Improving chronology for Aotearoa New Zealand: New research in tree-ring derived radiocarbon and stable isotope time series

Preserved Māori wooden artefacts (taonga (treasures)) in Aotearoa New Zealand (NZ), including house components, palisade posts, carvings and canoes provide valuable insights into the past. Understanding of the age of such objects can add value to their interpretation, determine their association with periods of social, environmental or cultural transition, and help inform future conservation and heritage protection. Empirical scientific methods such as radiocarbon dating are used to establish the calendar age of such objects. However, in NZ limitations on the accuracy of dates are imposed by radiocarbon calibration uncertainties during the last 800 years, coincident with the entirety of human occupation in NZ. Additionally, while elsewhere dendrochronology is commonly applied to archaeological wood, in NZ, this approach is hampered by species and growth ring characteristics. As a result, dendroarchaeology has been limited to dating kauri ( Agathis australis D. Don) wood from 19 th and early 20 th century contexts. Here we describe a long-term project employing tree-ring based 14 C calibration and stable isotope research that seeks to address these challenges and improve opportunities for the calendar-dating of archaeological sites and taonga in NZ.