Whole-tree winter leaf-loss in wineberry (Aristotelia serrata, Elaeocarpaceae) is not related to mean air temperature

Winter leaf-loss of wineberry (Aristotelia serrata) was measured at a range of sites in the South Island of New Zealand in early spring to investigate the temperature dependence of deciduousness in this species. The number of leaves emerged over the growing season on both shaded and exposed shoots i ncreased with temperature across sites. There was consistently greater leaf loss from exposed shoots than from shaded shoots. Contrary to a widely hel d view, there was no temperature dependence of leaf loss in wineberry at th e whole-tree scale. However, the difference in proportional leaf loss betwe en exposed and shaded shoots decreased with increasing temperature, driven by an increase in leaf loss from shaded shoots at warm sites. Causes of the se patterns may be elucidated by investigations of shoot-level phenology an d leaf responses to winter photoinhibition.