Tree planting: Where can I do it and which type is best? • Hacker News Board

Re: Tree planting: Where can I do it and which type is best?

#81

Post by ars » Wed, Jul 31, 2019, 5:38 PM UTC

Jolter wrote: post #43

TeMPOraL wrote: post #21

Earlier quoted context omitted.

I had a stupid thought yesterday that I need to run numbers on, but I wonder if following would be possible: Allocate some large area of ground for planting fast-growing trees. Dig a large and deep hole in the middle; something like 20 meters in diameter x 500 meters in depth. Let the trees grow; when they're mature, cut them down, throw into the hole, and throw a bunch of dirt (from the mound you made by digging the…

No, because the buried wood would decompose. Decomposing wood releases its stored carbon as carbon dioxide, which will slowly evaporate through the covering dirt. One scheme that actually would work is to convert the wood to coal, then burying it. That could be done without adding any energy by using old-fashioned methods for charcoal burning. https://en.m.wikipedia.org/wiki/Charcoal_burner Because charcoal is chemic…

> No, because the buried wood would decompose.

Only if there is water. Bury it deep enough, or protect it from water (i.e. like a landfill).

Re: Tree planting: Where can I do it and which type is best?

#82

Post by onlyrealcuzzo » Wed, Jul 31, 2019, 5:39 PM UTC

armenarmen wrote: post #75

onlyrealcuzzo wrote: post #69

Earlier quoted context omitted.

I did some math on this, and if all the countries in the advanced world planted fast growing trees alongside all paved and unpaved roads, over 40 years, that could potentially be enough to sequester half of all carbon emitted by humans. Given that carbon has a half life of between 20-200 years, and that we appear to be reaching peak emissions, and that a lot of estimates say our emissions should drop by 70% just give…

Could you share your math somewhere? I’m genuinely interested, and did your calculations take into account lowered cooling costs caused by tree shaded buildings?

It did not. But I think that's a HUGE consideration, as is the potential to reduce particulates in the air dramatically.

Here's a link to the discussion: https://news.ycombinator.com/item?id=20543605 -- on mobile so I can't figure out how to get the comment URL. If you're interested, just go there and search for my username -- onlyrealcuzzo. I'd love a second set of eyes on it. Not sure the math is right.

Re: Tree planting: Where can I do it and which type is best?

#83

Post by jandrese » Wed, Jul 31, 2019, 5:39 PM UTC

onlyrealcuzzo wrote: post #69

hillz wrote: post #34

Earlier quoted context omitted.

If a tree is planted, grows, and then for example is burned down and paved over, that'd be true. But if a tree grows and eventually dies in a forest, it'll be replaced with new trees naturally, cancelling out the CO2 leaked from the tree dying. This C02 can also be stalled by harvesting the tree and using it in some way that stops C02 from being released for a longer time than natural.

I did some math on this, and if all the countries in the advanced world planted fast growing trees alongside all paved and unpaved roads, over 40 years, that could potentially be enough to sequester half of all carbon emitted by humans. Given that carbon has a half life of between 20-200 years, and that we appear to be reaching peak emissions, and that a lot of estimates say our emissions should drop by 70% just give…

I think the OP is saying that most trees you plant now will be dead in 20-200 years and returning their carbon to the atmosphere through natural decay. Trees end up being a temporary solution. A permanent solution basically requires us to bury the carbon back in the ground where we found it in the first place, or in some other form that doesn't decay.

Re: Tree planting: Where can I do it and which type is best?

#84

Post by marcosdumay » Wed, Jul 31, 2019, 5:39 PM UTC

jerkstate wrote: post #18

dx87 wrote: post #14

Earlier quoted context omitted.

There was an article posted recently that said the best way to increase the co2 uptake is by cutting down the fully grown trees and planting new trees. Full grown trees don't absord as much co2 as a tree that is still growing, and the needles that some trees drop make the ground acidic, preventing new trees from growing. The problem is that you have to find something to do with all the wood so the captured co2 doesn'…

I'm not sure if that's true. Based on what I've read, older trees sequester carbon at a higher rate, according to [1]. I would like to see the counter claim. https://www3.epa.gov/climatechange/Downloads/method-calculat... page 8

Trees sequester carbon to the extent that they grow. They do very little of both at the beginning of life, they also stop doing both at some point.

There is a maximum rate somewhere in between, in an age that varies by orders of magnitude for different species. It's pretty meaningless to talk about young or old trees without context, except on that general way in that trees get old at some point.

Re: Tree planting: Where can I do it and which type is best?

#85

Post by ryanmercer » Wed, Jul 31, 2019, 5:39 PM UTC

pvaldes wrote: post #74

dx87 wrote: post #14

Earlier quoted context omitted.

There was an article posted recently that said the best way to increase the co2 uptake is by cutting down the fully grown trees and planting new trees. Full grown trees don't absord as much co2 as a tree that is still growing, and the needles that some trees drop make the ground acidic, preventing new trees from growing. The problem is that you have to find something to do with all the wood so the captured co2 doesn'…

> Full grown trees don't absord as much co2 as a tree that is still growing This does not seem logical. Two cars emit more C02 than one car. Two leaves will absorb more CO2 than one leaf. A 2m young tree will never be able to consum so many CO2 as its older 40m high grandparent with a x10000 mass (mass that must be maintained).

>This does not seem logical. Two cars emit more C02 than one car. Two leaves will absorb more CO2 than one leaf.

