Forage yield and soil improvement potential of some annual and short-term perennial legumes at two sites in Ghana

Six annual and semi-perennial legumes were evaluated for forage production and their effect on soil properties at two sites, Pokoase (transition zone) and Nyankpala (Guinea savanna zone). The common legumes evaluated at the two sites were Lablab purpureus, Desmodium distortum, Crotalaria ochroleuca, and Macroptilium lathyroides, whilst Clitoria ternatea was additionally evaluated at Nyankpala and Mucuna pruriens was additionally evaluated at Pokoase. Herbage yields and herbage chemical composition were determined at the two sites. Soils under the different legumes at Pokoase were also analysed for nitrogen, extractable phosphorus, exchangeable potassium, and organic carbon contents. The large-leaved climbing and decumbent species L. purpureus and M. pruriens as well as the erect M. lathyroides showed very good attributes in forage production and soil improvement properties. Herbage yields in the three species at the Pokoase siteexceeded 6 t/ha and produced high crude protein contents in the range 14.71 to 17.38 per cent. The soils under L. purpureus and M. pruriens showed high N contents (> 0.5 per cent) whilst M. lathyroides improved soil organic carbon best. Macroptilium lathyroides also showed the highest contents of available P and exchangeable K in soil under it compared to the other legumes. Ghana Jnl.agric. Sci Vol.32(1), 1999: 47-5