When wounds on raspberry canes caused by machine harvesting in the previous year were infected by L. coniothyrium the potential yield/cane was reduced by 45% compared with that of uninfected hand harvested canes. However, the corresponding reduction/plot was less (about 25%) because the yield of wounded but uninfected canes was not reduced and some canes were not wounded. The advantages and disadvantages of recording potential yield/cane are discussed.