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The summers of 1994 and, to a lesser extent, 1998 were particularly dry in eastern Spain. As a result, several plant species were severely affected. We estimated drought-induced mortality in several populations of three pine species that co-exist in the study area (Pinus nigra, P. pinaster and P. sylvestris). Hydraulic conductivity, vulnerability to xylem embolism, and tree-ring width were also measured for each population. Results showed that mortality only affected P. sylvestris, and that there were significant differences between two populations of this species. Although maximum hydraulic conductivity and vulnerability to embolism were almost identical among species and populations, they differed in other aspects of their hydraulic architecture. In particular, (1) hydraulic conductivity per unit of leaf area was lower in the most acutely affected P. sylvestris population. Lower leaf specific conductivity causes higher water …