Eucalyptus rudis Endl. saplings were exposed to either 274 μg m−3 SO2 or 132 μg m−3 SO2 for 8 h d−1, over 123 d, in open-top chambers. Exposure to 132μg m−3 SO2 increased the height of the plants and increased the average area and dry weight of leaves. Exposure to 274 μg m−3 SO2 increased the concentration of total sulphur in the leaves and increased the number of leaves abscised. Sulphur accumulation in the leaves decreased as the duration of exposure increased.