Natural history of the Hogan Group - 3. Floristics and plant communities

Abstract

A total of 146 vascular species were collected on the Hogan Group in January 1968. The composition of the flora is broadly similar to other islands of Bass Strait, and the coastal areas of Victoria , Tasmania and eastern South Australia. The vegetation may be classified into six structural forms and ten associations. The most extensive communities are Poa poiformis tussock grassland, Helichrysum paralium shrubland complex, Disphyma austral-Carpobrotus rossii succulent herbfiled, and Lolium perenne continuous grassland. Analysis of a fossil pollen profile from Hogan Island indicates that there has been no drastic change in native species composition over the last 150 years, although there is evidence that shrub species of the Compositae have been reduced in importance. Recent evidence shows that burning and grazing have resulted in a reduction in shrubland area, and the modification or removal of Poa poiformis tussock grassland.