Abstract
The effect of mass mortality of oak trees, caused by the fungus Raffaelea quercivora, on the stand structure of a broadleaved secondary forest was investigated in a stand located in northern Kyoto City, in mid-western Japan. In the study stand after the epidemic, Ilex pedunculosa was the dominant species (basal area), followed by Fagus japonica, Quercus crispula, Acanthopanax sciadophylloides, and Magnolia salicifolia. More than half the Q. crispula individuals died during the epidemic. The number of dead Q. crispula trees suggested that the species would have been dominant in the tree layer before the epidemic. Individuals closer to the epidemic source and larger individuals suffered the highest mortality. M. salicifolia, A. sciadophylloides, and F. japonica had many stems expected to regenerate in the gaps resulting from death of Q. crispula trees, and these species are predicted to become more dominant in the tree layer at least in the short term. Hamamelis japonica var. obtusata and I. pedunculosa are also predicted to become more dominant in the middle and shrub layers.
