Maybe you’ve heard that the number of rings a tree has is how old the tree is, but what else can tree rings tell us about trees? This short post gives a breakdown of tree bark and tree rings. Besides age of trees, we can also learn about climate, weather, diseases or invasive species and more.
The age of a tree is called diameter growth. It is a combination of the light and dark rings in a tree, amounting to 1 year of growth. The lighter part of the diameter growth is wider than the dark ring. Most of the tree growth within a single year happens in the spring and summer, where the lighter ring comes from. When growth begins to slow at the end of summer, the ring darkens and is called “summerwood” or “latewood.”
*Fun fact: In tropical climates where there are not distinct weather changes with four seasons, the annual rings are harder to see. Age is harder to tell.
Trees grow in two directions- they grow upward and outward. The rings on trees are often narrower on trees that grow slowly through the year. Oak trees for example have a longer, slower annual height and width growth span. This means that the rings are often narrower and closer together. Trees like willows that have a quicker growth rate also have rings that are wider.
Changes in the climate and environment such as infestations of disease or invasive species impacts the tree rings as well. Narrow rings could mean the year was dryer (less rainfall) or that there was a forest fire nearby. Lack of sun could also be an issue for a tree and the rings will be narrower. Trees will often overcome environmental factors and bounce back when conditions are at their optimum. Rings will be wider as growth improves.
There are other things you can tell about a tree from its rings such as if it grew at an angle or leaned on another tree, if the wind was strong on one side of the tree vs the other, and if there were heavy branches that made waves in the rings at any point.
Tree rings tell a story of a tree’s life, and it’s awesome that we can pick out key moments for the tree and what it went through different years and stages of its growth.
What’s something that you learned about trees and their rings? Comment below!
And remember, you can always contact our team at Cutting Edge Tree Professionals by email at firstname.lastname@example.org or by calling us at 814-201-9757.