leaf-blades and panicled spikelets. Spike- lets 2-many-flowered, or rarely i-flowered; lower flowers perfect, the upper often staminate or imperfect. Scales 4-many (rarely 3) ; the 2 lower empty, somewhat unequal, membranous, persistent; flowering scales deciduous, rounded on the back, acute, generally bearing a dorsal awn, the apex often 2-toothed. Palet narrow, 2-toothed. Stamens 3. Styles short, distinct. Stigmas plumose. Grain oblong, deeply furrowed, enclosed in the scale and palet, free or sometimes adherent to the latter. [Old Latin name for the Oat.] About 50 species, widely distributed in temperate regions, chiefly in the Old World. Type species: Avena sativa L. Spikelets, exclusive of the awns, 8" long or more; annuals. Flowering scales more or less hispid, the awn with a pronounced spiral column; rachilla hispid. i. A. fatua. Flowering scales glabrous, awnless or with a straight awn slightly spiral at the base. 2. A. sativa. Spikelets, exclusive of the awns, less than 8" long; perennials. Empty basal scales much shorter than the spikelet; flowering scales herbaceous, with the awn inserted near the apex. Flowering scales with a ring of hairs at the base; awn equalling or exceeding the scale. 3. A. Torreyi. Flowering scales naked at the base ; awn not more than ^ as long as the scale. 4. A. Smithii. Empty scales, at least the second one, as long as the spikelet or nearly so ; flowering scales scari- ous and hyaline above, the awn inserted about the middle. 5. A. i. Avena fatua L. Wild Oat. Fig. 526. Avena fatua L. Sp. PI. 80. 1753. Culm l°-4° tall, erect, simple, stout, smooth and gla- brous. Sheaths smoo
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectbotany, bookyear1913
