The stand basal area, carbon isotope discrimination (D) intree rings and leaves, leaf area index and leaf traits of treeswere measured in 6- to 8-year-old stands ofEucalyptusglobulusLabill. across a gradient of rainfall of 600–1400 mm year-1in south-western Australia to better understandthe importance of leaf traits and gas-exchange asdeterminants of stand productivity.Dranged from 17‰ to21‰.Dand basal area were highly, positively correlatedwith each other and the ratio of mean annual rainfall topotential evaporation (P/PE). Leaf area index, soil waterholding capacity and leaf nitrogen content were onlyweakly correlated with basal area.DandP/PEwere negativelycorrelated with leaf nitrogen content.Dwas negativelycorrelated with leaf density but positively correlatedwith specific leaf area. This is consistent with the theory thatlarger leaf nitrogen content and smaller specific leaf areaare associated with increased photosynthetic capacity andincreased leaf-scale water-use-efficiency, and thatDis influencedby mesophyll conductance. It is concluded that canopyconductance is a more important determinant ofgrowth in water-limited conditions than either leaf areaindex or leaf traits in fertilized stands ofE. globulus. Wateravailability was dictated more by rainfall than soil type.