| • Vulnerability to cavitation and conductive efficiency depend on xylem anatomy. We tested a large range of structure–function hypotheses, some for the first time, within a single genus to minimize phylogenetic ‘noise’ and maximize detection of functionally relevant variation. • This integrative study combined in-depth anatomical observations using light, scanning and transmission electron microscopy of seven Acer taxa, and compared these observations with empirical measures of xylem hydraulics. • Our results reveal a 2 MPa range in species’ mean cavitation pressure (MCP). MCP was strongly correlated with intervessel pit structure (membrane thickness and porosity, chamber depth), weakly correlated with pit number per vessel, and not related to pit area... |
