Composition and Classification of Nothofagus moorei Communities in Northern New South Wales

Abstract

Nothofagus moorei (F. Muell.) Krasser occurs disjunctly in northern New South Wales from the Barrington Tops area to just beyond the New South Wales–Queensland Border. The main centres of occurrence are areas within the Barrington Tops–Gloucester Tops, the Upper Hastings, the escarpment of the Ebor–Dorrigo Plateau, and the Border Ranges–Lamington Plateau (McPherson Range). Minor but significant stands of N. moorei occur on the Comboyne Plateau, the East Dorrigo area, and in the western McPherson Range. Throughout this range, site characteristics vary considerably, both in landscape morphology and in parent material type. The altitudinal range of N. moorei is 1000 m. Such site variability makes the disjunctness of N. moorei more problematic.

The floristic composition of these communities was investigated at 60 sites scattered throughout the geographic range. More than 400 species of vascular plants were found to occur with N. moorei, including at least 50 species of climbers and more than 40 species of epiphytes and lithophytes. Around half of this floristic richness may be attributable to mixed assemblages of cool temperate and cool subtropical species, particularly at low altitude sites and rather fertile mid altitude sites. Nevertheless, it is clear there is a distinctive temperate floristic group which characterises the principal domains of N. moorei.

Floristic analyses based on ordination techniques produced site clusters which at a coarse level matched the disjunct geographic domains of N. moorei. Locally, topographic gradients, geological factors, and site histories contribute to floristic dissimilarities. There is little evidence of widespread species assemblages of high fidelity. Nevertheless, some species co-occur commonly enough to offer some support to intuitive floristic classifications.