Many more trees could be planted without encroaching on crop land or urban areas | Hacker News Reader

Many more trees could be planted without encroaching on crop land or urban areas

theguardian.com

194 pointsciconia108 comments

It can actually be better than this still. Cattle can be part of a solution to helping restore arid land where the soil has been destroyed by intensive farming and erosion. Healthy soil stores enormous amounts of biomass (aka carbon). Intensive farming has destroyed enormous amounts of land world-wide and turned it into desert, releasing lots of CO2 into the atmosphere.

This is a reversible process and catlle is part of the solution: https://www.theguardian.com/environment/2011/jul/22/cows-cli...

So, using large herds of cattle to refertilize bits of land that are currently not usable for agriculture would capture enormous amounts of carbon in the soil, restore the water retention capability of arid land, put a stop to large scale erosion of remaining soil, and restore it to productive land that may be used for growing food. Alternatively, once restored, you can sit back and watch the land reforest itself or use planned grazing to keep it as grassland. There's no actual need to manually plant trees; though it does probably speed up the process.

Finally, using cattle to fix land produces lots of nice organic/free range meat in a sustainable way as a side effects. And yes, cow farts have a green house effect but it is offset by the captured CO2 in the restored soil. Healthy soil has lots of biomass.

Is this actually validated?

Living in an area heavily deforested for cattle grazing, the cattle grazed land does not look like a healthy land. The cattle keep all plant life cut right back. Hot sun can easily access the soil drying it out, then when heavy rains come, the top soil all runs off the land.

Land that is left without cattle fares better, land that is actively reforested and trees helped to get established looks infinitely more healthy.

I'm on my phone in the country side with slow internet so I cant look up a link, but if I remember correctly, you should search "Alan Savory TED Talk" on youtube for an introduction to the use of livestock to reclaim land. Essentially, the issue with most livestock grazing is that it does not mimic natural grazing, which is a seasonal, high volume, high density event where the herd moves on and allows the grazed area time to recover.

> Alan Savory TED Talk

I'm no expert, but I would approach this with extreme caution. There are a lot of replies that he is "misleading", "wrong", "dead wrong" etc.

There are also quite a few projects where this has been shown to get results in the real world. Enough that it's probably worth trying to replicate the results. Worst case it fails and you hopefully learn something.

>> Land that is left without cattle fares better

This is not true of North America's grasslands. Pre-contact, tens of millions of bison fed on the grasslands much like cattle do now, with certain differences. Most cattle ranching operations are small so there are a lot of fences, which leads to intense grazing in some areas and relatively little in others.

Grasslands have a symbiotic relationship with grazers. Without regular grazing and lightning-caused fires (indigenous populations also regularly burned large areas to help grazing animals), grasslands tend to progress to either bushy forests or dustbowls.

In fact, the greatest danger to the grasslands of North America is farming.

The effects of having cattle/area constant over time are very different from having it change a lot cyclically. Flora, fauna and soil health will all be a lot better if you rotate a large herd over a large area, as a herd, than if they just roam freely the whole time. With a lot of cattle in a small area for a short time the ground will get chewed up and manure will be quite thoroughly mixed in. Leaving long periods in between this treatment means there’s a strong root system though so if the land isn’t grazed again for a long time it recovers well. The closer you approximate hordes of buffalo, aurochs or wildebeest thundering over the plains the closer you’re going to get to savannah/prairie/tundra.

http://www.econtalk.org/moises-velasquez-manoff-on-cows-carb...

> Journalist and author Moises Velasquez-Manoff talks about the role of dirt in fighting climate change with EconTalk host Russ Roberts. Velasquez-Manoff explains how changes in farming can allow dirt and plants to absorb carbon and potentially reduce climate change.

Overgrazing will ruin the land, and will counteract/nullify the benefits compared to well-managed grazing, and it's a no-brainer that further deforestation is a bad thing regardless of what we are using the land for afterwards.

