What can be Done About Bark Inclusions

Homeowners should look for these signs:

1) Trees that have target significance to structures, roads, or anywhere human may place themselves or their valuables (cars, tools, machinery, etc.). This means that if a tree were to fall, what might it hit?

2) Trees that begin with a single trunk, become co-dominant (2 or more trunk), and have a narrow angle of attachment.

3) Multi-stemmed trees with narrow or wide angles of attachment that are retaining water/or have several inches of soil buildup in the unions.

4) Trees with heavy or sudden leans, as this may be a sign of a weakening union.


In respect to bark inclusion, homeowners should avoid the following:

1) Topping/heading trees (especially fast-growers like eucalyptus, acacia, locust, maple, alder, and sycamore) unless they are maintained yearly. This is expensive and not cost effective. I hesitate even to admit that last statement, but I have seen many cared-for wind rows and noise screens. Topping is never a suitable practice, and has many negative ramifications such as dramatically increasing the risk of bark inclusion and stem failure. See the “should I top my tree” article in the educate section for more information.

2) Using your gardener to inspect your trees. Gardeners are not trained tree professionals. They do not understand tree disease and tree hazards and tend to overestimate or underestimate risk potential. Furthermore, they often utilize trimming practices that increase the risk of decay, disease, and hazard potential. See our “hack of the month” section from our homepage for some trees worked by gardeners.

3) Hiring tree trimmers that cannot demonstrate education in the field or do not have examples/references for their work. While it is safer for a homeowner to hire an arborist, there are also many educated and reputable tree trimming professionals in our area. Arborists, unlike tree trimmers, have to work by a code of ethics that they are held up to by their colleagues and by the International Society of Arboriculture (ISA). They have to consistently educate themselves in order to keep the certification. Unfortunately, there are many trimmers in the Santa Cruz area that will pretend to be Certified Arborists to increase their chances of getting work. If the individual says he/she is an arborist, ask to see some identification. All arborists carry a laminated card from the ISA. For a list of arborists in your area, or to weed out who is not an arborist, click here to visit site.

4) Hiring someone other than an arborist do the cabling/bracing work on your trees. Arborists are specifically trained on these two areas of tree care.

***** In conclusion, an alert and watchful homeowner can help minimize or eliminate the damage that their trees cause. The benefits from trees are many, and outweigh the risks of having them around. Properly cared for trees have little risk. Take some time every year to evaluate your trees, considering the bulleted points in this article. If you have questions, call an arborist for a consultation. Most importantly, if you have trees with hazard significance, have an arborist do a site evaluation yearly to protect your investment.

Craig Erickson- owner
Koala Tree Care