The development of chestnut blight (Cryphonectria parasitica) was observed in a coppice stand of Castanea sativa in southern Switzerland, where hypovirulence has been present for more than 20 years. The stand was clearcut in 1984. Thirty-six sprout clusters with 440 sprouts were observed between 1990 and 1996. All the cankers were localized and measured. During the observation period, 163 sprouts (37%) were lost to mortality. As the dying sprouts were significantly thinner at breast height than the surviving sprouts their mortality is mainly attributed to competition. At the same time, however, chestnut blight incidence was high. Only 79 (28%) of the surviving sprouts remained blight free. The growth rate of the cankers was highest in their first year of appearance and then declined gradually. Hypovirulence had a strong effect. A total of 54% of the cankers were considered as healing on the basis that no reddish canker margin was visible. These healing cankers had a reduced growth rate compared to active cankers. Seventy-two percent of the healing cankers did not grow at all. No effect of the cankers on the increase in stem diameter could be observed.