Healthy grazed pasture can sequester carbon, but ultimately we need to let a lot of land go back into natural forest to address the scale of th problem.

Source: “The Carbon Farming Solution”

It can actually be better than this still.

Urban forestry is also a thing, so we don't actually have to exclude urban environments. We can increase the number of trees within city limits as well.

Some resources:

https://www.fs.fed.us/managing-land/urban-forests/ucf

https://www.americanforests.org/magazine/article/vibrant-cit...

You are correct. Here's another link in support of what I think is highly counter-intuitive to people here:

http://www.dasnr.okstate.edu/Members/donald-stotts-40okstate...

Does this offset the methane produced by cattle?

I'm sorry I don't have a link I'm on mobile, but there have been some studies recently that showed putting seaweed into their diet reduced the methan production by a lot (80% iirc).

How you would manage that with the above plan is beyond me though :-)

Yes; don't have a reference available but healthy soil mostly consists of biomass compared to arid land which is mostly sand. The process of returning arid land back to healthy soil involves a lot of carbon capture in the form of dead plants, bacteria, root systems, fungi, etc. I've heard numbers suggestion this can be 70-80% of the mass and it builds up over time to form deep layers.

Another issue is that N2O forms when urine and manure are mixed; which is common with intensive cattle farming. This happens a lot less when cattle is roaming around and instead this helps fertilize the land and stimulates growth; it's actually good for the land. So, compared to growing cattle indoors and feeding them with the wrong food that is typically also produced using intensive farming, there's a big difference.

Related: A Toyota engineer grows forests: https://fellowsblog.ted.com/how-to-grow-a-forest-really-real...

The cool thing is that you can order your own dense, self-sustaining forest from https://www.afforestt.com — and it doesn't have to be big (100 square meters), and it doesn't take a hundred years, either.

Afforestt was started by the Toyota engineer in OPs citation.

But this is very costly.

100 square meters is very, very big unless you are almost unthinkably wealthy. Or at least it is in my neck of the woods.

10 meters by 10 meters is very, very big?

100 m2 is only a square about 33 feet on a side. Big if you live in a high rise in a city but you don't need to be unthinkably wealthy in any area that has woods. The plot of land that my house sits on is 800 m2 and I am most certainly not wealthy, let alone unthinkably so.

The key phrase of the article:

“Without freeing up the billions of hectares we use to produce meat and milk, this ambition is not realisable,”

This is the polar opposite of what is happening at the moment. In particular: https://edition.cnn.com/2019/07/02/americas/amazon-brazil-bo...

Why do you cut of the second part of this sentence?

“Restoring trees at [low] density is not mutually exclusive with grazing. In fact many studies suggest sheep and cattle do better if there are a few trees in the field.”

Because it is not that relevant, for two reasons:

1. Most land used to produce meat and milk is actually not by grazing.

2. I was tunnel-visioned on the part I added. The article calls for reforesting 1.7G hectares, at average 50% density, for a total of 850M. Amazon is being deforested at about 500k-1M hectares per year[1] and the political climate suggests making it worse rather than better. According to a quick googling, over half of Amazons trees are over 300 years old and the deforestation is done with fire, effectively instantly undoing 300 years of sequestration. So, within 3-6 years of business as usual just the Amazon deforestation balances out a year of this theoretically possible global effort.

Please prove me wrong, I don't want this to be true :(

Edit: TFA calls for 1.7G (not T) hectares with 1.2T trees.

[1]:https://news.mongabay.com/2019/05/new-report-examines-driver...

>> Most land used to produce meat and milk is actually not by grazing.

That's false. All cattle is grazed before spending the final few weeks of life in feedlots (unless it's grass-finished beef, in which case the feedlot is skipped).

Anti-cattle people really need to visit a ranch sometime to see what actually happens there because I read a lot of misinformation on HN around this topic.

Separate news touching on this: https://phys.org/news/2019-07-moist-tropical-forests-boost-c...

