The Encyclopedia Americana (1920)/Andropogon

ANDROPOGON, ăn'drọ-pō'gŏn, a genus of about 200 species of grasses of very diverse utility, distributed widely, especially over dry plains throughout the temperate and tropical zones. The species are usually characterized by long, narrow leaves; terminal and axillary spikes; sessile perfect spikelets paired with pedicelled staminate, empty ones or scales; and straight or twisted awns. A. halepensis, or Sorghum halepense of some authors, Johnson grass, attains a height of from three to six feet from stout, perennial creeping rootstocks, which being difficult to eradicate make the plant a troublesome weed where not needed for pasture or hay, for which it is largely grown in South America, Australia and the southern United States, where it was introduced about 1830. It makes quick growth, yields abundantly and may be cut several times in a season. It is not fully hardy in the North, where, as in Europe, it is often grown for ornament. A. schœnanthus, lemon grass, and A. nardus, citronella grass, are handsome tropical species cultivated in India and Ceylon for the fragrant oils they contain, and which are used in perfumery, soap-making and in the former case for the adulteration of certain perfumes, notably attar of roses. A. sorghum, or Sorghum vulgare of some authors, is of wide economic importance, its numerous varieties or sub-species being cultivated for fodder, sugar, alcohol, brushes, brooms and its seeds, which last are used for poultry, stock, and human food (see Sorghum). A. provincialis, A. scoparius and various other species known as blue-stem grass, are valued as fodder grasses in arid regions where they are native.