Trees do have a lifespan, how long they would live naturally without outside factors depends on the species.
The different lifespan of trees plays a part in the maturation of the ecosystem that they live in.
In my area, red alders are fast growing trees with relatively short life’s spans, followed by Douglas fir then Cedar. Red alders have symbiotic mycorrhiza that form nodules on their roots. These mycorrhiza help the alder and surrounding plants by converting nitrogen in the soil into forms usable by plants.
This is speaking very broadly, we have other tree species in my area but it gives you a rough idea of tree succession.
Depends on the tree. Birch trees grow fast and don’t usually live more than 140 years. Oak trees grow for 300, hang around for 300, and slowly decline from there. Maples 100 to 400. Wild pears around 50 years. Apple 100. Some conifers can be very very old.
Most trees have a window of viability, after which point the stress of environmental factors becomes insurmountable (edit to add: insurmountable because their systems can no longer transport energy or fight disease). However, there are trees like ginkgo that can basically survive indefinitely, i.e they are killed rather than die of old age.
Farmers regularly replant fruit trees. Go into a forest. The trees, fallen over, aren’t all dead due to fire or disease. Wind does push over many. I’ve seen where high winds have upended trees and many were broken off halfway down the tree
Coastal Redwoods can have a very long life span if unimpeded. There are records of some being over 3000 years old. These are old growth redwoods are rare. Second and third growth redwoods will grow in a ring around where the old growth once stood. It could be argued that they can live forever in the sense that the second and third growth is a continuation of the first. Personally I think of them more as descendants. I’m lucky enough to live around these giant trees. A lot of local folklore claims redwoods to be immortal. But there also a ton of weed and psychedelics up here too lol. Regardless, trees do age, as everything else does as time passes. If you ever get the chance, I highly recommend visiting the redwood forests in Northern California. They are absolutely astonishing!
I got to see some of the oldest trees on earth, the bristlecone pines high in the White Mountains of Southern California, and I think the reason they are so old and still going is that they are so far from humans. Wonderful, twisted, hearty trees clinging to the top of an alternately hot and cold and windy mountain. The oldest is thought to be over 4800 years old. So we know they can go that long, and there are some that might be older in Chile.
If you include them clone forests are probably the winner.
The oldest known one is estimated at 9k-16k years old; if not the oldest known bristlecone pines are just under 5000 years old.
I suspect the upper limit for clone forests is constrained by the glacial cycle eventually rendering their growing locations unsuitable. Pando dates back to early in the most recent thaw cycle.
Giant Sequoias have a lifespans of a few thousand years, but the way they live means that, over time, their vulnerability approaches 100%.
They grow throughout their lives – reaching the range of a 20+ story building. But their root structure is shallow, especially compared to other tall trees. That, all by itself, means that the tree will become less stable over time, as the shallow roots don’t ‘hold on’ to the ground as well. And, even it does take over 3,000 years, at some point, a strong enough wind will blow the tree over.
They absolutely do. Drive through any neighborhood that had Bradford pears planted 20-25 years ago and you’ll see a bunch that had to be cut down or that were topped to attempt to save them a little longer. Once they reach that age they just start breaking.
Many trees can overgrow with time, their branches becoming too heavy to properly be supported and will crack under their own weight. And even a well fit branch can bend in just the wrong way during a storm or windy day, then snap!
This doesn’t always kill the tree but it does leave it massively vulnerable and at risk of further damage, so this is one of the more common ends to tree lives.
Barring that there’s the matter of terrain, if a tree grows too tall or heavy for the roots to keep it down they can topple and that’s usually an end as well.
Like the other comments have mentioned there’s many types of trees that are very well suited for incredible lifespans and usually only die to external factors. Some trees are well evolved for near permanence while others live a brief life of mere decades. In the end the species and environment itself are the big limiters.
you can tell the age of a live oak by its resemblance to an octopus because as it ages the limbs get heavy and force them downwards. Also the trunks get thicker. When a tree has “aged out” you will see it begin to die from the center outward.
Coppiced trees seem to have a near infinite life-cycle, right? Nature coppices trees all the time, and humans have been doing it for a super long time
trees do sort of age in the sense that they need to grow each year and at a certain point, their growth is too intensive and adds so much weight/mass that limbs breaking becomes ineviable.
