Quite regularly I encounter trees that are being girdled by some sort of material, mostly guy wires or straps installed during planting, and subsequently forgotten. Sometimes there are other things that catch me by surprise. Usually these are things placed by people and never maintained. For this article I will start with the most common girdling issue and then mention some of the other items.
Illustration of a tree being girdled by a guy wire. ©Russell Tree Experts
Support Systems
There are various methods in use for supporting newly planted trees. From nylon webbing straps to wire run through hose, or just plain wire, it seems folks will reach for what is at hand to tie around a tree stem after planting to help support a tree. For this article I am not going to discuss proper guying methods. The most important thing to remember is that whatever guying system you, or someone else, has installed on your newly planted tree(s), the system should be checked periodically to make sure it is still functional without causing damage to the tree stem. Usually one season is all that is required for a tree support system installed at planting. Sometimes guying is not needed. This largely depends on whether the new tree is planted bare root or balled and burlapped.
At any rate, several times I have been called to investigate a strange phenomenon: A tree looks healthy in the lower part of the canopy, but the upper part is turning yellow and dying. On closer inspection, I will find the remains of a guy wire (or two, or three) buried into the tree stem, clearly marking the boundary between healthy tree below and strangled tree above. If I can remove the material the recovery of the tree is quite dramatic. If the material is too buried to be reached, tree survival is a question of whether the tree is able to bridge over the girdling with new stem growth or not. In rarer cases I have seen trees snap off at the place where a guy wire was buried in the stem causing a structural weakness.
I see this type of injury far more often than I would like, and far too often considering how easy it is to loosen a guy wire that is still needed or remove it if it has fulfilled its function. For support systems that need to be permanent, bolts drilled into the tree are a preferable option since the tree can easily grow around the bolt indefinitely.
Other Stem Girdling Culprits
The following list is made up of other things I have seen noticeably girdling tree trunks or branches, sometimes with negative effects on tree health:
Bird feeder hooks
Swings attached with rope, wire, or chain
Nylon twine on a root ball left in place after planting
Zip lines
Christmas lights installed and never removed
Ribbon
Tree identification tags attached at the nursery
Pictured above is an Emerald Green Arborvitae that is being girdled by a fabric ribbon used to help promote proper growth of the tree when it was much younger.
Some of these might come as a surprise since one would think that the material would degrade quickly and not cause a girdling problem. With ribbon in particular, I have seen ribbon so old the color has faded away, yet there is a noticeable groove in the trunk where the tree is beginning to be girdled. When I cut the ribbon with my knife it gives way with an audible tearing or snapping sound, showing there is still a lot of strength left in it. Granted, the ribbon might actually decompose before the tree begins to suffer irreparable damage, but I left it on my list simply to illustrate that anything attached to a tree should be maintained or removed if its purpose is fulfilled.
Trees lend themselves for usefulness, decoration, and personal expression. Sometimes trees need to be supported for a time, or indefinitely. Take a walk outside and look at your trees. Is there any girdling going on? Is it time to replace or remove a guy wire? Should you use a larger hook for your bird feeder? Is there burlap or twine strangling the base of the tree? Make the adjustments! Believe me, every little thing you can do in favor of the tree counts.
Thanks for caring about your trees!
PS - Read Chris’ great article about girdling roots by clicking here!
José Fernández | Regional Manager, Russell Tree Experts
José became an ISA Certified Arborist® in 2004, and a Board-Certified Master Arborist® in 2015. Currently he is enrolled at The Ohio State University pursuing a Master’s Degree in Plant Health Management. José likes working around trees because he is still filled with wonder every time he walks in the woods. José has worked at Russell Tree Experts since 2012.