Cabling a Tree
How to prevent ice and storms from breaking one trunk off a double-trunk tree
I have an old, 35-foot-tall Eastern red cedar with a double trunk. I'm afraid an ice storm will eventually break off one of the trunks. Would cabling prevent this?
Robert Baden, Palmyra, VA.
Roger Cook replies: There's no guarantee that a weak crotch won't split, although cabling will definitely help. But you can stack the odds in your favor by hiring a certified arborist to do the work. This is not a do-it-yourself project.
Once an arborist determines the right height for one or two cables, he'll climb the tree and drill a hole through each main branch and insert a threaded, galvanized eyebolt that is held in place with a large washer and two nuts. The two eyes are connected using steel cable. To keep the trunk from splitting, he may also drill crisscrossing holes through the trunk for threaded rods.
The tree will eventually grow over and hide the rods, but it can't be allowed to cover the eyebolts, which have to be inspected, and perhaps adjusted, every year or two as the trunks grow. An overgrown cable-eye connection may lose its ability to move with the tree and cause the cable to snap.