Note that opportunity claimed here is smaller than the loss from the other source. In my sparsely informed understanding, it seems slowing down deforestation should be our priority #1.

Confusing. The rest of the article is like the second half. Not sure what the first half is doing there. Was that what they previously thought?

You can plant trees at $USD0.10 per tree at trees.org

That's really interesting.

According to this [1], a 10 years old `Calliandra calothyrsus` such as the ones they (trees.org) plant captures about 170 kg / 380 lbs of CO2.

According to the World Bank [2], the average European citizen produces 6 tons of CO2 while the average American produces about 16 tons.

That would mean that they can offset the yearly CO2 emissions of an European or American person by planting 35 ($3.5) or 95 ($9.5) trees, respectively. Quite impressive if true.

[1] http://www.unm.edu/~jbrink/365/Documents/Calculating_tree_ca...

[2] https://data.worldbank.org/indicator/EN.ATM.CO2E.PC?location...

That's true but only half the picture: every time one of these trees dies it is cut down it needs to be buried or otherwise prevented from releasing the CO2 back into the atmosphere. The tree you mentioned is described on Wikipedia as follows: "...This tree grows to about 6 m and has pinnate compound leaves and flowers with a boss of prominent reddish-purple stamens. It is not very drought-tolerant and the above-ground parts are short-lived but the roots regularly resprout..." So that's a significant amount of stuff to bury/dispose of. (The project at trees.org seems very interesting regardless, though.)

Trees don't completely return to atmospheric co2; leaf litter, fallen branches and trunks are an important part of lifecycles for many fungi, bacteria and insects. I goodly amount of said material becomes new topsoil, rather than simply being respirated back out into the air.

We could get back to timber-frame buildings I suppose. If nothing else, woodworking is great fun.

I wonder if anyone is researching genetically modified trees that specialize in carbon sequestration. Sort of like Golden Rice but for climate change.

I wonder that too. Also, how much concrete construction could be replaced with engineered wood construction so that less concrete was manufactured (thus reducing a primary source of CO2 output) and more CO2 could be sequestered in buildings? i.e. can we genetically engineer a tree that grows fast and is well suited for construction uses?

There may be no need to genetically engineer trees for construction at this point, at least not in north america. Some kind of beetle (or was it a fungus?) has killed off a mind boggling number of trees which can be used as engineered wood in construction. As CLT and maybe Brettstapel.

> Some kind of beetle (or was it a fungus?) has killed off a mind boggling number of trees

which may be a side-effect of fighting forest fires and the campaign against logging. higher tree density == easier for fungus to spread. this is why I don't automatically believe anything from the "enlightened" progressive camp. back in the 80's, it was "Stop the Big Bad Loggers! Save the Forest!". Now, had they responsibly thinned the forest, used the timber for logging, that CO2 would be sequestered in homes and the fungus wouldn't have spread through the forest.

I get the premise of thinning, but nature seemed to do just fine for quite some time before humans brought their theories on how to maintain forests. Man comes up with a theory on how to use the land, but then has to come up with new theories to undo the effect the preceding theory caused. Looking at how nature has coped with out humans in Chernobyl is a good example of nature not needing man's help.

I agree that nature doesn't need our help. I'm just saying that there is a demand for lumber. So thinning should be done to satiate the demand, which would thereby put the forest back to its natural state (where wildfires could not reach the trees but frequently burned underbrush and fertilized the soil). Instead we let perfectly good timber rot and spread fungus because thats somehow more "eco-friendly" than selling it to responsible logging companies.

I don't understand why eco-friendly is between scare quotes here. It's not a big leap to see that leaving a forest to manage itself is the friendliest option. Yes, you are correct that wood can be converted to money and if we must do that we should do so responsibly.

Even given that that is the case, I fail to see how that connects to your obvious disdain for the stance that maybe money isn't the most important thing here.

The huge tree die offs in the US have been from invasive species. A big recent one is the Emerald Ash Borer.

