Do trees grow old?

Okay, I know that sounds silly, but hang with me. All life, AFAIK, can die of predation, disease and injury. Animals that don’t die of those causes will sooner or later die of old age.

Trees and other plants just seem to keep growing. Do any plants age? As in “reach prime maturity and then go downhill”?

Yep. We are all subject to entropy.
My neighbor across the street had to have her tree removed last Summer. There was no apparent disease, it just started putting out less and less leaves each year, then the branches died, until it finally posed a hazard and had to come down.

Case in Point: I like to grow choleus, and I’ve found that at some point after maturity, the plants would get woody, leggy, and eventually die. Producing flowers seemed to trigger and accelerate this, but even pinching off the buds only slowed the process down.

The only way I was able to grant ‘immortality’ to the plants was to take cuttings.

hope that helps, and, BTW, come on over to the Edwardian House Party; it does need livening up! :slight_smile:


I could never eat a mouse raw…their little feet are probably real cold going down. :rolleyes:

Cecil’s answer to this:

“Drink your coffee! Remember, there are people sleeping in China.”

Yep, they do.

Plants grow outward, not upward, except at the very tips (leaf buds, fruit, root tips). For years-old plants, that means the centers are basically dead material which doesn’t get replaced. This is fine as long as any outside agents don’t get in and damage it. But there are several things that can let these things in:[ul][li]A branch can grow too heavy for its angle. It breaks off and exposes the center.[/li][li]Lightning can damage the bark and the living part just underneath.[/li][li]Fungal growths can undermine the bark, allowing even more outsiders in.[/li][li]Animals eat the bark (beavers, for example).[/ul][/li]
Once the center part gets damaged, support for the plant itself starts to fail until the whole tree falls over or too many branches fall off, not leaving enough leaves to generate food for the plant.

Trees also genetically age. That is, the chromosomes gradually lose their tips after repeated mitosis. They come to a point where the daughter cells are unviable. That part stops growing branches and leaves, and soon the bark dies, leaving the dead core. Trees’ genetic age is much longer than animals’ due to their lower metabolism because they don’t have to move around.

There are trees that live for millenia. Can’t recall their name, but they’re desert trees. They look dead, but there’s a little strip of bark that’s still alive and slowly migrates around the tree growing the various branchs.

Wrong thinking is punished, right thinking is just as swiftly rewarded. You’ll find it an effective combination.

A lifetime of a tree is given in planting books. 40 years, 50 years, etc. Sequoias have really long ones.

Creosote lives a long time.

joshua national forest (in calif?) i think has whats considered the worlds oldest living tree . . a coupla thousands years old. its named “methusala” (sp?). i guess josh trees live a long time. do a search on it if you like.

I think bristlecone pines are the oldest trees in the world…I remember reading that somewhere long ago…

Not to be snippy, but Jesus, guys! Read the friggin article from Cecil!

Once again,

Well, if cloning counts, I think the creosote and the quaking aspen and King’s Holly (Lomatia tasmanica) have the B. Cone pine beat by a mile.

from the above link in my previous post

Finally, a question I am an expert on!
Yes, trees have life spans as Cecil so expertly explained.
We genetically select trees for fast growth in order to produce more wood on fewer acres in a shorter time frame. Depending on the species you are interested in–and on where it is growing–sawtimber can be harvested as young as 25-30 years, although most private landowners grow their timber a little longer. A lot of people make the assumption that these harvests are taking place on “virgin timber” hundreds of years old. (Please note I am talking about the Southern US here, not the far west coast of the US where some species are truly long lived). In actuality, managed stands of loblolly, slash, or shortleaf pine will be only 30-50 years–maybe 80 at the most. Even longleaf isn’t much more than that. So, they get replanted or regenerated naturally and start over. In fact, we can do a first thinning at age 12-15 and by the time the stand is 20-35, most people assume it’s really old! Even most of the hardwoods down South don’t grow that long. 300 years is about maximum for most oaks.
Not only do the trees age, but they show definite signs of aging. Old loblolly pines for instance (say 60 years) start getting red heart disease–a fungus that makes them attractive to woodpeckers. You can tell their growth is slowing by looking at the bark–the bark gets platy and flattens out.
More than you wanted to know, I’m sure!

