Grasses are large group angiosperms that are of great importance to man. Strictly speaking, grasses only include those species belonging to the family Gramineae but the name applies to any plant with a similar growth habit, for example, sugar cane and bamboo. Grasses also include cereal crops, such as wheat, rice, corn, sorghum and millet. Grasses are self or wind pollinated and have hollow or pithy jointed stems bearing lanceolate leaves. The fruit is a grain. Grasses provide about 53% of the total feed units (forages and grains) consumed by all domestic livestock, in the form of pastures, native range grazing and harvested forage (hay, green feed and grown silage). Grasses have other roles like in the conservation of soils, in the development and conservation of water resources,in upstream flood control, in wildlife and game management and in a wide range outdoor recreation. Grass species may be annual or perennial. Some perennial species are perpetuated by creeping stems as well as by seeds. Stems that creep underground are termed rhizomes or mot stocks, whereas surface- creeping stems are called runners or stolons. In sub- humid to semi-arid regions, species are predominantly perennial and are perpetuated mostly by seed. In other areas, both annuals and perennials occur. All grasses have fibrous root system that permeates the soil extensively, making grass effective in preventing soil erosion and restoring soil humus content.
