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by Firerouge 722 days ago
Trees per acre seems like a seriously misleading statistic.

A freshly planted tree farm is going to have the highest trees per acre, but be the most useless forest.

I would expect a few old growth trees in an acre would be a substantially better forest, visually, environmentally, and ecologically, than having three times as many young trees.

4 comments

I think you and parent comment might actually agree. The 3x trees is an indication of too much, too many small trees, too much fuel. Places that burn and recover lose their "excess" trees. The trees get more space and are healthy top to bottom.

OTOH, tree farm trees are bred to have few branches and are planted very close together. Tree farms grow tree trunks, not trees.

There is a line of thought, which honestly I think comes from the timber industry, that growing trees are a bigger carbon sink than existing trees. They do argue that the tree farm is actually better because it is growing. I'm extremely skeptical of that claim. Particularly skeptical because the trees in tree farms are so unhealthy, the total amount of green vegetative surface on them is confined to a small canopy and has no vertical depth.

In comparison, old growth vs tree farm is night and day for ecology. Tree farms are very dense, rodents thrive in them but not necessarily much else. Old growth OTOH is generally a pleasure to walk through.

> I would expect a few old growth trees in an acre would be a substantially better forest

There's indeed a mixture of ages unless we are talking a tree farm. A tree farm is a mono-culture with trees approximately the same age all growing like Q-tips together.

Old growth trees are fire resistant. The younger ones trees get overshaded and don't grow, or they burn down before they get tall enough. The young trees that do survive, they go on to become the next generation of old growth trees.

(My experience on the subject: extensive time camping & bikepacking in Northwest forests, I've traveled through a several thousand miles of northwest forests in the last 10 years)

Why would you be skeptical of tree farming leading to less carbon sequestering?

The whole point of farming timber is to harvest wood which is lignin and cellulose aka CARBON.

The green leaves on the tree are not what will store carbon. The green will fall off and become forest duff which gets digested by fungi and bugs and the carbon released back to the atmosphere.

Goal of timber companies == make more timber timber == captured carbon

Only if the timber gets used long-term. I would argue that a lot of timber doesn't get sequestered for more than a few decades because people tear down old houses and build more density in their place on those time scales. And then that old timber ends up in the landfill.

It's even worse for flooring, trim and casing because people rip and replace those constantly over their lifetime because it's all cheap whitewood or MDF now unless you explicitly pay for hardwood.

> And then that old timber ends up in the landfill.

Timber often doesn't breakdown in landfills due to the level of compaction

I am skeptical of most "more trees" approaches simply because it's not really sequestering carbon in the long term unless you carefully bury the wood underground in rot-preventing conditions.

It's like a bathtub where the faucet is pouring out more than the drain can handle, and the "solution" is to throw a bunch of sponges in. Sure, it'll kinda temporarily keep the water level down, but at some point...

I appreciate the questions and retort. I somewhat agree, but I think when considering a larger context - it changes the equations.

> Why would you be skeptical of tree farming leading to less carbon sequestering?

Two primary reasons:

(1) Comparing a huge old-growth northwest tree that towers a hundred feet in the air, and comparing that to 30 smaller saplings. The amount of carbon stored in one ring of bark of a giant tree like that is immense. The amount of photosynthesis, the amount of total plant metabolism - is immense. This is an anecdotal perspective, but to consider a non-intuitive alternative, there really needs to be some good facts behind it.

(2) The Sinclair quote: “It is difficult to get a man to understand something, when his salary depends on his not understanding it.” There is a extremely strong financial interest for tree farming to be considered as ecologically friendly.

> The whole point of farming timber is to harvest wood which is lignin and cellulose aka CARBON.

I agree.

> The green leaves on the tree are not what will store carbon.

While leaves are not the primary store of carbon, they are still largely made out of carbon. What's more, this is a bit to me like saying "your lungs don't store oxygen."