Trees with single trunks generally have individual lifespans constrained by geometric factors: they eventually grow large enough to strangle themselves. Thicketing trees, where a network of roots supports many trunks, get around this limitation. Although individual trunks die, they are constantly replaced by new trunks and the whole plant will survive as long as no external circumstances kill it. Aspens and sassafras are examples.
A lot of comments that dont follow guidelines here.
The way that trees grow means that most of the active and living parts of a tree at any given point are the most recent growth from the past few years. The rest of the tissues (like those within the trunk) are not living. The plant tissues that you see are all, generally speaking, pretty young, even on a very old tree. The tissues grow from meristematic cells in the cambium, which can be thought of similar to stem cells in humans, and proliferate for the tree’s whole life to create all of its tissues. Systematic cancers are not a concern for plants, but over time mutations could compromise the functioning of these cells, so plants have a large number of cellular processes for “quality control” of duplicating cells. https://pmc.ncbi.nlm.nih.gov/articles/PMC10933334/#:~:text=unlike%20animals%2C%20plant%20stem%20cells,a%20deterioration%20of%20cell%20physiology.
So that’s the first part, essentially, that trees “don’t age” because even a very old tree has mostly tissues that are physiologically quite young.
The second part, if you removed all environmental factors, would a tree live forever? Hard to say.
Trees follow physics. Water and the way it moves through the stem of a tree is probably the most important thing to consider here. A tree can only get so tall. Once you surpass a certain height, trees can no longer move water from their roots to their leaf tips, no matter how saturated the soil is. You would certainly get dieback as a result. A tree can also only get so heavy. After a point, the weight of branches create excessive strain. With unlimited growth, you’ll eventually see branches that are very heavy.
Typically, these are the places where your environmental stressors would step in to hasten an old tree along. Heavy, stressed branch junctions break, creating inviting wounds for fungal and insect pathogens. Drought is a big killer as well since large trees have large need for water to support their biomass. Without these acute stressors, i’m inclined to say that you’d just get a really messed up tree over long time periods, particularly since many species of tree have some capacity to resprout from living roots. Of course, this is not a realistic scenario.
There are things like Sponges or Hydra or Jellyfish that seem practically immortal, but the reality is that every time a cell divides there’s a risk of an error. Animals can live extremely long times with a simple design and layers of genetic repair mechanisms, but nothing lives forever.
I had a professor who said that complex life gave up immortality for sexual reproduction.
Atmospheric nitrogen fixation isn’t just uncommon in fungi, it’s nonexistent. Alders do form mycorrhizal associations, and the mycorrhizal fungi do enhance nitrogen uptake by accessing organic nitrogen, as you state, and also enhance uptake of other minerals like phosphorus from the soil. But they do not fix atmospheric nitrogen. Alders also form root nodules with actinomycetes that do fix atmospheric nitrogen. These n-fixing actinomycetes are a different group of bacteria than the n-fixing rhizobial bacteria that associate with legumes. All of which has nothing directly to do with OP’s original question. It’s just one of my personal crusades to disabuse people of the notion that mycorrhizal fungi, or any other fungi, fix atmospheric nitrogen. Mycorrhizae are awesome, but they don’t fix nitrogen.
There are many species of tree, some live for a short time and some seemingly want to experience the heat death of the universe.
For instance, ‘Old Tjikko’ is a tree in a undisclosed location somewhere in Sweden ‘Dalarna’ and it’s ~9550 years old.
This tree was around when Babylon was a thing.
This tree was around when the first pyramid of Egypt was built.
This tree was around when the last ice of the ice age receded…
Trees age, and they can theoretically live forever yes, as long as the root system keeps growing and eventually grows new trees to grow new roots to grow new trees, but very few trees can even live that long, and even fewer have.
So a singular tree has a finite lifespan, which is just the natural limitation of life, because most things rarely lives long enough for that to become a common trait among its species, oldest singular trees around is around 5000 years, give or take, depending on what continent you are looking at one tree in north america, one tree in south america, one tree in europe, one tree in asia, oldest african tree was half that, and the one i know about collapsed over a decade ago.
and theoretically there can be a tree thats part of a root system in ociania that could be 200 million years old, however due to the fact that the tree was only discovered 3 decades ago, cause there are so few left, thats unlikely to be found out if true, or how true.
