The shaking and catching devices of a mechanical harvester damaged the young vegetative canes of raspberries. The consequences of this damage were assessed in the following year when these canes fruited. Yields were reduced by up to 38%, the extent of the depression varying with the number of passes of the machine in the previous year. There was little difference between 4 cvs in the degree of yield loss. Yield depression was attributable both to death of a proportion of the canes and to reduction in the number and vigour of buds developing on the surviving canes.