There’s Plenty of Space for One Trillion More Trees | Hacker News Reader

There’s Plenty of Space for One Trillion More Trees

nautil.us

156 pointsdnetesn74 comments

So the count of how many trees there are now was off by an order of magnitude.

And we are supposed to give credence to an estimate of how many there were 10,000 years ago? What makes you think that's any more accurate?

This kind of sloppy science is ruining people's confidence in science. I know it's supposed to be an iterative process, always getting better, but there should be some self awareness built in that early iterations should not be relied on in any way!

I'm not able to read the actual research paper, but the article refers to the "United Nations estimates of global forests." I'd assume they used the model they developed for forests and applied it to this estimate to get a number of trees.

My (uninformed) guess is they could make estimates by comparing forrest land and tree density. The former isn't too hard to come up with.

So the article says that there are currently about 3 trillion trees, down from about 6 trillion when humans started with agriculture, and then cites an ecologist about how insane this is. But, if you go back even further, wouldn't there be less trees again? I watched the documentary "The Green Planet" a while ago. If I remember correctly, it said that before humans greatly reduced the number of grazing animals in Europe by hunting, the forests in Europe were not dense like today. They were more like parks, with many grassy fields, since obviously many trees did not get the chance to grow tall before being eaten by those grazing animals.

I am not an expert on this but I assume the total amount of carbon on the earth is essentially constant. I am guessing for the most part it exists on earth as (1) plants and other life forms (2) fossil fuels and (3) other non-living stored carbon, in things like plastics and lumber. In the air it is mainly carbon dioxide. The more we store on earth the less there will be in the air.

Maybe we need a plant and trade system rather than cap and trade. Whenever fossil fuels are sold, a corresponding amount of carbon must be stored, either through new plants of in other sequestered carbon.

You're describing one form of carbon offsets. A cap & trade system is pretty much what you're suggesting, depending on the specific implementation of a cap&trade system.

https://en.wikipedia.org/wiki/Carbon_offset#Land_use.2C_land...

I did not realize cap and trade systems were backed by actual carbon storage. That makes more sense then. Thanks for the link.

they don't have to be.. but most cap and trade proposals include carbon offsets... so a polluter can complete an offset project OR purchase credits to pollute more.

We mostly care about carbon accessible to the atmosphere.

That's carbon directly in the atmosphere, soil and upper layers of the ocean.

The depths of the ocean can take basically arbitrary amounts of extra carbon-dioxide, and if we stopped producing CO_2 now, in about two thousand years (if I remember right) the oceans would have absorbed and `buried' the extra carbon released by human activity.

Of course, during the process the upper layers of the ocean acidify for a while. That's bad, too.

Do not forget rocks!

https://en.wikipedia.org/wiki/Carbon_cycle

Look here: https://www.google.com.au/maps/@-33.0362291,118.4896355,5465...

Can you figure out where there used to be trees ? That's now wheat farms mostly. Due to the tree removal salination has ruined 2 million hectares of what is now essential wasteland. https://en.wikipedia.org/wiki/Salinity_in_Australia

Don't know why you couldn't replant trees then. There are many types trees that do well in saltier soil. For example, White Ash, Red Cedar, Black Walnut, Japanese Black Pine, Pin Oak and Red Oak. Doubt it'd take much to get something estabilshed, and it'd probably take over on it's own gradually.

Not sure that you'd want to plant a bunch of European trees to replace native Australian forests.

Those were examples.

Find the australian equivalent.

Pretty easy to find.

Eucalyptus camaldulensis (River Red Gum) is one that is great in high saline environments.

Eucalyptus leucoxylon (Yellow Gum), Eucalyptus melliodora (Yellow Box), Eucalyptus microcarpa (Grey Box), Eucalyptus ovata (Swamp Gum), Eucalyptus viminalis (Manna Gum), Acacia melanoxylon (Blackwood), Allocasuarina verticillata (Drooping Sheoak) Are all good in medium saline environments.

So have your pick.

Why?

It would be futile. Native Samphire, melaleucas and casuarinas can live in saline soil conditions that would kill most anything non-native. There may be exceptions of course.

Its when the Samphire starts to die that you know your in shit street.

Australia lost large parts of its native wildlife due to things like this.

Or grow an edible halophyte, such as Salicornia.