So yes, trees do age, in the same way humans does, and even without droughts, parasites, forest fires, etc, it will eventually die, usually from its own growth, since the core of the tree tends to be the first thing to rot
Yes, trees do age, and while some can live for centuries or even millennia, they are not immortal and will eventually die. Trees can die from various factors like disease, pests, fire, or environmental changes, rather than solely due to old age.
In this thread no-one has mentioned lightning, a killer of trees. I’d have thought that while the chance of a tree being struck is low, over thousands of years it becomes likely. Are there places that never get lightning, even over thousands of years?
If you where to take cuttings from a said tree and grow from them and cut them, as long as you kept doing so the “same” tree would still exist although then we go into if you replace the handle and then the head of a broom is it still the same broom debate…
There is a very large tree network of aspens in the US that are all clones of each other and interconnected so theoretically I would say yes it is possible for them to live forever but realistically a fungus/fire/human/drought or other thing will eventually take them out
I’ve tried to find the video, but Tony Robinson did one of his walks through Sherwood Forest many years ago and it included a segment with an arborist who is employed to help care for the historical oaks there.
I remember him describing that the white oaks there are about a 900 year tree barring fire, major storm, or disease. They spend 300 years obtaining their full height, 300 years of ‘adulthood’, and 300 slowly dying. So most of the trees that were young in the Robin Hood days are now almost gone, but replaced by the offspring of those trees.
Comments
Trees do have a lifespan, how long they would live naturally without outside factors depends on the species.
The different lifespan of trees plays a part in the maturation of the ecosystem that they live in.
In my area, red alders are fast growing trees with relatively short life’s spans, followed by Douglas fir then Cedar. Red alders have symbiotic mycorrhiza that form nodules on their roots. These mycorrhiza help the alder and surrounding plants by converting nitrogen in the soil into forms usable by plants.
This is speaking very broadly, we have other tree species in my area but it gives you a rough idea of tree succession.
I don’t have any specific studies offhand to cite, but here are some articles that talk about tree lifespans:
https://treeguidence.com/tree-lifespans-factors-that-affect-how-long-trees-live/
https://www.ncesc.com/geographic-faq/what-is-the-lifespan-of-a-tree/
Depends on the tree. Birch trees grow fast and don’t usually live more than 140 years. Oak trees grow for 300, hang around for 300, and slowly decline from there. Maples 100 to 400. Wild pears around 50 years. Apple 100. Some conifers can be very very old.
Most trees have a window of viability, after which point the stress of environmental factors becomes insurmountable (edit to add: insurmountable because their systems can no longer transport energy or fight disease). However, there are trees like ginkgo that can basically survive indefinitely, i.e they are killed rather than die of old age.
Farmers regularly replant fruit trees. Go into a forest. The trees, fallen over, aren’t all dead due to fire or disease. Wind does push over many. I’ve seen where high winds have upended trees and many were broken off halfway down the tree
Coastal Redwoods can have a very long life span if unimpeded. There are records of some being over 3000 years old. These are old growth redwoods are rare. Second and third growth redwoods will grow in a ring around where the old growth once stood. It could be argued that they can live forever in the sense that the second and third growth is a continuation of the first. Personally I think of them more as descendants. I’m lucky enough to live around these giant trees. A lot of local folklore claims redwoods to be immortal. But there also a ton of weed and psychedelics up here too lol. Regardless, trees do age, as everything else does as time passes. If you ever get the chance, I highly recommend visiting the redwood forests in Northern California. They are absolutely astonishing!
I got to see some of the oldest trees on earth, the bristlecone pines high in the White Mountains of Southern California, and I think the reason they are so old and still going is that they are so far from humans. Wonderful, twisted, hearty trees clinging to the top of an alternately hot and cold and windy mountain. The oldest is thought to be over 4800 years old. So we know they can go that long, and there are some that might be older in Chile.
If you include them clone forests are probably the winner.
The oldest known one is estimated at 9k-16k years old; if not the oldest known bristlecone pines are just under 5000 years old.
