The man had been working on steep ground within the forest when a previously felled tree started to move. The tree struck the worker causing serious injuries which included facial damage and suspected breaks to an arm and leg.
The Welsh Ambulance Service and the Welsh Air Ambulance also attended the incident but, owing to the difficult terrain, were unable to extract the casualty. The mountain rescue teams and paramedics were assisted by a SeaKing from RAF Valley who successfully winched the man up from the hillside and transported him to Ysbyty Gwynedd.