Cabling is most often used to support a tree canopy that has a structural defect, such as a crack. With the higher branches moving in the wind, you get significant leverage on the crack, making it worse. Cabling stops the leverage by securing the upper branches. You want to go two thirds above the defect to put in the support system in one of several patterns.
There are three basic kinds of tree “orthopedics”:
• Cabling- this is up in canopy of a mature tree. It can involve one or multiple applications.
• Guying- this is used on a healthy tree whose roots are not holding.
• Bracing- threaded rod is put through the wood of the defective part to hold a split together.