The lifespan of some trees can seem almost unbelievable to us.
With even shorter-lived species like silver birch living for 100 years or more, and the longest-living trees living for more than ten thousand years, it can be hard to comprehend what the life of a tree must be like.
It’s extremely unlikely that you’ll witness the birth and natural death of a tree in one human lifetime.
The lifespan of trees, long though it can be, varies dramatically among different types. Faster-growing trees tend to have shorter lifespans.
Palm trees, for example, may grow up to 6 feet per year but only live for between 60 and a little more than 100 years, depending on the variety.
This is not an absolute rule, as we discussed in our article on how long it takes for trees to grow, but it is a reasonable guide.
Shorter-lived Trees
Birch trees are a pioneer species, meaning that they happily populate open ground; they were one of the first trees to take root after the last Ice Age.
Birch will quickly colonize land cleared by forest fires, providing much-needed food and habitat for displaced animals. They grow fast, but, as mentioned above in the case of the silver birch, they don’t live for very long.
Rowan, or mountain ash, is another pioneer species. In addition to being a common field and woodland tree, it also grows at higher altitudes than many other trees. Rowan is a beautiful little tree, but will usually only live for between 100-200 years.
The bitternut hickory, American beech, American basswood, and eastern cottonwood are all known for having lifespans of less than 300 years. A sugar maple tree may live for 400 years; the lifespan of a sycamore is about the same.
Faster-growing fruit trees are among the shorter-lived species, but modern research and insight has shown that they live far longer than was previously thought. While the maximum lifespan of fruit trees had been placed at less than 100 years in some cases, they are now being shown to live for much longer.
Apple and pear trees can live well into their hundreds, and even cherry trees, which were once thought to live only for 50-60 years, may live to 100 at the very least.
As with so many aspects of tree growth, lifespan is significantly affected by where the tree lives and how it grows. A tree in a harsh climate and landscape, or a tree planted in an area other than that in which it would normally grow and thrive, will have a shorter lifespan than the same type of tree growing in optimum conditions.
Human Impact on the Lifespan of Trees
Which brings us to the Bradford pear. Currently considered by many to be a scourge on American neighborhoods, the Bradford pear is a cultivar created by the USDA from a wild pear tree found growing in China.
Initially revered for its tolerance to poor soil conditions and showy displays year-round, the Bradford pear tends to grow quickly and then die catastrophically after 15-20 (maybe 30) years as it lacks the structural stability to support itself in storms or under the weight of rain, snow, or ice.
What’s worse is that, far from being the sterile tree it was promised to be, it’s currently cross-pollinating left, right, and center, creating more Bradford pears than anyone every wanted.
This is a very short-lived tree whose lifespan (and behavior) causes no end of problems, but it’s important to remember that this is not a naturally occurring tree.
It was created this way, badly, by people who clearly didn’t quite understand what they were doing. Nature tends not to create trees that grow larger than their frames can support.
Longer-lived Trees
The deep-rooted Oak is one of the longer-living broadleaved trees. Its exact lifespan will depend on the variety, but in general, oaks live well into their hundreds. The Bowthorpe oak and Knightwood oak in the UK are thought to be over 1000 and 500 years old, respectively.
The baobab tree, a wonderfully shaped tree that can sometimes look almost upside down, is native to Australia, Madagascar, India, and the African mainland.
Baobabs can live for more than 3000 years and are invaluable to local communities for food, medicine, material for making rope and baskets, dye, and water storage in their vast, hollow trunks: 300 different uses have been claimed.
Ginkgo biloba, a species that’s been around for an incredible 270 million years, can live for 3000 years. Scientists are now beginning to understand that the ginkgos longevity may be due to its remarkable immune system, which appears not to age in the same way that the immune systems of other organisms do.
Olive trees can also live for thousands of years, maybe 5000 or more according to some experts. There is an olive tree in Crete estimated by university scientists to be more than 4000 years old, and a tree in Bethlehem thought by the Palestinian Ministry of Agriculture to be around 5000.
Yew, bristlecone pine, and coast redwood trees are other species renowned for having extremely long lifespans. In fact, they’ve been proven beyond doubt to be some of the oldest trees in the world.
The World’s Oldest Trees
Throughout the world, there are certain trees that deserve a special mention. And one of them may surprise you!
Bristlecone pines
Methuselah, a Great Basin bristlecone pine tree in California, has been confirmed to be 4855 years old. It’s only superseded in the distinction of being the confirmed oldest tree in the world by another, unnamed tree of its same species: that tree has been alive for 5070 years.
Ancient yews
Yew trees are renowned for living to extremely old ages, and the UK has more ancient yews than any other country in Europe. A yew in the churchyard of Saint Cynog’s church in Defynnog, Wales is thought to be more than 5000 years old. The Fortingall yew in Scotland is between 2000-3000 years old.
Hyperion
Not that old, but extraordinarily tall, Hyperion is a coast redwood in California and officially the tallest tree in the world. When last measured, it was 380.1 feet high: that’s 68 feet taller than Big Ben!
Hyperion grows in Redwood National Park among other giants, and its age is estimated at around 700. Given that its species can live for thousands of years, it’s probably only going to get taller.
(The second-tallest tree in the world, Centurion, is 329.7 feet in height. Centurion lives in Tasmania and is a Eucalyptus regnans tree. It’s the tallest hardwood tree in the world; Hyperion, as a redwood, is softwood.)
Pando
by J Zapell, Public domain, via Wikimedia Commons
And then there’s Pando. Thought to be somewhere between 10,000 and 13,000 years old, Pando is one organism comprised of, at present, approximately 47,000 separate tree stems. A Quaking aspen tree, it covers around 106 acres in Utah in the United States. Pando is Latin for “I spread”.
For many years, it was thought to be an ancient forest like any other, but scientists discovered that it is in fact a clonal colony: each of its 47,000 aspen trees is identical to the rest, and they all share the same root system.
Unfortunately, Pando has been shrinking in recent decades, and researchers fear that it may be dying. Its stems were all aging — no new ones were growing — and it seemed to have lost the ability to replenish its dying stems.
However, scientists have found that fencing off certain sections of Pando to protect it from grazing predators and human threats have allowed it to regenerate in places and grow new stems.
There is hope that, through better management and protection schemes, Pando may yet have a chance to regain its equilibrium and live for thousands of years to come.
Help Trees to Keep Living Long
The lifespan of trees will continue to fascinate us, with our relatively short lives. Most types of tree are able to live well beyond a hundred years, and some, like Pando, reach unfathomable ages. But recent research from around the world shows that ancient trees are dying at an unprecedented rate.
In the last decade, a number of Africa’s oldest baobab trees have suddenly died or sickened, the cause is thought to be climate change. Pando is suffering, and venerable trees everywhere are under constant threat from human interference and anthropogenic changes to the environment.
For trees to continue to grow for thousands of years, it’s critical that we show them the respect and care that they deserve. Thankfully, many scientists are now beginning to understand how our actions are detrimental to the other species with whom we share our planet and working to protect habitats (and trees) under threat.
Now it’s just up to each of us do the same!
