Magnitude of Canopy Dieback and Implications for Conservation of Southern Rata-Kamahi (Metrosideros umbellata—Weinmannia racemosa) Forests, Central Westland, New Zealand
The amount of conspicuous canopy dieback in all central Westland southern rata-kamahi forests east of the Alpine Fault, between 500 m altitude and treeline, was assessed and mapped from aerial photographs taken in 1984-85 and verified by aerial reconnaissance of selected areas in 1988. At least 20% of all canopy trees, predominantly southern rata (Metrosideros umbellata) and Hall's totara (Podocarpus hallii), were dead in 1984-85.