(Poaceae) A monocotyledo-nous family containing the grasses, which number about 9000 species in about 620 genera. Grasses generally have long narrow parallel-veined leaves inserted distichously on a round hollow stem. The inconspicuous flowers are usually borne in a terminal panicle, spike, or raceme consisting of a number of spikelets. Each flower is surrounded by two bracts. The fruit is a * caryopsis. Grasses are the dominant vegetation in savannas, prairies, and steppes (see grasslands). Economically they are the most important family of plants as they contain all the cereals, which are man's staple diet. Wheats (Triticum), maize (Zea mays), rice (Oryza saliva), barley (Hordeum vulgare), oats (Avena sativa), rye (Secale cereale), sugar cane (Saccharum officinarum), and sorghums {Sorghum) are all grasses. They are also widely planted for pasture and fodder. |