> The green will fall off and become forest duff which gets digested by fungi and bugs and the carbon released back to the atmosphere.

Forest floors do build up over time. This implies there is still a sequestration effect from this alone.

Bringing it back to my skepticism, the amount of carbon in one ring of an old tree, one that is 6 feet in diameter, the amount of carbon in that one ring is immense. The surface area of leaves is what powers all these other processes.

Say now compared to a group of saplings, where half don't make it and are then chopped down and put into a refuse pile. The saplings that do make it are not adding ring upon ring of bark for a couple hundred years, but only for decades, and in much lesser quantities.

> Goal of timber companies == make more timber timber == captured carbon

The goal of timber companies is to grow tree trunks & cut them down. Does that actually sequester carbon though?

Peer comments point out that building materials are not often recycled and wind up in the atmosphere anyways.

Regardless, the impact of going from a bunch of old and really tall trees that have healthy foliage throughout their entire vertical density - to then go to something like a grove of saplings or a grove of Q-tip like tree farm trees that are older - is an immense difference.

First, there is a huge difference in vertical density of foliage. Tree farm trees I call 'Q-tips' because they do not have much vertical density. It's like a grove of bushes that grow tall but never really gain more area for photosynthesis than that. Meanwhile a "natural" forest has trees that are healthy top to bottom. It's very akin to the micro-surfaces in the lungs or gut to drastically increase surface area. It's the difference of the surface area of a pine cone to that of a flat circle.

Then the other side of the coin too, groves of saplings are not fire resistant. Tree farms are not fire resistant. At some point the area can no longer withstand fires because it's all saplings and they all burn clean.

Then, yet another side of the coin, how much carbon is needed to cut down the trees and transport them? I don't think I've ever seen the "tree farming is carbon negative" argument actually take those additional footprint aspect into consideration. It's always a purely mathematical argument based on tree trunk size alone (which is what timber companies care about, they do not care about roots, branches, leaves, forest floor soil quality; and all of those aspects are not counted for in the theory of "it's best to grow trees to then bury them"). Which also comes back to the other point - building materials sequester carbon only for so long - while incurring a large cost (many of which seem to be unaccounted for).

I mean if you’re turning carbon into wood and then turning that into buildings that’s good right
If the building would be built anyways using more destructive processes or materials, then perhaps. There’s no guarantee that the building would have been built though. Sure most would probably be built anyways, but at some point the different costs would affect the supply and demand at a macro level.

Nonetheless, it’s ignoring the entire carbon-sequestration system that the tree enables. What percentage of buildings are a net carbon-sink (including construction, use, maintenance and eventual demolition), or improve the naturally occurring carbon-sequestration process by merely existing? Any? I really don’t know. It’d be cool if we were constructing such buildings, but I doubt they’d be as efficient as just leaving old growth forests alone.

> They do argue that the tree farm is actually better because it is growing. I'm extremely skeptical of that claim.

One could measure the tonnage of tree farm wood extracted per day against the estimated tonnage of the trees in a non-farm environment pretty easily I would think.

Frankly, the claim, to me, seems incredibly intuitive and your skepticism sounds like stubborn environmentalist thought.

I don't agree with this claim. It is only intuitive on the surface. But growth in trees does not slow down as they get older. It actually accelerates. This article corroborates that: https://www.nature.com/articles/nature12914

Sickness and bad conditions usually slow growth down.

In tree farms almost all the trees are in bad condition. The low biodiversity creates a low quality environment. They catch fire very easily. It's low quality wood that ends up in a landfill (and then in the air via rotting) within a few decades.

Eventually a tree will get sick and die. The most ideal situation would be to harvest the tree when it's dead. I would think there could be a businessmodel that maps dead trees and extracts them from forrests for high quality old growth wood.

This is not about "stubborn environmentalism". Although I do agree with you that some environmentalist ideas are a bit short sighted (like dismissing all nuclear options without weighing the properly), it is generally based in science and research. The anti-environmentalist side are usually mostly based in money and corporate interests...

