Woody plant restoration and natural regeneration in wet meadow at Coomonderry Swamp on the south coast of New South Wales

Abstract

This study investigated planting techniques and natural regeneration of indigenous woody species within degraded wet meadow wetland at Coomonderry Swamp. Planting tubestock directly into existing vegetation was practical and cost-effective. Clearing of plots allowed infiltration of weeds, early growth of tubestock was inhibited, acid sulfate soils were exposed, and open inundated plots were choked by algae. After four years, Melaleuca ericifolia and Melaleuca linariifolia showed good survivorship at upper and lower elevations. Eucalyptus robusta and Casuarina glauca were more successful at upper elevations, and Leptospermum juniperinum did not succeed at either elevation. These results corresponded to patterns of regeneration and to distributions within undisturbed stands. Despite the evidence of natural regeneration, direct seeding was not successful at the experimental site. Given that poor dispersal was indicated at Coomonderry Swamp, it is unlikely that isolated wetlands in the region could rely solely on seed dispersal for woody revegetation. Even where regeneration can occur naturally, some planting or culling might be required if the desired outcome is a species mix comparable to that observed on undisturbed margins.