Regeneration of Southern Rata (Metrosideros umbellata) and Kamahi (Weinmannia racemosa) in Areas of Dieback

Abstract

During the 1950s, dieback of southern rata (Metrosideros umbel/ata) and kamahi (Weinmannia racemosa) was documented in the conifer/ hardwood forests of the Kokatahi and Fox catchments in Westland, New Zealand. Thirty years later, southern rata was usually absent as a live tree in dieback stands. Kamahi, although absent from the canopy in the Kokatahi, had partially recovered at Fox, where it was still a dominant canopy species. Regeneration studies on a range of sites indicate that in the short term, kamahi and Quintinia acutifolia will become the structurally dominant canopy species in many of the dieback stands, and southern rata will at best be a minor component.