Free ranging cattle in the Accra Plains of Ghana have an almost all grass diet during the rainy season when lush grass abounds (Fianu, 1966). Depending on the ecological status of the grassland, the prominent species include Andropogon gayanus, Brachiaria falcifera, Panicum maximum, Schizachyrium schweinfurthii and Vetiveria fulvibarbis. On bush fallows, grasses of lower successional status, e.g. Chloris and Digitaria spp., are grazed.
At the start of the rainy season (March-April), the young herbage may contain as much as 2.8% N. As the plant matures, however, the N content declines rapidly below critical levels, e.g. 0.95-1.3% at 18 weeks (Fianu and Winch, 1980) and 0.6-0.8% at 38 weeks (Lansbury, Rose Innes and Mabey, 1965).
Such mature grass is burnt in the dry season to induce a more nutritious flush but hard grazing and slashing also induce equally nutritious regrowth (Fianu and Winch, 1980).