Lack of evolved resistance and predators are the key factors.

how does firefighting play into that? there was no firefighting before the 20th century. now everytime there's smoke it's squashed immediately. that cannot be natural.

Is it, though? There have been fires in the arctic for weeks (month?) which haven't been put out. I'm sure firefighters try to put out forest fires asap when they're near human settlements but the world is a big place, and there presumably aren't enough firemen to put out every forest fire.

Before the 20th century, there were likely fewer campers setting trash on fire in the middle of a super dry forest. Or maybe not, come to think of it.

Firefighting is basically not a factor. Insects can spread pretty far, carry some across the ocean and they'll go investigate the opportunity.

Creating plants that have unprecedented attributes is begging for plant diseases to develop with unprecedented attributes. We can't even deal with our own diseases yet, its no time to be testing supercharged lifeforms on the natural environment.

We are already lucky to have trees that grow fast enough and are well suited for construction uses. We are lucky to have sun and wind strong enough replace our unsustainable power sources. We're even lucky we didn't wipe out the ozone layer a few decades ago - only a chance of chemistry gave us enough time to respond.

The global climate and ecological crisis should be a wake up call to appreciate the vulnerability and suitability of the web of life that evolved us, not a mandate for ever more bold experiments on it.

I wonder how much more CO2 can be captured by rapidly growing plants such as hemp or corn? I've also heard that algae is really good at it too.

Don't kelp forests also play a big role in marine carbon sequestration?

Interesting – we need more of such studies.

Check out Drawdown [0] for other interventions with quantified costs/benefits.

Economists widely agree that carbon pricing is the most effective way to fix climate change [1], and fee-and-dividend implementations are the most viable politically (there's a bill before Congress now [2]).

[0] https://www.drawdown.org/

[1] https://www.nytimes.com/2018/10/08/business/economic-science...

[2] https://citizensclimatelobby.org/energy-innovation-and-carbo...

> Economists widely agree that carbon pricing is the most effective way to fix climate change

That is true, and does not conflict with the findings of the article.

I think the difference here is that we can start planting trees right now. Carbon taxation is something people still pretend doesn't have to be done.

It's also worth noting, that given the accelerating pace of the climate crisis, the time to start planting those forests is NOW. Not in a year, not in two years, NOW.

Absolutely true. And tree planting appears (to me) to be an underappreciated philanthropic cause area. This study could help change that.

Most people are overestimating the value in planting trees.

Trees readily plant themselves in areas they are well adapted to. Areas that don’t quickly turn into forests are generally poorly suited to growing trees.

Further, not all trees are equivalent with marginal areas generally resulting in small and often very slowly growing trees.

> Trees readily plant themselves in areas they are well adapted to.

I am very skeptical if that's true – see formerly forested areas like Iceland, Brazil, etc. It's not easy for a single sapling to grow into a tree, even if the conditions are right. That's why companies like Afforestt exist [0].

[0] http://www.afforestt.com/

Trees don't disperse their seeds an unlimited distance. But, if you look at a map of where they want to plant new trees you will find many trees already in those areas.

Edit, back to your point. Forest fires and other natural events regularly kill off large chunks of trees. They need to be able to grow in those areas in order to survive.

> Trees readily plant themselves in areas they are well adapted to.

We're at a point where passively going with "let nature take its course" is not a prudent action. We need to nudge things where and when we can. There's multiple documented instances of forests being replanted, so this is not idle speculation.

Yes, over hundreds of years. I have a few acres of land and there's several trees on ~.5 acres. There's some young trees in the ground spreading from the original half acre that got there naturally. They're a good 4-5 feet from the original tree.

It'll take a while to get the rest forested if I wait, though squirrels and birds moving seeds could help. Part of it is that trees can make the area better for other trees; the conifers stop grass from growing under them, which is good since the grass can be as tall as I am and block out light.

> Areas that don’t quickly turn into forests are generally poorly suited to growing trees.

