Tree Age

Trees tell us so much: their species, the conditions they require for growth, and their age, among other things. The age of a tree is important in order to understand how any given tree benefits us and what we can do to prolong its life. 

Age Estimation for a Standing Tree

Determining the age of a tree once it has been cut is fairly simple, but what if it’s still standing? Although approximating can be difficult, it can be done.

First, the circumference of the tree must be recorded. This can be done with a measuring tape, starting about 4.5 feet up the tree. Measuring a few feet from the ground is important so that diameter at breast height is established and mature. Once the circumference is taken, the next step is to calculate both the diameter and the radius. Since we know that the equation to calculate the circumference of a circle is C=2πr, where pi, at 3.14, is multiplied by the radius, we simply restructure the equation to find the diameter. Divide the circumference by 3.14 to get the diameter, and further divide that by two to get the radius. Once the radius is established, it’s important to deduct 2 inches to account for the average bark thickness.

Next, growth factor is considered. In this step, species of the tree at hand is important as the vesicular structure of trunk pores vary from species to species. Growth factor tables can be found online and in tree guide books based on the average found for a particular species. For instance, a Black Walnut’s growth factor is 4.5. Once the growth factor is determined, it is multiplied by the diameter from the previous step. That value can be interpreted as an estimated age of the tree. 

Age Estimation for a Cut Tree

Once a tree is cut down, approximating age is much simpler. Starting from the center, count the dark rings - and this tells you the age of the tree! By studying the rings, you can learn about what the tree has endured over its life. For instance, insect invasion, intrusion by another force, fire, and other natural elements can be evaluated by the rings within the tree.

Tree Age / Size and the Greater Ecosystem

How do trees of different ages and sizes contribute to larger ecological systems? Trees offer much to life around us. When trees are young, particularly during their sapling to maturity stages, they are growing rapidly. During this time, seed and fruits form, providing nutrients to animals and vegetation around to consume. They also begin to establish greater root and branch structure that allows shelter for surrounding wildlife. Nesting becomes easier for birds as branches begin to interconnect, while shade is extended on the ground below. Not only are trees are able to grow most rapidly at this stage, but they are also at peak carbon dioxide and other toxic gas storage. Younger trees, up to approximately 35 years old, store nearly double the amount of carbon than older trees that are roughly 150 years in age. They hold onto carbon while emitting oxygen back into the air. In short, the more younger trees that coexist, the more oxygen generated. 

Elderly adult trees offer the same oxygen-producing act, but at a slower rate. During the maturity decline, these trees still provide space for nesting, for both birds and honey bees, but they are the largest in their lifespan, providing a more static, less diverse habitat for wildlife. Forests that contain trees and other foliage staggered in age, on the other hand, offer biodiversity that ensures resilience in an ecosystem.

To learn more or to start the discussion about selling your timber, contact us today.