In the long run, it would probably be wise to introduce a profitable salt-sequestering crop into regular rotations, just to keep marginal lands from becoming unfarmable.

Native Australian trees are the most salt-hardy trees on the planet. The non-native species you listed would most likely not even survive in "normal" Australian soil conditions.

Wow, the way the farms are perfectly cut around the protected regions... I thought that was just tiling in GMaps.

That's horrifying.

Zoom in on just about anywhere in Oregon and you will see a strange halftone pattern. Checkerboard logging.

I think this may have been due to the railroad land grants originally https://en.wikipedia.org/wiki/Checkerboarding_(land)

Interestingly, planting 1 trillion trees all at once would decrease the albedo of the earth (https://en.wikipedia.org/wiki/Albedo), increasing warming in the short term. I wonder how long the trees would have to exist before the scrubbing effect on carbon dioxide would outweigh the albedo change?

The albedo shouldn't decrease with more trees. More trees, more clouds. And clouds are the reason why the earth has such a high albedo.

Geez, albedo is a topic I didn't know existed until just now, but which is clearly a complex enough topic for hundreds of people to spend their entire lives studying it. Super cool.

The fantastic SimEarth had a great daisyworld simulator that illustrated the concept well. You had two species of daisies, light and dark, and their balance had a huge effect on the world.

Of all the Sim games, that's the one I'd most like to see get an update (though "Planet melting? pay $29.99 for in-game carbon credits!" would be an off-putting business model).

It gets even more complicated, because of clouds..

Depends on what the trees are shading? They couldn't be much worse than concrete I imagine...

https://en.wikipedia.org/wiki/Albedo#Terrestrial_albedo

Albedo of a conifer forest is 0.08 to 0.15, albedo of new concrete is 0.55.

The climate change effects of reforestation are addressed later on in the same article: https://en.wikipedia.org/wiki/Albedo#Trees

Of Asphalt it's only 0.4 - 0.12 though (from your link)

0.04

If you planted a tree every second, it would take you 31 thousand ish years to plant them all.

That said, if you had 100k people planting them itd take under a year. Can a machine plant 1 tree per second? Id be interested to learn that

We could do a lot better than planting 1 per second. How about planting 900,000 trees per day via aerial bombardment?

http://www.theguardian.com/uk/1999/sep/02/paulbrown

Thank you so much for posting this, its so nice on a human level to think about turning mine laying tech into tree planting tech.

At the end they mention a planting capacity of 3k square miles per year which is a lot but still small compared to deforestation rates of 46-58k square miles per year.

We plant far more crops like corn every year with machinery. I'm not sure the humans are even necessary, trees are pretty good at planting themselves.

The biggest issue is outcompeting other smaller plants growing in the same place. It takes a long time for an area to naturally become a forest. I believe human intervention with weeding and watering can speed it up significantly. But that's a bigger investment than merely planting them.

In Southern India Project Green Hands ( https://en.m.wikipedia.org/wiki/Project_GreenHands ) has focused on planting trees by hand. On 17th October 2007 they started a tree planting marathon that resulted in 852,587 saplings being planted in 6284 locations across 27 districts in Tamil Nadu by over 256,289 volunteers in just three days - fairly modest average per person but still enough to set a world record.

Planting 1 trillion trees by 2020 would take each of us 7.3 billion planting around 140 trees over the next 4 years.

https://www.indiegogo.com/projects/treerover-a-tree-planting...

Not quite 1/second, but imagine having a bunch of these running around in your neighbourhood.

> 31 thousand

They would start planting themselves after a few decades.

That's an interesting thought. It immediately made me think of some fast moving contraption that buried seeds into the ground. Obvious difficulties would be navigating, and being small while being able to force something into the ground.

There are people who get paid to manually plant trees. They're called Tree planters. Seeds seem more scalable but the industry appears to use saplings. https://www.youtube.com/watch?v=R9wPTwlGGJs

Maybe a drone could complete the two actions instead. 1. Jam rod thing into ground, pull it out, dump dirt 2. Stuff in tree

A guy on Reddit claimed to have planted 1.25mm trees this way: https://www.reddit.com/r/IAmA/comments/24jgsy/ive_planted_12...

Young trees need water until they're established, so I wonder how many little trees actually survive.

