Strictly speaking, tree rings referred to the concentric ring patterns on the cross-section of woody perennial stems, and they were common in trees and shrubs. Usually, each ring represented one year.
The boundaries varied from region to region. In places with a temperate climate, the tree rings were obvious. However, in areas with a tropical climate, the rings were not too obvious because of the weather did not change too drastically, but they could still be identified.
In cold regions, the tree rings were much more visible.
