In Southern Switzerland two chestnut (Castanea saliva) sprout coppices (6 to 8 years old) were examined. The number of C. parasitica cankers increased from 411 (August 1990) to 722 (October 1992). In 1990 148 C.  parasitica strains were isolated from randomly chosen cankers. 54% of the isolates were assigned to the  normal (N) and 46% to the white (W) cultural type. Two years later the same cankers were sampled again.  80% yielded isolates with the same and 20% with a different cultural type. The portion of W isolates was   slightly increased by 2%.
C. parasitica was isolated from the cankers with the highest growth rate and from non-growing cankers. The  growing cankers yielded 43% isolates with the N cultural type and 48% with the W cultural type, whereas the non-growing cankers yielded 16% isolates with N and 42% with W cultural type.