> One could measure the tonnage of tree farm wood extracted per day against the estimated tonnage of the trees in a non-farm environment pretty easily I would think.

Old growth has a far deeper and broader root system which is a relatively permanent and ever increasing store of carbon in relation to farmed new growth. Roots and stumps of cut new growth are sometimes extracted and used for biofuel, transferring that carbon back to the atmosphere immediately. At best they are left to decompose or converted to mulch and biochar. But the growth process has been halted and no further carbon sequestration will occur. Any further human processing will itself release additional carbon.

Old growth is itself a habitat for other carbon stores. New growth…not really.

Old growth is a habitat for animals which themselves assist in the storage of carbon through indirect means such as pollination and defecation. New growth…not really.

This is just the tip of the iceberg and what I could come up with quickly off the top of my amateur-environmentalist head. It’s complex. A simple estimation of wood tonnage is not going to account for the complexity of the system at all.

> Frankly, the claim, to me, seems incredibly intuitive and your skepticism sounds like stubborn environmentalist thought.

Nice.

Not true frankly. Old growth plateaus from a ton/acre of carbon perspective pretty quickly, and old growth forests aren’t meaningfully sequestering much new carbon in their soil. It reaches a steady state, with excess rotting. Almost no forests do, or they’d be sitting on hundreds of feet of charcoal like matter.

Even the best of them it’s less than 6 feet of carbon containing soil.

New growth pulls carbon out of the atmosphere fast - and cutting it down and using it, gives room for more, fast.

It doesn’t look as nice, and isn’t as pleasant to be around, but the math is clear and easy to verify.

> Old growth plateaus from a ton/acre of carbon perspective pretty quickly, and old growth forests aren’t meaningfully sequestering much new carbon in their soil. It reaches a steady state, with excess rotting. Almost no forests do, or they’d be sitting on hundreds of feet of charcoal like matter. > New growth pulls carbon out of the atmosphere fast - and cutting it down and using it, gives room for more, fast.

Once it reaches this steady state, how much carbon has it already stored? How long will the average undisturbed old growth forest remain at steady state? 200 years, 1000 years? 10000 years? Surely longer than the average lifespan of all the products a destroyed old growth forest might produce. This is especially true when considering that old growth wood is particularly valuable for use as biofuel due to its high carbon density. This means that that carbon will be released far sooner than it otherwise would have, likely magnitudes sooner. And it says nothing of the carbon that doesn't even make it into a product. The simple act of killing the forest and turning over the soil will immediately release carbon.

But, you might say, we'll plant new growth and that'll absorb carbon at a faster rate than ever. Is that rate fast enough to account for the early release of the old growth carbon? How many cycles will it take to recapture that carbon?

> Even the best of them it’s less than 6 feet of carbon containing soil.

So? Is that an average for old growth forest soil? How does it compare to new growth soil average? A single measurement is meaningless here.

More importantly, what is the comparitive density of the carbon in the soil? Depth of carbon-containing soil without a density doesn't tell me much about the total carbon stored.

> the math is clear and easy to verify.

If you say so, but unfortunately you didn't provide any math whatsoever. You seem confident though so if you have any sources, then please do share. I did a quick search for various numbers and comparisons and the numbers don't look good for your argument unless you are only comparing the rates at a given moment and ignoring the total sequestered carbon over a suitable time range (there's probably a better description for this...something like average years of sequestration for any given carbon atom during the average lifespan of an undisturbed old growth forest vs the same tract of land cyclically harvested and replanted at a profit-maximing rate over the same time period)

I've shared the sources in other threads. Here are some random ones I found with a few minutes of googling [https://oldgrowthforestecology.org/ecological-values-of-old-...

Most of these products do actually end up sequestering carbon nearly indefinitely, as unless the house or structure burns down, the product ends up in the landfill or remains on site. Unlike forest products on the forest floor, they don't naturally decompose - we protect them to stop that, as a side effect of how we use them.

