A review of the published literature suggested that plants with a clonal growth habit dominated the
vegetation of wetlands in many parts of the world. To test whether this pattern held in Australia, the
distribution of plants with clonal and non-clonal growth habits was examined in Clydebank Morass,
a brackish-water wetland of the Gippsland Lakes in south-eastern Victoria. Nineteen of the twenty
species of aquatic or semi-aquatic plants present in the wetland were clonal. In terms of both species
number and percentage cover, clonal plants dominated the vegetation in wet and intermittently damp
parts of the Morass whereas non-clonal plants were progressively more common as elevations
increased. This elevational effect was due more to changes in soil moisture content than in soil salinity.
These results not only confirmed the prediction that clonal plants were the dominant growth
habit in the wetland but were consistent with predictions made in the 1960s as to likely vegetation
changes as the Gippsland Lakes became progressively salinised. Understanding the dominance of
wetlands by clonal plants has implications for assessments of plant fitness and the maintenance of
plant biodiversity and habitat heterogeneity; it is central also to improving the success with which
degraded wetlands are rehabilitated.