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Urban trees 'live fast, die young' compared to those in rural forests

phys.org

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Re: Urban trees 'live fast, die young' compared to those in rural forests

#91

Post by cossatot »

sandworm101 wrote: post #58
atulatul wrote: post #32

I highly recommend reading the book "The Hidden Life Of Trees" by Peter Wohlleben There is an informative chapter/section called Street Kids about trees planted along the streets primarily in urban areas. How their health is impacted by having no network of close cousins nearby to communicate/ suppy nutrients via root/fungi, etc. https://www.amazon.com/Hidden-Life-Trees-Illustrated/dp/1771...

There are also some advantages. Urban trees, being more spread out, sometimes have greater sunlight and therefore grow faster. For some trees age isn't the limiting factor but height. They grow until they risk toppling over. So the urban tree does die "young", but is the goal to keep trees alive as long as possible? If it is, then there are lots of things that can be done to slow their growth and prolong their lives.…

The canonical paper on this topic is Edmund Schulman's classic "Longevity under Adversity in Conifers" (1954)[1]

When I worked in a tree-ring dating lab, we always sought out the harshest local environments in a region and then at a given site, the harshest micro-environments (typically water limited but fire protected) because that's where you find the most ragged, pathetic, and correlatively oldest trees around with the most climate sensitivity in their ring patterns. This makes the ideal trees to date and build climate chronologies from.

[1]: https://sci-hub.tw/10.2307/1682970

Re: Urban trees 'live fast, die young' compared to those in rural forests

#92

Post by beat »

kaycebasques wrote: post #89
beat wrote: post #87

Earlier quoted context omitted.

Living in an urban forest, ripping up wild young trees is part of normal yard maintenance. I probably get at least a dozen a year. Two of my full-sized trees in my yard were wild seedlings that I allowed to grow because I like those particular kinds of trees (a catalpa and a sumac), and they were in good locations. This also includes invasive tree species like buckthorn, which is a villain in our area. Buckthorns pop…

I guess one could view urban tree dynamics as extreme selection for certain traits. They have to be pretty, and in a location that won't inconvenience humans, and they can't do anything to inconvenience humans, like cause allergies, and they have to be extremely resilient.

And around here, they have to be ok if it hits -20F sometimes in the winter.

I have a magnolia, and it completely boggles me that it survives and thrives this far north.

Re: Urban trees 'live fast, die young' compared to those in rural forests

#93

Post by sandworm101 »

atulatul wrote: post #61
sandworm101 wrote: post #58

Earlier quoted context omitted.

There are also some advantages. Urban trees, being more spread out, sometimes have greater sunlight and therefore grow faster. For some trees age isn't the limiting factor but height. They grow until they risk toppling over. So the urban tree does die "young", but is the goal to keep trees alive as long as possible? If it is, then there are lots of things that can be done to slow their growth and prolong their lives.…

>but is the goal to keep trees alive as long as possible? For some trees, being 100year old means that the trees are in their late teens/twenties/thirties (source above book). With that in mind, the answer to above question becomes somewhat difficult.

You are also applying mammalian standards to a plant. Trees may indeed be capable of living a very long while, but that does not mean that such lives are normal. A tree can live a full and productive life, reproducing and spreading many times, centuries before its total lifespan. There is also some speculation that trees may be immortal, that if their growth is artificially managed that they may just never have to die. Plants are different than mammals. They don't all have the same definitive life cycles.

Re: Urban trees 'live fast, die young' compared to those in rural forests

#94

Post by abugheratwork »

beat wrote: post #86
atulatul wrote: post #32

I highly recommend reading the book "The Hidden Life Of Trees" by Peter Wohlleben There is an informative chapter/section called Street Kids about trees planted along the streets primarily in urban areas. How their health is impacted by having no network of close cousins nearby to communicate/ suppy nutrients via root/fungi, etc. https://www.amazon.com/Hidden-Life-Trees-Illustrated/dp/1771...

The "close cousins" thing is interesting for me. I live in a tree-lined streets neighborhood. Historically, they chose species on a street-by-street basis. My street was all linden trees for the curb trees (except for a last remaining elm, we've lost most of them to Dutch Elm disease). A few years back, a severe wind storm took out seven of the curb trees on my block, in a cluster (and smashed a few cars in the proce…

I don't know about your hackberry in particular. This has been a topic of fascination for me, though.

