The thesis describes the integration of a hydraulic chainsaw with a grapple. We worked on developing the attaching plate and hydraulic connection of a chainsaw with a grapple. The goal was to develop an attaching plate that will allow a simple connection of chainsaw with a grapple. The hydraulic circuit was modified in order to minimize the changes of the existing hydraulic installation on the grapple and work without the additional directional control valves on a mobile heavy equipment. Furthermore, the rigidity of the attaching plate was checked using a finite elements method and a Siemens software NX Nastran. We also measured hydraulic parameters both in a laboratory and on a mobile heavy equipment.