Because it is usually pretty well protected, and doesn't meaningfully decompose. Even in most (sufficiently old) landfills, you can dig up newspapers from the late 1800's and still read them. When people print things out, the vast majority of them end up shredded (and tossed in the trash), or just tossed in the trash - which ends up landfilling them, etc.

Once landfilled, what decomposition does happen can be mitigated by processing/burning/storing what methane and the like does come off them.

You're confusing carbon storage (as in total retained) with carbon flux (as in net amounts in/out). Something that old growth folks intentionally also do (first link), near as I can tell, to specifically confuse the issue. If you read carefully you can see them stepping around the issue in the first link I pointed you too.

TOTAL carbon starts to plateau relatively quickly, even as noted by old growth proponents - with total carbon flux dropping and eventually being roughly at equilibrium - usually well before we even consider a forest 'old growth'. If you look at the charts in the second link, you can see the actual curve.

Peak flux (as in total negative carbon) is usually at around 15-20 years.

I'm not proposing we cut down all old growth forests. That would be ugly and counterproductive.

Rather that making a forest that has already been cut down be untouched until it becomes old growth is not the most efficient way to reduce carbon, if we're trying to use forests as carbon sinks.

Be aware however, I've done the math before and even if we turn ALL potentially forestable AND farmable land into forests, it is impossible to sink all the carbon we're currently emitting into forests. Not even close, unfortunately.

But if land has already been harvested (which most has), the more efficient way to reduce carbon is a decent amount of turnover where the products end up going into either durable goods, or landfilled products.

I love trees, and spend a lot of time in nature. I've also done the research, and looked at the reality in front of me, and it's hard to ignore.

> Frankly, the claim, to me, seems incredibly intuitive and your skepticism sounds like stubborn environmentalist thought.

I've travelled along lots of tree farms, on foot and on bike. That is good time to really inspect them. I've also done the same in places that have had healthy burns, California style burns where nothing remains, and have also travelled to some truly majestic red wood groves in California.

A tree farm is a grove of Q-tip like trees where there is darkness underneath and thick nasty underbrush. The 'healthy' forests have trees that are healthy from top to bottom. The Q-tip trees are not healthy, they are too close together.

> One could measure the tonnage of tree farm wood extracted per day against the estimated tonnage of the trees in a non-farm environment pretty easily I would think.

I like the direction of thinking here, namely to try and quantify the effects.

Considering tree farms are left to grow for (AFAIK 40 to 60 years), the "daily harvest" rate needs normalization to account for that growth time (and that needs to be compared against what would happen had those been mature trees instead).

First perspective, plant metabolism. Why do plants use photosynthesis? Namely, to extract carbon so that they can grow. The overall rate of photosynthesis is thus related to the overall rate of carbon uptake. If we then consider the amount of green surface area per square foot (being very careful to consider that healthy trees have immense vertical depth to them) - the photosynthesizing surface area of an old tree is magnitudes more than that of a sapling and much more than a tree farm tree. The area of photosynthesizing surfaces is very important, that's all pulling carbon out of the atmosphere, it's used by the plant. Do plants grow extra leaves for those leaves to do nothing, or for that carbon to be extra?

Thus, area for photosynthesis is a proxy for plant metabolism & carbon uptake. Comparing the total green surface area of a tree farm vs a forest is drastically different. Tree farm trees do not have a depth of canopy. Young saplings have many, many fewer leaves.

So, by one measure, the total area of photosynthesis is very different. How can carbon sequestration be greater for small trees that are incapable of even pulling down the same magnitude of carbon compared to a taller tree that has magnitudes more leaves and surface area?

Thus, the first argument is one purely based on metabolism. A cat needs about 200 calories a day. An olympic athlete needs anywhere from like 4000 to 7000 calories a day. This is the comparison, the metabolism of a giant tree is just huge, compared to that of a 8 foot tall sapling that has a diameter of 3 inches. It's an olympic athlete vs a mouse.

