Reconnaissance survey of a glaucous eucalypt near Louisa Bay, southwestern Tasmania

Abstract

Stands of a glaucous eucalypt in the vicinity of Louisa Bay, southwestern Tasmania, which has affinities to Eucalyptus tenuiramis (Series Piperitae), were surveyed in order to determine their taxonomic status and record aspects of their population ecology. Two main populations were observed in scattered stands among predominantly moorland vegetation at the Red Point Hills and Louisa Plains. One stand from each population was accessed for detailed study. Contiguous plots located along transects across the copses were used to record changes in population status, floristics and site conditions. Individuals of the glaucous eucalypt were small in stature and frequently malleeform near the moorland boundary, but were taller (10-12 m) and straight with single, slender main stems toward the centre of the copse. The Red Point Hills stand comprised a larger number of smaller individuals than the Louisa Plains stand and had been subject to at least three fires in the last 65 years, whereas only one fire had occurred on the Louisa Plains in the same period. These observations have implications for fire management: an appropriate regime, which encourages regeneration around the stand margins rather than increasing the edge-effects, needs to be devised. Given the geographic discontinuity with Eucalyptus tenuiramis, the southwestern copses may represent a relict dry sclerophyll community that was once contiguous with eastern Tasmania during the height of the last glaciation.