Arborist hit when trunk did not fall as intended
A certified utility arborist was cutting a red alder school-marm (a tree that branched into two trunks). Supported with spurs and belts, he placed himself in the crotch of the school-marm, and cut each trunk approximately 13 feet from the ground. When the second trunk started to fall, it hit the branches of a maple tree. The falling trunk rotated; it then hit the branches of an alder tree and landed on a cedar tree. The butt end of the falling trunk turned towards the arborist and hit him, knocking him backwards and causing fatal injuries.
Findings as to causes
- A risk assessment was not conducted on the school-marm. A risk assessment should have considered the lean of the trunks, the direction of fall, other trees in the area, and the special request to cut the school-marm approximately 12 feet from the ground.
- A clear path for the falling trunk was not provided.
- Each trunk of the school-marm was cut down in one piece (approximately 60 feet) rather than in smaller pieces.
- The arborist was positioned in a high-hazard area, with no escape route. It was impossible for him to move out of the danger area after completing the backcut.
- Proper rigging equipment was not used to maintain control of the falling trunks.
Findings as to underlying factors
- The request that the school-marm be cut 12 feet from the ground meant that the trunks could not be cut from ground level, thus increasing the risk to the workers.
- The tree was felled in the direction opposite to the lean. This made it more difficult to control the fall of the two trunks.