Tropical Grasslands (1992) Volume 26, 2529
Responses to fertiliser sulphur applied to old stands of leucaena
J.H. PRINSEN, J.D. MULLALY and G.B. ROBBINS
Queensland Department of Primary Industries, 'Brian Pastures' Research Station, Gayndah, Queensland, Australia
Ageing stands of leucaena growing on clay soils in sub-tropical south-east Queensland were observed to have lost vigour and often had pale and yellow leaves. Sulphur (S) deficiency was suspected. Thus, responses in leaf yield to S applied to 8–12 year old leucaena on a black earth soil were measured in three successive experiments, each lasting one growing season. The second experiment included leucaena grown with and without irrigation, on a prairie soil as well as the black earth. Phosphate-extractable S in the soil profiles was marginal for legume growth.