Maryland Grows

Q:  There’s a crapemyrtle in our new yard that has a plastic cable tying it to a stake that has become stuck in the wood. Should I cut it out so the trunk can heal?

A:  No, that will cause more damage and potentially lead to even more wood decay and crown dieback. All you can do is carefully cut off the excess outside the bark (don’t worry about making it flush; you don’t want to cut into live wood). Gardeners and landscapers should monitor any trees they stake for indications a trunk tie is abrading, cutting into, or being enveloped by the bark. Most trees don’t need staking, and even when they benefit from it, removal of the stakes and ties is recommended after six to twelve months of use. No tie or trunk brace should be so tight that the trunk cannot sway a bit in the wind.

It’s hard to predict how much of an impact the damage you found will have on the branches that particular trunk feeds. Fortunately, the tie in your case did not encircle the trunk, just brace one side of it; I’ve seen several instances where encircling ties become embedded and essentially strangle and kill the entire top of the tree (Leyland cypress and Arborvitae being common victims).

Tree and shrub wood expands outwards as it grows, increasing in diameter as each ring of new wood growth is formed yearly. Although an imperfect comparison, there are parallels to how coral reef colonies grow – over time, the innermost “skeleton” is no longer alive, though it provides support, and the outer shell of tissues is living and actively growing, save for the bark itself. (You can think of bark a bit like nails on a person or pet…it’s produced by live tissue, but the material itself is not alive.)

If the tie extensively obstructs the cambium that lies under the bark (the live tissues moving water, sugars, and nutrients around the tree), one or more major branches above it may die back in the coming years, for which there is no treatment. In some cases, the obstruction just becomes buried under years of growth, hiding it from view. (This is a hazardous situation if the tie or obstructing material were metal, and the tree was removed and chipped up one day.)

Trees can’t heal quite the way animals do, but with luck, this damage will remain minor and not cause significant dieback. If it does, though, you’ll have to cut down that trunk. Since crapemyrtle tends to sucker readily, new growth can take its place if you let a sucker mature into another trunk.

By Miri Talabac, Horticulturist, University of Maryland Extension Home & Garden Information Center. Miri writes the Garden Q&A for The Baltimore Sun and Washington Gardener Magazine. Read more by Miri.

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