Wood density
We determined wood density for each stem used for hydraulic and vascular anatomy measurements (n=160), by calculating the volume of the stem sample (~2cm in length per sample) by the method of water displacement (Osazuwa-Peters & Zanne, 2010), then we dried the sample in an oven for 48 h at 60 °C. Thus, we determined wood density (g cm-3) as the dry mass divided by the volume of wood.