Abstract
A wide-range a.c. bridge was used to assess injury and mortality in E. obliqua seedlings following heat stress. The impedance ratio of the lower stem was correlated with other methods of assessing injury such as the degree of defoliation and the capacity for subsequent growth. Seedlings were also decapitated and the extent of injury was compared with heat-stressed plants. It seems that the effect of decapitation is a major component of the injury caused by heat stress.