Management of kauri dieback

Abstract

Kauri illthrift commonly known as Kauri dieback has been identified as an increasing problem affecting kauri (Agathis australis) across the Auckland region A water and soilborne pathogen Phytophthora taxon Agathis (PTA) has been identified as a causal agent of Kauri dieback at some locations particularly within the Waitakeres Ranges Regional Park and Great Barrier Island PTA is associated with a collar rot causing large bleeding basal lesions yellowing foliage and tree death A range of other causal agents including Phytophthora cinnamomi and environmental stress factors were also associated with symptoms at many sites In 2008 Auckland Regional Council implemented a range of standard operational procedures to manage the disease across the region Surveillance surveys are underway to assess overall tree health as well as the potential distribution of PTA in Aucklands kauri forests Survey sites were prioritised in areas with high conservation value iconic trees or high levels of soil disturbance such as tracks intersecting kauri root zones Risk management of the suspected primary vectors of the PTA including people and feral pigs is underway