David Rowlings, 2 George Street, QLD , Queensland University of Technology, Brisbane, AUSTRALIA, Michael Bell, School of Agriculture and Food Sciences, University of Queensland, Gatton, Australia, David Lester, Department of Agriculture, Fisheries and Forestry, Queensland, Toowoomba, Australia, Clemens Scheer, Queensland University of Technology, Brisbane, Australia and Peter R Grace, Institute for Future Environments, Queensland University of Technology, Brisbane, Queensland, Australia