Trees connect to each other via symbiotic root fungi called "mycorrhizae". Any given species of plant probably has several species of fungus with which it is compatible. The fungus and the plant form a mutually beneficial pair, but the fungus can additionally connect to other nearby plants. Then you have a network, potentially with multiple plant species.

The network can be used for nutrient storage (summer to winter), nutrient transfer (to offspring), or chemical signalling. ("Bugs attacking. Get ready.") Different species are known to support each other, giving nutrients back and forth and different times of year. Of course, the black walnut will use the network to poison its neighbors.

Playing in my flower pots, I have observed that plants growing right next to sweet potatoes or succulents do better when I forget to water them, but I haven't measured that. In my mind, they're leaching water from their neighbors through the network.

So, it's complicated, and there is such a thing as a bad actor on the network, but basically I don't think your tree will be lonely. I'm optimistic.

Re: Urban trees 'live fast, die young' compared to those in rural forests

#95

Post by sevensor »

RobotCaleb wrote: post #78
sevensor wrote: post #57

Earlier quoted context omitted.

Not to mention people constantly ramming vehicles into them. There's not a tree in my town that doesn't have a big scar on the trunk at bumper level.

Not a single one?

You got me. I exaggerated. A large number of streetside trees in the downtown area have accident scars on them.

Re: Urban trees 'live fast, die young' compared to those in rural forests

#96

Post by icebraining »

DuskStar wrote: post #79
icebraining wrote: post #72

Earlier quoted context omitted.

If job differences are not intrinsic to cities, what is?

Density, maybe?

Yeah, and I'd say those differences in density inevitably cause differences in types of jobs. It's second order, but still intrinsic.

Re: Urban trees 'live fast, die young' compared to those in rural forests

#97

Post by hinkley »

abugheratwork wrote: post #94
beat wrote: post #86

Earlier quoted context omitted.

The "close cousins" thing is interesting for me. I live in a tree-lined streets neighborhood. Historically, they chose species on a street-by-street basis. My street was all linden trees for the curb trees (except for a last remaining elm, we've lost most of them to Dutch Elm disease). A few years back, a severe wind storm took out seven of the curb trees on my block, in a cluster (and smashed a few cars in the proce…

I don't know about your hackberry in particular. This has been a topic of fascination for me, though. Trees connect to each other via symbiotic root fungi called "mycorrhizae". Any given species of plant probably has several species of fungus with which it is compatible. The fungus and the plant form a mutually beneficial pair, but the fungus can additionally connect to other nearby plants. Then you have a network, p…

Roots of the same species can fuse directly. It helps canopy tree species grow up inside of an already closed canopy, and similar to mycorrhizal networks, can spread around sugars and water.

Re: Urban trees 'live fast, die young' compared to those in rural forests

#98

Post by hinkley »

Symmetry wrote: post #29
ekianjo wrote: post #21

Earlier quoted context omitted.

Is this a joke? Life expectancy has been increasing as people left the countryside for the cities. It's not even a matter of debate.

These days it is but back before the revolutions in public health at the turn of the 20th century cities were very unhealthy, so much so that they tended to be net consumers of population from the countryside even when they weren't growing.

Don't forget unions. We like to bag on them but factories with locked doors burning down with the people still inside gave the unions the teeth they needed to get things like that made illegal.

Re: Urban trees 'live fast, die young' compared to those in rural forests

#99

Post by m463 »

bryan11 wrote: post #31
guilhas wrote: post #9

I think a bigger issue is healthy trees being cut in a lot of urban areas. https://www.dailymail.co.uk/news/article-5801627/Great-tree-... Reference to UK, but I can see the same happening in Ireland and Portugal.

Frequently, the first step when building in the US is to rip down any existing trees and completely clear the property

It's kind of sad. Reminds me of the (several) cartoons I saw as a kid where the bulldozers come and conquer the forest.

Re: Urban trees 'live fast, die young' compared to those in rural forests

#100

Post by bluGill »

therein wrote: post #75
ginko wrote: post #39

But wouldn't that be good for carbon capture? Let the tree grow quickly, then when it dies store the wood somewhere and plant a new one.

Store the wood somewhere? Am I naive to think that it will be burned?

Even burning isn't necessarily bad. Wood burned in nature (which we can simulate easily) will leave a lot of unburned carbon behind in the form of charcoal.

You have to deal with the air pollution though (which is a real problem, but been going on for longer than humans).

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