Size-dependent growth responses to competition and environment in Nothofagus menziesii

► We test effects of size, competition, and environment on Nothofagus menziesii growth. ► Only short trees are prone to shading so we separately model small and large trees. ► Stem diameter and light competition were main explanatory variables for small stems. ► Elevation was a main explanatory variable for large stems. ► Effects vary with size, competition controls growth in small trees, environment in large trees.