Some trees when they reach maturity flower and die (well, AFAIK, only certain palm species). A really spectacular example of this is the Talipot palm (Corypha umbraculifera). When the tree reaches it’s maximum age, it sends up a massive inflorescence (one of the largest inflorescences int he world). After it sets fruit it dies. All of the tree’s energy is spent on producing fruit, so it takes a lot out of the tree to do it. You can see a picture of it in flower here:

Usually, other types of trees eventually decline, as the other posters have said.

It’s worth the risk of burning, to have a second chance…


Are you sure it’s the Joshua Tree that has the long life span? It might be - but I always assumed it wast the Giant Redwoods that lived quite long. Them, and the bristlecone.

I visit Yosemite and Sequoia Parks a lot (hence my username) and I remember being told that the reason the Giant Sequoias live so long (thousands of years) is that they have some sort of enzyme (or something) in their bark that makes them resistant to pests and parasites. That, apparently, and just a naturally long life span. Shit, considering my username, you’d think I’d know more about this, wouldn’t you?

i think the unforgivin is right; “methusala” is a bristlecone and the bristlecones are very long-lived. the tree is not marked so as to deter vandals and souvenir hunters.

Originally posted by yosemitebabe:

Are you sure it’s the Joshua Tree that has the long life span? It might be - but I always assumed it wast the Giant Redwoods that lived quite long. Them, and the bristlecone.**[/QOUTE]

It’s not the joshua tree. Joshua trees are a species of yucca (Yucca brevifolia). It is the bristlecone pine, which lives near or at the treeline in the Sierra Nevadas, not the desert.

It’s not an enzyme in their bark that makes them resistant to pests. It’s tannic acid (which is what makes tea reddish, and amazonian rivers too). The bark has quite a bit of it which is why the bark is reddish. Tannic acid is also kind of a fire retardant, IIRC. The bark can also be up to three feet thick, and is spongy, which is why small forest fires only scorch the outside while protecting the inside (though, i’ve seen trees with the centers hollowed out from fire, but the tree was still alive). Bugs don’t like eating bark with tannic acid, so they pretty much leave the trees alone.

It’s worth the risk of burning, to have a second chance…

ok, no more trying to save me some time by using the ubb codes already there, and adding my own! Horror…well, the second paragraph is mine, in the quoted section.

It’s worth the risk of burning, to have a second chance…

Doobeius—Yes, that’s it! I knew it was something in the tree bark that protected the tree. Thanks for giving the proper details.

And I didn’t think the Joshua tree was known for longevity. I didn’t know it was related to the Yucca, but it is such a damned odd (wonderfully odd) looking thing, I knew it wasn’t a “regular” tree.

Andros- Do you think the board pays less attention to Cecil than it did even 2-3 months ago? Or maybe it is just the more long term members and the newer onces aren’t as aware of who/what Cecil is?

Oh, I’m gonna keep using these #%@&* codes 'til I get 'em right.

Well, imagine the tip of one of it’s branches stuck on the ground, and you have your basic yucca. Odd things too. They have kind of a surreal look. They do cast more shade than they look like they’d give also. The stem structure of the Joshua tree would look very much like that of a palm tree.

It’s worth the risk of burning, to have a second chance…

Jois/andros -

Perhaps some of the newbies aren’t aware of who Cecil is or have read none of his books or columns. I myself have read all but the TOTSD and have several on the shelf next to me. Point out the column (as you did) so that we can all learn from it. But if the SDMB exists only to point to a Cecil column and say that’s that, then what is the point. Perhaps some of his classics need to be updated in light of research/discovery since the original was written. Knowledge is not a static thing. I think most of use are here to exchange knowledge and ideas with other members. Without that, the SDMB is just another (albiet a much more authoritative)