For some value of "quick", you are correct. Fertile land will indeed eventually develop into some kind of forest absent factors that inhibit such development (such as grazing cattle). I do not agree with you about this process being quick, as it can easily take more than one human lifetime for this to happen.

By planting trees you can very much speed up this process, but it’s still going to take decades to get significant tree growth. Further, you can’t count 100% of those trees as net growth because the area would have gained a few trees in that same period. So, critically the impact of planting trees needs to be compared to an ever more forested area that would have occurred if similar measures where taken but zero trees planted.

On top of that grasslands can store significant carbon in root systems which is then slowly released as the grasses are killed of by tree growth.

I believe carbon pricing has two aspects - one is to charge carbon emitters, the other aspect is to use that money to do something that reduces existing CO2 levels. Just charging emitters does not completely solve the problem, so research into the best ways to spend the funds generated by carbon pricing is critical.

I always thought that carbon/green certificates taxes go towards environment/renewable energy, but I'm probably too naive...

How to minimize the Tragedy of the commons effect? Where countries don't want to impact their economic growth because other countries won't impose such taxes, therefore some production will move there.

>How to minimize the Tragedy of the commons effect? Where countries don't want to impact their economic growth because other countries won't impose such taxes, therefore some production will move there.

This was the point of the Paris Agreement.

The Paris agreement did nothing about this. It is completely non binding. The actual emissions reduction plans (INDCs) were drafted by each country and not negotiated.

Good question. The answer lies in multilateral agreements (Paris etc.) and in so-called Border Carbon Adjustments. The latter have to be implemented carefully so as not to violate any WTO rules [0], but it's possible.

[0] https://www.brookings.edu/wp-content/uploads/2018/07/TPC_201...

It depends. You could, for example, make high carbon taxes while reducing income taxes or dividending the money back to people. This would let you have more of a carbon blocking effect while keeping government revenues steady.

If you use the money for a specific purpose, then you either need low carbon taxes to avoid radically altering the government’s role in the economy, or you are making a large bet that the government will spend the money well.

Having a large, long run carbon tax will do much to encourage the market to develop alternatives.

I imagine you include deductions, like most tax systems, with actions like planting trees being counted against your emissions. For many businesses that would be a more effective way to spend, and likely more efficient than the government middle man doing the work

Better to start now with some rough combination of redistribution to help the most vulnerable (in society, and to climate impacts), the poorest etc, and also projects to manage and reduce - forestry planting, clean energy, insulating houses not at risk of floods etc.

Then once it's in and working start researching better and more effective ways to use it. I don't think we have the luxury to hang around any more.

Charging emitters absolutely solves the problem by itself!

You just have to charge enough to get emissions down to the desired level.

Really? Economists see economic solution...

> Economists widely agree that carbon pricing is the most effective way to fix climate change

Those economists are basing that claim on two highly questionable premises:

(1) That we know with high confidence that reducing CO2 levels will "fix" climate change. We don't know that. Climate models based on that assumption do not make accurate predictions.

(2) That we know with high confidence the economic consequences of particular interventions such as carbon pricing. We don't know that either. Economists' predictive ability is even worse than that of the climate models.

From the article:

“Crowther emphasised that it remains vital to reverse the current trends of rising greenhouse gas emissions from fossil fuel burning and forest destruction, and bring them down to zero. He said this is needed to stop the climate crisis becoming even worse and because the forest restoration envisaged would take 50-100 years to have its full effect of removing 200bn tonnes of carbon”

200bn tonnes? Apparently humanity releases at the moment almost 40bn CO2 tonnes per year (1). All that trees then replace only 5 years.

1) https://iopscience.iop.org/article/10.1088/1748-9326/aaf303

"CO2 emissions grew by 1.6% in 2017 to 36.2 Gt (billion tonnes), and are expected to grow a further 2.7% in 2018 (range: 1.8%–3.7%) to a record 37.1 ± 2 Gt CO2 (Le Quéré et al 2018b)."

