Improving Tree Structural Stability via Cabling


This is Big Bertha the fir tree. She lives south of Mt Horeb and was named by a tree loving 7-year-old. The mother of the boy called us and asked if we could stitch it back up after a summer storm. The possibility of cutting it down due to the split between the two halves was too much for the boy to manage and he pleaded with mom to call us.

The friendly guy at the bottom of the photo is Alex; he is standing in front of his handy work. He cleaned up the failed branch (see cut on trunk) and then took it upon himself to install the dynamic cables; you can see two cables there, installed as high as possible. These cables are more effective the higher up you put them in the tree.

Cables have a tensile strength of over 10,000 pounds making them very strong. The best feature of the support system is its stretch which allows the tree to move freely compared to rigid static steel cables. The other nice attribute of dynamic cables is there is no hardware installed or drilled into the tree. A simple knot is tied around the branch with room for future growth.

The one drawback to the dynamic cable is its lifespan. These cables need to be inspected every couple of years and replaced after 5-10 years due to potential wear and degradation over time. When compared to static cables the dynamic is a bit less expensive in the short term, but in the long run they would likely work out to be the same amount of investment depending on how long the tree remains on the property. 

Over the years, dynamic cabling has allowed us to prune suspect branches aggressively to reduce risk and then install the cable to provide a bit more insurance against branch failure. This is a tool that can help keep trees safely in the landscape longer. Long live Big Bertha!