I suspect the upper limit for clone forests is constrained by the glacial cycle eventually rendering their growing locations unsuitable. Pando dates back to early in the most recent thaw cycle.
https://en.wikipedia.org/wiki/Pando_(tree)
https://en.wikipedia.org/wiki/List_of_oldest_trees
If you count Pando, which is also the largest living thing on Earth, it could be as old as 14,000-16,000 years old.
It’s a single tree that’s an entire forest – the same roots just keep spreading out and rising up new trunks.
Trees do age, and they do have limited lifespan.
Giant Sequoias have a lifespans of a few thousand years, but the way they live means that, over time, their vulnerability approaches 100%.
They grow throughout their lives – reaching the range of a 20+ story building. But their root structure is shallow, especially compared to other tall trees. That, all by itself, means that the tree will become less stable over time, as the shallow roots don’t ‘hold on’ to the ground as well. And, even it does take over 3,000 years, at some point, a strong enough wind will blow the tree over.
You can usually tell how old a tree is by looking at the rings around the tree.
https://www.wikihow.com/images/thumb/f/fe/Count-Tree-Rings-Step-3.jpg/v4-460px-Count-Tree-Rings-Step-3.jpg
They absolutely do. Drive through any neighborhood that had Bradford pears planted 20-25 years ago and you’ll see a bunch that had to be cut down or that were topped to attempt to save them a little longer. Once they reach that age they just start breaking.
Many trees can overgrow with time, their branches becoming too heavy to properly be supported and will crack under their own weight. And even a well fit branch can bend in just the wrong way during a storm or windy day, then snap!
This doesn’t always kill the tree but it does leave it massively vulnerable and at risk of further damage, so this is one of the more common ends to tree lives.
Barring that there’s the matter of terrain, if a tree grows too tall or heavy for the roots to keep it down they can topple and that’s usually an end as well.
Like the other comments have mentioned there’s many types of trees that are very well suited for incredible lifespans and usually only die to external factors. Some trees are well evolved for near permanence while others live a brief life of mere decades. In the end the species and environment itself are the big limiters.
you can tell the age of a live oak by its resemblance to an octopus because as it ages the limbs get heavy and force them downwards. Also the trunks get thicker. When a tree has “aged out” you will see it begin to die from the center outward.
Coppiced trees seem to have a near infinite life-cycle, right? Nature coppices trees all the time, and humans have been doing it for a super long time
trees do sort of age in the sense that they need to grow each year and at a certain point, their growth is too intensive and adds so much weight/mass that limbs breaking becomes ineviable.
Trees with single trunks generally have individual lifespans constrained by geometric factors: they eventually grow large enough to strangle themselves. Thicketing trees, where a network of roots supports many trunks, get around this limitation. Although individual trunks die, they are constantly replaced by new trunks and the whole plant will survive as long as no external circumstances kill it. Aspens and sassafras are examples.
A lot of comments that dont follow guidelines here.
The way that trees grow means that most of the active and living parts of a tree at any given point are the most recent growth from the past few years. The rest of the tissues (like those within the trunk) are not living. The plant tissues that you see are all, generally speaking, pretty young, even on a very old tree. The tissues grow from meristematic cells in the cambium, which can be thought of similar to stem cells in humans, and proliferate for the tree’s whole life to create all of its tissues. Systematic cancers are not a concern for plants, but over time mutations could compromise the functioning of these cells, so plants have a large number of cellular processes for “quality control” of duplicating cells. https://pmc.ncbi.nlm.nih.gov/articles/PMC10933334/#:~:text=unlike%20animals%2C%20plant%20stem%20cells,a%20deterioration%20of%20cell%20physiology.
So that’s the first part, essentially, that trees “don’t age” because even a very old tree has mostly tissues that are physiologically quite young.
The second part, if you removed all environmental factors, would a tree live forever? Hard to say.
Trees follow physics. Water and the way it moves through the stem of a tree is probably the most important thing to consider here. A tree can only get so tall. Once you surpass a certain height, trees can no longer move water from their roots to their leaf tips, no matter how saturated the soil is. You would certainly get dieback as a result. A tree can also only get so heavy. After a point, the weight of branches create excessive strain. With unlimited growth, you’ll eventually see branches that are very heavy.