My interpretation:

Only 42 % of the emitted CO2 stays in the atmosphere[1], the rest is soaked up by land and ocean. The article only relates to the CO2 in the atmosphere.

[1] https://www.co2.earth/global-co2-emissions

That factor changes "5 years" to 12. Which is still less than that because our emissions still increase.

I don't suggest that trees aren't important, just that they are definitely still just a tiny part against what we put in the atmosphere at the moment if we contiue to do so (and we do too little to change that).

Where can one donate to an organization that plants trees?

this is one: https://edenprojects.org/

If you know tentree shirts, that's who they donate to.

There are tree planting orgs like https://trees.org/

There are also very effective tree saving charities like "cool earth"

https://www.givingwhatwecan.org/report/cool-earth/

https://trees.org was mentioned elsewhere as well, but when I tried to donate they really asked for a prohibitive amount of personal information. Then they had a "privacy policy" that I had to agree with, which was also chunky. I prefer donating to an organisation that recognises that there is no need for a huge amount of my personal data.

There's also https://www.ecosia.org/ search that donates ad money generated from searches to tree planting projects. They also provide their monthly finances on their blog.

> The analysis found there are 1.7bn hectares of treeless land on which 1.2tn native tree saplings would naturally grow.

> Crowther’s team calculated that there are currently about 3tn trees in the world, which is about half the number that existed before

I really hope this study is solid, but how can 1.2tn re-planted trees make up for a loss of 3tn logged ones? And moreover cover the CO2 of all that burned coal and oil?

Because it's not suggesting to return to pre-human numbers, but to plant without encroaching on current agricultural and urban land.

It's about time this was noticed.

Consider that coal comes from dead trees - growing trees will be a big part of the solution.

Trees that had their leaves stripped by acid rain, flowed into stagnant seas and the nutrients caused ocean-wide algal blooms.

Given the right approach, this is also probably the only way to tackle climate change that is self-sustaining. Because trees reproduce. And they constantly search for ways to adapt to their environment in order to survive and reproduce.

Human technology can't do that yet.

And hopefully not soon.

A glimmer of hope? Waiting for the other shoe to drop in terms of "it will cost too much", "politically it's not possible", or some such...

I think part of the appeal of this plan, aside from its theorized effectiveness, is that it doesn't require any political buy-in. People can plant trees all on their own.

That said, a trillion is a quantity larger than any human has the ability to intuitively grasp. It really depends if by "planting trees" they mean "scattering seeds by aircraft" or if they mean "hand-planting saplings".

Maybe this helps: if most Americans plant 3 trees, that's about a billion trees.

When I was young and part of a crew, each us planted -several hundred- trees over 3 eight-hour days. So at least a thousand per person in 10 days. A nation-wide volunteer org -with access to enough seedlings- ... that's the tricky part ... could quickly multiply that to 300 per American - 10% of that trillion.

"scattering seeds by aircraft"

FWIW, There are startups doing this idea like BioCarbon Engineering https://www.biocarbonengineering.com/services (found via video by one of it's investors Tom Chi https://vimeo.com/294975140 (at 11 minute mark) )

The concept of seed drops / seedballs seemingly goes back to the 'zero budget farming' ideas of Masanobu Fukuoka (an older video that goes into seedball making - https://www.youtube.com/watch?v=A4-bwW8PWI0 )

It won’t matter if we keep pumping carbon dioxide into the air, once the forests are grown, unless we bury them all deep underground and grow them again. It’s a one time thing.

It will definitely matter (and potentially quite a lot). Whether or not it will matter enough to offset every problem is up for debate, but this is tractable and practical and we should therefore be doing it. As well as doing everything else we can do to solve this issue.

Finding ways to get trees to grow in inhospitable areas, like the tundra, deserts, and at high altitude, can also help.

