To disintegrate pruned branches and leaves into pieces of as uniform sizes as possible by placing a receiving blade supporting the pruned branches and leaves at the downstream of a pinch roller, and to reduce the load in the course of disintegrating the pruned branches and leaves by placing a blade supporting the pruned branches and leaves at the downstream of a pinch roller.

A disintegrator of the pruned branches and leaves is constituted of a pair of upper and lower rollers (pinch rollers) 36, 37 feeding the pruned branches and leaves at a predetermined speed while pinching them, the receiving blade 39 supporting the pruned branches and leaves by being placed at the downstream of these upper and lower rollers 36, 37, a plurality of hammers, 38, etc. disintegrating the pruned branches and leaves into small pieces by knocking down the pruned branches and leaves protruding from the receiving blade 39, a rotary drum 47 supporting rotatably these hammers 38, etc., and a housing 42 totally covering these upper and lower rollers 36, 37, the receiving blade 39, the hammers 38, etc., and the rotary drum 47.