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Second, let's consider a mathematical argument for just wood material. We need to compare the total tree growth of an old tree compared to an equivalent number of tree farm trees in the same area. So, we're just counting here total bark increase over one year (and we're ignoring roots, and leaves - which are significant). For this, a single ring on the diameter of the trunk is huge. The linear length of a ring of tree bark on a 5 foot diameter tree is much more than the linear length of a dozen 3 inch diameter trees. Then, we also need to consider the linear length of all of the branches. A tree farm tree grows short branches and drops most of them. Trees in 'natural' forests have vertical depth, the branches low on the tree are growing and healthy whereas the tree farm tree is not. Comparing the growth of branches, the old trees will be way more than that of young trees, and/or of any tree farm tree (which have been selected for those that grow few branches - makes them easier to process and cut).

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Thus, skepticism is rooted in:

- I see an immense conflict of interest to speculate that tree farms are more carbon negative than a non-tree farm forest.

- Plant metabolism allows for carbon to pulled out of the atmosphere. Plant metabolism is proxied by photosynthesizing surface area, which is magnitudes more in a non-tree farm tree. The rate at which older trees can pull down carbon is just way more.

- The total volumes (per year) storing carbon in trees is much greater for a larger tree than several small ones. That is all of the growth of the roots, the growth of the trunk and all of the branches. It's like what happens when you add half an inch diameter to a baby compared to half an inch on an adult - the half inch on an adult creates a dramatically bigger volume.

The statistical trees per acre reminds me of:

If the utilitarian state could not see the real, existing forest for the (commercial) trees, if its view of its forests was abstract and partial, it was hardly unique in this respect. Some level of abstraction is necessary for virtually all forms of analysis, and it is not at all surprising that the abstractions of state officials should have reflected the paramount fiscal interests of their employer. The entry under "forest" in Diderot's Encyclopédie is almost exclusively concerned with the utilité publique of forest products and the taxes, revenues, and profits that they can be made to yield. The forest as a habitat disappears and is replaced by the forest as an economic resource to be managed efficiently and profitably. Here, fiscal and commercial logics coincide; they are both resolutely fixed on the bottom line.

“Seeing Like a State” Jaces C. Scott

https://files.libcom.org/files/Seeing%20Like%20a%20State%20-...

"basal area" is the term you need and now i'm curious what is the typical basal area for an old growth stand?
http://talltimbers.org/wp-content/uploads/2014/03/Sloan1998a... I found this, where they do note the number of trees has gone up markedly. They note the critical role of low intensity fire.

I doubt selective logging can replace regular burns, but unfortunately there's a great deal of opposition to doing that. Mostly by people living in those fire-prone areas.

lots of the public are very ignorant about ecologically sound forest management, unfortunately. "save the trees" is an effective emotional argument. i was once one of those people, but then i learned
I spent a couple of years consulting to earthforce.io (they make forest management software)- before I started I thought I understood forestry, boy how wrong I was, how little I knew!

For those interested in learning the basics, this is a pretty good playlist: https://www.youtube.com/playlist?list=PLvOmkebY7k2UP4N_BicWV...

that seems like a cool job! do you think they still hire freelancers? i'm looking for freelance work and i'm very interested in forest management but don't have a forestry degree, i just own some land.
where is the Board of Directors, owners and investors of Earthforce.io declared in public?
Unless it's a public company/non-profit they don't have to make any of this information public in most(all?) US states. Usually all you have to do is make public the name of the company and the registered agent(typically the lawyer you hire to receive legal notices for the company).

They appear to be a private company: https://www.crunchbase.com/organization/earth-force-technolo...

"save the trees" is probably better re-labelled as "save the old growth trees". Would you agree?

Would you consider tree farms as ecologically sound? (I'll note those are intentionally over-planted, homogeneous, and burn like crazy)

Which key facts caused you to change your mind?