Typically, these are the places where your environmental stressors would step in to hasten an old tree along. Heavy, stressed branch junctions break, creating inviting wounds for fungal and insect pathogens. Drought is a big killer as well since large trees have large need for water to support their biomass. Without these acute stressors, i’m inclined to say that you’d just get a really messed up tree over long time periods, particularly since many species of tree have some capacity to resprout from living roots. Of course, this is not a realistic scenario.
Here’s another paper that discusses some of the aging aspects in a later section; https://www.fs.usda.gov/psw/publications/groover/psw_2017_groover001.pdf
There are things like Sponges or Hydra or Jellyfish that seem practically immortal, but the reality is that every time a cell divides there’s a risk of an error. Animals can live extremely long times with a simple design and layers of genetic repair mechanisms, but nothing lives forever.
I had a professor who said that complex life gave up immortality for sexual reproduction.
Atmospheric nitrogen fixation isn’t just uncommon in fungi, it’s nonexistent. Alders do form mycorrhizal associations, and the mycorrhizal fungi do enhance nitrogen uptake by accessing organic nitrogen, as you state, and also enhance uptake of other minerals like phosphorus from the soil. But they do not fix atmospheric nitrogen. Alders also form root nodules with actinomycetes that do fix atmospheric nitrogen. These n-fixing actinomycetes are a different group of bacteria than the n-fixing rhizobial bacteria that associate with legumes. All of which has nothing directly to do with OP’s original question. It’s just one of my personal crusades to disabuse people of the notion that mycorrhizal fungi, or any other fungi, fix atmospheric nitrogen. Mycorrhizae are awesome, but they don’t fix nitrogen.
There are many species of tree, some live for a short time and some seemingly want to experience the heat death of the universe.
For instance, ‘Old Tjikko’ is a tree in a undisclosed location somewhere in Sweden ‘Dalarna’ and it’s ~9550 years old.
This tree was around when Babylon was a thing.
This tree was around when the first pyramid of Egypt was built.
This tree was around when the last ice of the ice age receded…
Trees age, and they can theoretically live forever yes, as long as the root system keeps growing and eventually grows new trees to grow new roots to grow new trees, but very few trees can even live that long, and even fewer have.
So a singular tree has a finite lifespan, which is just the natural limitation of life, because most things rarely lives long enough for that to become a common trait among its species, oldest singular trees around is around 5000 years, give or take, depending on what continent you are looking at one tree in north america, one tree in south america, one tree in europe, one tree in asia, oldest african tree was half that, and the one i know about collapsed over a decade ago.
and theoretically there can be a tree thats part of a root system in ociania that could be 200 million years old, however due to the fact that the tree was only discovered 3 decades ago, cause there are so few left, thats unlikely to be found out if true, or how true.
So yes, trees do age, in the same way humans does, and even without droughts, parasites, forest fires, etc, it will eventually die, usually from its own growth, since the core of the tree tends to be the first thing to rot
Yes, trees do age, and while some can live for centuries or even millennia, they are not immortal and will eventually die. Trees can die from various factors like disease, pests, fire, or environmental changes, rather than solely due to old age.
In this thread no-one has mentioned lightning, a killer of trees. I’d have thought that while the chance of a tree being struck is low, over thousands of years it becomes likely. Are there places that never get lightning, even over thousands of years?
If you where to take cuttings from a said tree and grow from them and cut them, as long as you kept doing so the “same” tree would still exist although then we go into if you replace the handle and then the head of a broom is it still the same broom debate…
There is a very large tree network of aspens in the US that are all clones of each other and interconnected so theoretically I would say yes it is possible for them to live forever but realistically a fungus/fire/human/drought or other thing will eventually take them out
I’ve tried to find the video, but Tony Robinson did one of his walks through Sherwood Forest many years ago and it included a segment with an arborist who is employed to help care for the historical oaks there.
I remember him describing that the white oaks there are about a 900 year tree barring fire, major storm, or disease. They spend 300 years obtaining their full height, 300 years of ‘adulthood’, and 300 slowly dying. So most of the trees that were young in the Robin Hood days are now almost gone, but replaced by the offspring of those trees.