Written by Greg Drecher, ISA Certified Arborist #PD-2775A
Most homeowners never think about tree cabling until someone points it out to them. During a recent property assessment in Berwyn, PA, that’s exactly what happened, twice, on the same property, for two different reasons.
One tree had never been cabled at all. The other had a cable already in place, installed years earlier, that had quietly reached the end of its useful life. Seeing both side by side is a good way to understand what cabling actually does, and why it isn’t a one-time fix.
The Pin Oak With No Cable at All
The first tree was a pin oak on the left side of the backyard, growing with a dual union, meaning the trunk splits into two major stems fairly low down instead of one central leader. This is a common growth pattern, not a defect on its own, but it creates a structural weak point. Where two stems meet at a narrow angle, the wood never fully fuses the way a single trunk would. Under the right conditions, high wind, heavy wet snow, or just the accumulated weight of years of growth, that union can fail.
This pin oak had never had a cable installed. As part of the assessment, Greg recommended adding one, a flexible support cable installed high in the canopy that limits how far the two stems can move independently of each other. It doesn’t stop the tree from swaying in wind, which it needs to do, it just keeps the two halves from separating past a safe point.
The Tulip Poplar’s Cable Had Already Done Its Job
A few yards away, a dual-trunk tulip poplar told a different story. This tree already had a cable installed from a previous job, but it was old enough that Greg recommended replacing it rather than leaving it in place.
Cables aren’t permanent. Hardware corrodes, trees grow around old anchor points, and a cable installed a decade or more ago may no longer be rated for what the tree needs today. A tulip poplar is a fast grower, which means the gap between “correctly sized cable” and “outgrown cable” closes faster than most homeowners would expect. Replacing an aging cable is a normal part of tree care, not a sign that the first installation failed.
This particular install was done as a manual climb rather than from a bucket truck, working from inside the canopy to reach the exact point where the cable needed to sit. That’s the kind of access decision an ISA Certified Arborist makes on site, not something that gets planned from the ground.
What a Cabling Assessment Actually Involves
The International Society of Arboriculture lists cabling and bracing among the standard tools a trained arborist uses to support structurally weak trees, not a substitute for good pruning, but one more way to extend a tree’s safe life when the structure calls for it.
Both trees were part of the same walkthrough, and the process looked the same for each:
- Check the union or trunk split for early signs of stress, cracking, or included bark
- Determine whether a cable is present, and if so, inspect the hardware and cable condition
- Decide on cable placement height and tension based on the tree’s size and growth pattern
- Install or replace the cable using rigging anchored directly into the trunk
- Document the work with photos for the property record
This same visit also covered canopy clean-up, deadwood removal, and clearance pruning elsewhere on the property, standard work for a mature landscape. The cabling was the part worth highlighting here because it’s the piece most homeowners don’t know to ask about. If you’re not sure whether a tree on your property could benefit from cabling or bracing, that’s exactly the kind of thing worth asking about during a routine assessment.
Why This Matters Before Storm Season
Pennsylvania’s late summer and early fall bring the highest risk of the year for tree failure, remnant tropical systems, sudden downpours, and wind events that catch soft, saturated ground off guard. A tree with a structural weak point, whether uncabled or under-supported by aging hardware, is more likely to fail under exactly those conditions.
The point isn’t that every tree needs a cable. Most don’t. But a tree with a visible dual union or an existing cable that hasn’t been inspected in years is worth a second look before storm season, not after.
Not every cabling situation looks like the two trees here. If your tree is already leaning rather than simply uncabled, that’s a related but different diagnosis, read more about what cabling can and can’t do for a leaning tree. And if you want the broader picture on why cabling helps in the first place, the general benefits of tree cabling and bracing are covered there.
Get an Assessment Before the Next Storm
If you have a tree on your property with a split trunk, a dual union, or a cable you can’t remember the age of, it’s worth having someone take a look. Ready to have an ISA Certified Arborist take a look? Schedule your free estimate today.