> "save the trees" is probably better re-labelled as "save the old growth trees". Would you agree?

yes, we should most certainly protect old growth stands. they are very rare in the forests that i'm familiar with in the US east, and maintaining that ecology overrides any economic benefit gained from cutting the trees, imo. i'm in no way advocating for cutting down old growth stands, my comment was more in response to how we manage the forests that came after we cut the old growth.

> Would you consider tree farms as ecologically sound? (I'll note those are intentionally over-planted, homogeneous, and burn like crazy)

this depends on how the forest is managed. monocultures are bad and diversity is good (though a lot of stands have predominant species, naturally), forests need disturbances (whether through thinning or fire or naturally), etc. but a diverse forest can still be in rough shape. i'm getting at the edge of my knowledge fwiw.

> Which key facts caused you to change your mind?

i bought forest land and learned as much as i could about forest management, so there is too much information to list. i can share books if you're genuinely curious.

A sincere and big thank you for the response! The extra context and nuance are really useful to have.

My reading list is already kinda long, I think that spares you from having to dig out any references :)

My curiosity is perhaps most of what would interest a thru-hiker. I always want to learn more about how forests work, things like "bears would live here" - "these types of edible plants would grow here". If there are any books along those lines that jump to your mind - I would be very interested to add those to my reading list.

Thank you again for your responses!

Instead of "us versus them" statements, I encourage vigorous examination of presuppositions. The urgency of the situation could not be more obvious.

The claim "the public is ignorant" is oft repeated by industry-friendly experts in all levels of academia and government. But the policies of the experts have been an objective disaster in the US West. You appear to promote science that is invalidated in real time.

i get what you're saying, but that's not what i'm saying.

state and national forests are a shared natural resource owned by the public, therefore the public has input over these things, sometimes overriding the science. a lot of the "objective disaster in the US West" is due to these policies that are informed by a public who only wants to save the trees.

i'm talking particularly about non-old growth stands where the forest needs to be thinned, but it hasn't, like in the west. old growth stands are a whole 'nother thing. here is one such example where this old growth debate is happening with public input in vermont: https://vtdigger.org/2024/01/18/logging-versus-old-growth-pl...

It is very difficult to cover all the angles in a few short comments. I disagree that "the public who wants to just save trees" is the responsible party.. it is more complex than that.

>policies that are informed by a public who only wants to save the trees

I can give citations for a dozen extensive studies and workshops, some years in the making, alongside more recent research papers from California academia. The ones I know of mostly originate in the University of California system. Actual policy as implemented is informed by those studies but not dictated by them.

Due to the rule of law, actual policy on the ground in the last forty years is divided in practice by the owners of the lands. In California, most of the "public" forest lands are owned by Federal agencies. The "desire to save the trees" conveniently dovetailed with a Federal obligation to maximize commercial value of National Forest timber. The combination of those two, different, policy groups resulted in what has happened in the last ten years.. that is, overcrowding of trees, disease, massive die-offs, and catastrophic wildfire.

Another crucial point.. the pine trees of the low Sierra and North-Eastern California are not at all in the same category as the Coastal Redwoods, or South Sierra old-growth. yet this discussion here seems to make no distinctions.

> substantially better forest

Why is it better environmentally and ecologically?

Environmentally because more diverse forrests tend to be more robust, depending on their climate (taiga is not very diverse). Tree growth doesn't slow down as trees get older. Their growth accelerates because: they have more foliage to gather sunlight and exchange gasses, everytime they add a growth ring it is a bigger ring than the last one, they grow taller or wider to get more sunlight and gas exchange. There is an optimal size/m² of course. Tree farms have ROIs and efficiency problems, they cannot take advantage of these qualities of forrests. They need straight timber and a payday at some point.

Ecologically because old growth forrests have a much more diverse system with big fungal networks, ecological nooks and crannies, etc. A system takes time to build.