JON W. BURGESS1 and CLAIRE M. BARRETT2
1Department of Natural Resources, Mackay
2Queensland Beef Industry Institute, Department of Primary Industries, Mackay, Queensland, Australia
This paper examines the relationship between soil fertility and estimated animal performance in the Nebo–Broadsound district in central Queensland. It describes a scheme to classify the grazing productivity of land types.
Soil research in the Middlemount area has shown that total nitrogen (%) and available phosphorus (ppm) levels in the surface soil explain much of the variation in grazing productivity seen within the district. Inherent levels of both soil nutrients reflect the interaction of climate, geology, topography, vegetation and fire history over time.
Soil levels of 0.08% for total nitrogen and 10 ppm for available phosphorus were the minimum critical levels measured on country used for fattening in the Nebo–Broadsound district. Land types with fertility levels below these cut offs are more suited to growing or breeding enterprises.