As far as deserts go, here is Geoff Lawton using permaculture to grow fruit and other trees in Wadi Rum, Jordan, a desert that gets just 17mm of rain per year (less than an inch). They use only permaculture and greywater to achieve this feat.

https://www.youtube.com/watch?v=ycLbO02lb7w

If fruit can be grown there, it can be grown almost anywhere on Earth.

        “We still have a net loss of about 10bn trees a year,” Crowther said.

This is a horrible number... I wonder what the true loss is, without the component of planted trees?

"The Planet Now Has More Trees Than It Did 35 Years Ago" (Nature publication):

https://psmag.com/environment/the-planet-now-has-more-trees-...

What do scientists say about alleged negatives about planting trees, like reduced reflectivity and slower disperal of fumes in cities? Do any of them still stand?

That means a global / multinational movement against governments cutting trees (eg for lucrative construction deals) is needed.

Buy a little property and plant some trees, doesnt have to be that expensive. Thats what i did.

Massive reforestation would eventually reduce cost of wood construction, allowing harvesting and replanting to sequester even more carbon.

Cutting for wood doesn't hurt since the carbon is still trapped in the wood. In fact it helps since they regrow new trees that sequester carbon faster in their early years than mature trees.

> since they regrow new trees that sequester carbon faster in their early years than mature trees

Is that actually the case? Wouldn't a larger tree's volume mean it consumes a ton more Carbon than a smaller tree, even if the smaller tree is rapidly growing?

Turns out it's not so simple:

Young trees sequester carbon faster: https://psmag.com/environment/young-trees-suck-up-more-carbo...

Old trees sequester carbon faster: https://theconversation.com/big-old-trees-grow-faster-making...

Though when you consider forestry has the goal of producing sequestered carbon (wood), you would think they'd find a fast way to do that. In my country, commercial forestry is done with non-native species that are planted by the forest owners and obviously must be replanted for them to keep operating. They harvest them after about 20 years of growth. I guess that's the age when further growth would be too slow to be economical.

There's been studies showing the rate of sequestration increases as the tree gets older. So there's a disadvantage when young.

We should find a way to discourage cutting mature forest and rainforest as well as planting new.

That is the superficial thinking but unfortunately it is not true. First when they cut trees, they do not haul in the branches and the leaves. There is no money in that. The branches and the leaves are all cut out and left in place with just the main trunk being hauled to the sawmill. The branches and the leaves then dry out and rot releasing their carbon. This means that big part of the trees mass (probably at least 50%) does not get its carbon sequestered. (For a similar reason freshly logged forests are a much bigger fire danger than forests that have not been logged at all).

Secondly unfortunately, in general loggers mostly do not regrow the areas they cut down. Although they do talk about regrowing whenever they are talking to the media, in reality the areas regrown are far less than the areas cut down and thus the earth is losing a lot of tree cover every year.

Dunno what kind of tree it is, but I do see tree plantations where each was clearly planted at the same time in a grid, and in a race to the sky, the trees don’t bother with outward branches much, just the ever rising canopy.

If carbon offsets are properly modeled, planting and cutting (profit/cost) would work itself out.

I think of how the acid rain stuff seemed to have worked out: https://en.wikipedia.org/wiki/Acid_Rain_Program

So would deciduous trees better than evergreens for this given that they shed tons of leaves every year?

I wonder about growing trees in regions losing permafrost from GW

Perhaps there's a natural negative feedback where a higher CO2 concentration leads to more tree growth which reduces the CO2 concentration.

I wonder about creating a new homeland from reclaimed permafrost for climate refugees from all over the world. Maldives is already saving up for one since 2009 and looking at India, Sri Lanka and Australia.

actually it may be the case that the soil is too poor, or the long winter nights and too short days is too inhibitive.

I know that efforts to reforest Iceland have not been very successful.

even if it worked, could be too slow

What, is it the 1980s again? Save the Rainforest and Plant a Tree? Why did that plank of the environmental movement get dropped? Did it?

In any case, it is back just in time for the latest season of Stranger Things. Ooh!

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