Bend-and-Swing Rigging

OK, here’s what we had to do: Remove two bent birch trees (leaders) that were overhanging a beach. We couldn’t just drop them into the lake, because we had no way to fish them out of the water. They would be partially submerged and ridiculously heavy underwater, and they were already full-length leaders weighing close to, well, let’s just say a lot. We didn’t have access to get a loader or truck in there, and we had nowhere to drag them if we did manage to get them out of the water. So we had to get creative. (Photo 1)

Photo 1: The two leaders overhanging the water. All photos by Tchukki Andersen.

The plan was to remove each of the two leaders in one piece. First the smaller leader, then the bigger one, by “bending” them at the base and then “swinging” them over to the shore. I selected a sturdy oak tree just up the shore to act as a gin pole. I ran a ½-inch, double-braid rigging rope through a block, climbed up about 35 feet and secured the block with a cow hitch. This rigging point was going to act as the rigging redirect and would have to endure a lot of side-load pressure as we cranked the two trees over to the beach. We attached our dependable Hobbs H2 lowering device at the base to take up the slack in the line and eventually lift the weight of the trees. (Photo 2)

Photo 2: Here we see the Hobbs H2 with the bollard filled with wraps to hold the weight of the leaders.

To tie the rigging line to the first tree, we shot a throwline out over the approximate center of gravity of the tree. Our ground operator had to do some fierce, in-boot toe gripping to avoid falling in the water as he retrieved the running end. (Photo 3)

Photo 3: The retrieve-the-throwline moment.

The rigging line was tied to the throwline and anchored on the leaning trunk with a running bowline. The first leader was much smaller and lighter than the second, so it was a good practice run for our bend-and-swing plan.

I made a notch at the base angled toward the gin-pole tree up the shore and cranked up the Hobbs to basically hold the entire weight of the small leader. Then I made a series of shallow back cuts to get the tree to start bending. The crew members cranked up the Hobbs one notch at a time as I made the shallow cuts and the tree swung over to the beach. We relied on all that hinge fiber to hold the weight of the tree and bend it toward the shore. It worked great, so we were feeling better about pulling over the larger leader. (Photo 4)

Photo 4: Cranking out the small leader.

We installed the rigging line in the canopy of the larger leader and reviewed the plan again. This time, the cuts at the base were more critical. We made a shallow face cut on the side toward the direction of pull. The idea was to leave a giant section of hinge wood – 3 to 4 inches – and use the strength of the fibers to bend the tree against the 3- to 4-inch hinge. The crew members cranked on the Hobbs, and the tree started to bend against the face cut. The hope was that the hefty hinge would not break at any point while the tree was over water and cause a boatload of additional problems. So we added a Port-a-Wrap lowering device just below the face cut and attached a separate tag line to keep the butt end from swinging out into the water when it was released. (Photo 5)

Photo 5: The 3-inch hinge in the larger leader.

The crew continued to crank on the Hobbs, pulling the tree over and closing the face cut. That giant hinge held! When the tree was parallel to the shore, I cautiously made some shallow back cuts to slowly release the fiber tension. I left just enough fiber so when the tree was lowered, the butt would not roll off into the water. (Photo 6)

Photo 6: The release cuts on the larger leader.

The crew members reversed the Hobbs and lowered the second birch leader to the ground. It worked. Everything went according to plan! I think the key to this being a successful operation was that we took everything very slowly and evaluated every step. We didn’t get greedy with our saw cuts, which was especially important when I made the release cuts. Now all we had to do was cut it all up and haul it out of there. (Photos 7 & 8)

Photo 7: Using the Hobbs to bend the second leader over.
Photo 8: It’s on the shore.

Chris Girard is a Certified Treecare Safety Professional (CTSP), a Certified Arborist, a Society of Professional Rope Access Technicians (SPRAT) Level 1 Technician and owner of Girard Tree Service, a 12-year TCIA member company based in Gilmanton, New Hampshire.

Tchukki Andersen, CTSP and Board Certified Master Arborist (BCMA), is staff arborist for the Tree Care Industry Association and author of TCIA’s revised and soon-to-be-released “Best Practices for Rigging in Arboriculture” manual.

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