Key takeaways
- One light and one dark band make a year of growth
- Wide rings mean good growing years and narrow rings mean stress
- You can estimate age from trunk size without cutting the tree
- Growth rates differ by species, so estimates are only a guide
How rings form
In spring, trees grow fast and make light, wide wood. In late summer, growth slows and the wood is dark and dense. Together they make one ring.
Wet years leave wide rings, and drought years leave narrow ones. A cross-section is a record of the weather.
Counting rings
On a cut stump, count rings from the center outward. Tight, hard-to-see rings near the edge may need a magnifier or a sanded surface.
A core sample, taken with a small hollow drill called an increment borer, lets arborists count rings without hurting the tree.
Estimating a living tree's age
Measure the trunk circumference at chest height, divide by pi to get the diameter and multiply by a growth factor for the species. Fast-growing trees have a low factor and slow growers a high one.
It is only an estimate, but it is close enough for most uses. Our Ring Reader does the math for you.
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Quick answers
Do tree rings always equal years?
In most Tennessee trees, yes, one ring per year. Stress can cause false rings or missing rings.
Can I count rings on a standing tree?
Only with a core sample. An estimate from trunk size is easier.
Ready to talk it through? Get a free estimate or call 615-431-3789.