Tree management is often discussed on USGA Course Consulting Service visits. Topics range from tree placement and species selection to overall health, just to name a few. A common sight at many golf courses is multi-trunk trees, also known as codominant stems. I often hear these referred to as “V trees” by golfers. While these trees sometimes act as an interesting reference point on the course, a codominant stem is a potentially dangerous situation. Some risks of codominant stems are:
Structural weakness: The point where trunks join can split, especially in high winds or heavy rain. This can cause large portions of a tree to fail suddenly.
Disease and pests: Weak points and cracks in the joint area can make a tree more susceptible to infections and infestations.
Maintenance challenges: Pruning and maintaining multi-trunk trees can be difficult and often requires professional help.
When someone asks a superintendent if a split is getting worse, it isn’t always easy to answer beyond what you think you see. I recently came across an easy method to see if, or how quickly, a codominant stem is splitting. This idea came from a golf course in Canada that is working with a certified arborist to identify trees for removal. The test doesn’t require anything more than a piece of wire and two rust-proof screws.
Bend the wire into the shape of a circle, passing the two ends over each other. Screw the two ends into the opposing stems of the split trunk and watch what happens. If the stems are diverging, slack will be taken up in the wire and the loop will become a straight piece. If you observe changes in the wire you can reach out to an expert for their recommendations or take action. This simple trick gives superintendents irrefutable evidence whether the split is in fact getting worse, which would make the tree a likely candidate for removal.
Northeast Region Agronomists:
Darin Bevard, senior director, Championship Agronomy – dbevard@usga.org
Elliott L. Dowling, regional director, East Region – edowling@usga.org
Brian Gietka, agronomist – bgietka@usga.org