Mature trees grow much, much, slower. The wood is (largely) the captured carbon so once a given species reaches a certain maturity, harvesting it for lumber to be used in construction and planting a several year old tree would be the most optimal.

Some actually want to genetically engineer trees that grow much faster to do this (although faster growth generally means softer woods, but simply drying the wood and storing it in mines would buy you many decades to centuries before the bulk of the carbon was re-released).

Re: Tree planting: Where can I do it and which type is best?

#86

Post by wang_li » Wed, Jul 31, 2019, 5:41 PM UTC

tempguy9999 wrote: post #47

aresant wrote: post #36

Earlier quoted context omitted.

No easy way to plot this - planting trees to sequester CO2 may or may not have a net positive impact at scale for a variety of reasons: 1) The timescale is very long - a single tree to drive carbon neutrality is MOST optimistically pegged at 40 - 100 years depending on species. With expanding populations planning or guaranteeing execution on that time scale is limited. AKA it's very unlikely that most efforts, unless…

This got voted down in a hurry. Every point seems valid and robust, so why?

If you look at his further posts, his positions are fabricated worst case scenario. For example he suggests that there is no point in planting trees because you're going to drive there in your SUV and then come home and run your AC. This might be true for some people, but it's not for me as my house doesn't have AC and I don't own an SUV. I car pool or drive a prius to plant trees. Also we're not planting trees in places that are then harvested.

When I see people who are anti-tree planting, I wonder if there is some authoritarian predilections at play and anything that doesn't result in central control or provide some mechanism for rent seeking or corruption is going to get down played.

The reality is that if you go and work with your local land management folks who can give you guidance on the types of trees and where to plant them, then going out and spending a weekend putting fifty trees in the ground, will give you quite a nice reduction for the CO2 emissions necessary to plant them. What's more is trees reproduce on their own. If you get a tree into the ground it will likely produce two additional trees over its lifetime if not more.

Re: Tree planting: Where can I do it and which type is best?

#87

Post by marcosdumay » Wed, Jul 31, 2019, 5:42 PM UTC

0-_-0 wrote: post #35

dx87 wrote: post #14

Earlier quoted context omitted.

There was an article posted recently that said the best way to increase the co2 uptake is by cutting down the fully grown trees and planting new trees. Full grown trees don't absord as much co2 as a tree that is still growing, and the needles that some trees drop make the ground acidic, preventing new trees from growing. The problem is that you have to find something to do with all the wood so the captured co2 doesn'…

> [...] as a tree that is still growing Do trees stop growing?

Not exactly, but they also don't grow boundless (some do, but that's because the meaning of "growth" and "reproduction" mix, for all practical reasons, they become many trees). The growth rate slows down superexponentially at some point.

Re: Tree planting: Where can I do it and which type is best?

#88

Post by jandrese » Wed, Jul 31, 2019, 5:42 PM UTC

thinkingemote wrote: post #59

crispsquirrel wrote: post #8

I really want to start planting trees because this planet needs more trees, it's not a joke or some hippy movement, the consequences are real. I just feel like doing so in the UK is a bureaucratic nightmare. Plus buying trees to plant isn't cheap. I might just start saving up for land and planting trees there if I can.

Trees can grow from seed. Johnny Appleseed was an American myth about a man who planted thousands of apple trees by hand using pips as he walked across the country. Seeds can be extremely low cost. Acorns and conkers can be gathered in their thousands each day in the British autumn.

He's not a myth, he was a real person. Some mythology has been built around him, but he really existed and was quite a character.

Re: Tree planting: Where can I do it and which type is best?

#89

Post by ryanmercer » Wed, Jul 31, 2019, 5:42 PM UTC

TeMPOraL wrote: post #21

dx87 wrote: post #14

Earlier quoted context omitted.

There was an article posted recently that said the best way to increase the co2 uptake is by cutting down the fully grown trees and planting new trees. Full grown trees don't absord as much co2 as a tree that is still growing, and the needles that some trees drop make the ground acidic, preventing new trees from growing. The problem is that you have to find something to do with all the wood so the captured co2 doesn'…

I had a stupid thought yesterday that I need to run numbers on, but I wonder if following would be possible: Allocate some large area of ground for planting fast-growing trees. Dig a large and deep hole in the middle; something like 20 meters in diameter x 500 meters in depth. Let the trees grow; when they're mature, cut them down, throw into the hole, and throw a bunch of dirt (from the mound you made by digging the…

Placing them in arid caves/mines would lock the carbon up much longer.

Re: Tree planting: Where can I do it and which type is best?

#90

Post by exhilaration » Wed, Jul 31, 2019, 5:44 PM UTC

guelo wrote: post #45

dsr_ wrote: post #33

Earlier quoted context omitted.

Which is why you outsource the tree planting to a place that has room for trees -- and it's more efficient because they can grow trees better than you can, anyway. nationalforests.org, the Arbor Day Foundation... there are probably lots of good options.

nationalforests.org does reforesting of recently burned forests which are probably burning more frequently due to climate change. I don't think replacing forests that were alive when you were born should count as offsetting your personal CO2 emissions, if the idea is to have an actual effect it has to be new trees in new forests.

On a related note, today's New York Times has an article about the recent fires in California. Near the end the author states that the 2018 Camp Fire released

...an estimated 3.6 million metric tons of greenhouse gases that, as seems to happen at least once every fire season lately, was more than enough to obliterate the progress made by all of California’s climate-change policies in a typical year.

https://www.nytimes.com/interactive/2019/07/31/magazine/para...