Changes in the vegetation of the river red gum forest at Barmah, Victoria

Summary Changes in the vegetation of Barmah State Forest, situated on the floodplain of the River Murray in northern Victoria and dominated by river red gum (Eucalyptus camaldulensis), have been deduced by examination of historical and recent evidence. The factors influencing vegetation changes have been (1) a reduction in frequency of burning following the displacement of aboriginal tribes from the area, (2) intense grazing by rabbits from the 1880s until their control by myxomatosis, (3) grazing by domestic stock, and (4) the effect of river regulation including less frequent winter/spring flooding and the entry of water into the forest during summer as a result of high river levels managed for crop irrigation purposes. In addition to the described effects on the health of trees, the area of grassland has been reduced significantly. Extensive areas previously dominated by Moira grass, common reed and/or cumbungi are now covered with red gum forest or beds of giant rush.