Ecology of Dracophyllum subulatum-dominant heathland on frost flats at Rangitaiki and north Pureora, central North Island, New Zealand

Abstract

Abstract The structure, composition, and dynamics of heathland dominated by Dracophyllum subulatum (monoao) on “frost flats” (plateaus and shallow basins supporting low vegetation and subject to year-round frosts) at proposed Te Papa Ecological Area, Rangitaiki and Waipapa Ecological Area, Pureora, were investigated. Systematic sampling and subsequent classification identified five frost flat and related communities at Rangitaiki, the three minor ones apparently occupying moister sites of varying drainage and fertility; one frost flat and one related community had previously been identified at Pureora. The floristic affinities of frost flat heathland lie with the largely fire-induced tussock grasslands of eastern South Island; most of the ubiquitous species have wide ecological amplitudes and several of them are important early colonisers elsewhere in New Zealand. Mean annual diameter growth rates of monoao in the major communities at both localities ranged from 0.5 to 1.2mm yr−1; mean annual height growt...