The Oldest Tree in the World

The Oldest Tree in the World
by Summer Price, Trees Atlanta Intern

We all know trees can live really long lives. It’s no surprise that they typically live longer than humans and perhaps most everything else on the planet. Trees can live anywhere from less than 100 years to more than a few thousand years depending on the species.  However, one species in particular outlives them all. The Great Basin Bristlecone Pine (Pinus longaeva) has been deemed the oldest tree in existence, reaching an age of over 5,000 years old.

The bristlecone pine’s success in living a long life can be attributed to the harsh conditions it lives in. Very cold temperatures associated with high winds, in addition to a slow growth rate, create dense wood. This means some years they grow so slowly, they don’t add a ring of growth. Due to the slow growth and dense wood, the bristlecone pine is resistant to insects, fungi, rot, and erosion. The lack of vegetation where they grow make bristlecone pines rarely affected by wildfires. These slow-growing trees can reach a height of 50 feet and a trunk diameter of 154 inches.

Even the needles on these fascinating trees live up to 30 years long. This allows the trees to conserve energy by not having to reproduce new ones. It takes about two years for the bristlecone pine cone to reach maturity, which is unique amongst trees in the conifer family. The bristlecone pine gets its name from the cones whose scales appear to have a claw-like bristle.

My biggest question when learning about the bristlecone pine and its exceptionally long life is how someone determined that this tree was the oldest tree in the first place. The easiest way to determine the age of a tree is through dendrochronology. Dendrochronology is the science of dating tree rings, a practice that has been used for about 500 years. One way to determine the age of a tree is to cut it down near the base to count its rings, but of course no one wants to cut down a tree that is possibly thousands of years old! So what else can be done to determine the age of a tree?

Good news! There is a way to determine the age of a tree without killing it. An increment borer is a tool that can be drilled into the center of a tree and retracted removing a cylinder of the trunk. The thin cylinder extracted from the tree will show all of the tree’s rings which can accurately determine its age. This would be the best and most effective method when determining the age of a tree that does not need to be cut down, such as these ancient bristlecone pines.

Unfortunately, we have not been blessed with the presence of the bristlecone pines in Atlanta. However, there are many opportunities when travelling in California, Utah and Nevada in the White Mountains, and Inyo Mountains to view the old wonders.