You can wrap their bases with a porous bag of hydrated gel--like a yolk sac for saplings.

Logically, it would be best to use industrial processes to factory-assemble a package that results in the lowest cost per established new tree when it is left in the wild with no further maintenance.

Existing tree seeds are cheap and stupid, and limited by the state or the art in tree-seed technology, which is essentially to coax an animal into eating a fruit and crapping out the seed elsewhere in a nice, fertile pile of dung.

Humans can do better, by sprouting the seeds in a controlled, indoor facility, culling any unsuitable saplings, and granting the sapling additional resources that the parent trees could not provide before planting it in a location distant from the parents that is already known to be suitable for the adult tree.

~Alternately, leave Robo on tree-planting detail, and skip ahead 1000 years in the Epoch to pick him up.~

I can't tell if you're joking or not. The answer is a f'n bird.

Creating tons of birds is not a solution.

I read that the great plains were naturally forests, not grasslands. The theory is they are grasslands because long ago the forests were burned to provide habitat for the buffalo.

This theory is supported by the Kansas farmers having planted trees, and the trees do quite well.

I would imagine that a great deal of forest could be created by replanting the great plains.

You may be remembering incorrectly, the great plains were grasslands many millions of years before humans arrived on the scene. Remember we only left Africa ~100,000 years ago.

Yeah the grasslands are 25 million years old. Humans have only been in America for 15,000 years:

https://en.wikipedia.org/wiki/Great_Plains#Paleontology

The buffalos themselves might have kept the trees at bay by eating young shoots. (Grass is one of the most hardy things to survive grazing. Most other plant species can't stand it in the long run.)

I wonder how that would affect tornado occurrences

I'm reminded of Anna Karenina

> "I wouldn't attempt to teach you what you write about in your office," said he, "and if need arose, I should come to you to ask about it. But you're so positive you know all the lore of the forest. It's difficult. Have you counted the trees?"

> "How count the trees?" said Stepan Arkadyevitch, laughing, still trying to draw his friend out of his ill-temper. "Count the sands of the sea, number the stars. Some higher power might do it."

> "Oh, well, the higher power of Ryabinin can. Not a single merchant ever buys a forest without counting the trees, unless they get it given them for nothing, as you're doing now.

An article here a couple of weeks ago claimed that sea weed is more effective than tree fighting carbon dioxide, and it seems cheaper to plant and manage... Shouldn't we focus on it instead of trees ?

I wonder which would be more effective at countering ocean acidification, since sea plants need the carbon dioxide in the water in order to create oxygen.

While I've been a bit skeptical on global warming, if we decide carbon in the atmosphere needs to be dealt with then we should probably put a price per ton on it and deal with it by whichever methods are cheapest. I'm supposedly financing the removal many tons by donating to Trees for the Future and it's crazy cheap. Something like $100 for 50 tons per year. And that's for the life of the trees so something like 10c/ton.

Let a thousand flowers bloom, and all that.

I really think the answer is to switch to wood fuled biomass generators for electricity. It would be an incentive to plant more trees, and the charcoal waste could be burried as fertilizer, placing excess carbon back in the ground.

The amount of solid carbon left as waste is inversely proportional to how efficiently the wood is burned. In high-heat combustion, virtually all of the carbon is consumed and released as CO2, rather than remaining in the ashes.

What if it were purposely inefficient, and stopped once the wood is reduced to charcoal?

So we basically go back to using fireplaces for heat.

No. The idea would be to never actually burn the wood, just heat it up enough to release gases, and burn the gases in a generator. These could be (are?) run at power plants.

willismichael pointed out that efficient biomass gasifiers will then burn the resulting charcoal, which releases quite a bit of CO2. I suggested using the charcoal as fertilizer, instead of burning it.

Wouldn't heating it up to release the gas use more energy than results from burning the gas?

As far as I understand it once you get it going you can use the gas to keep the temperature up, and still have excess. Of course, this is only until the fuel runs out.

Could satellite/drone imagery with computer vision could get an accurate count?

Given half the trees are already gone, not sure how useful a more detailed count would offer.

Actually there are more trees in the US now than in the 1800s [1]. However, the downside is that there is relatively little age difference in them, since they were planted in the last 50 years or more. This means less diversity of habitat, and it takes a while for the critters to build up biosystems in them. Still, I'll take the positive away from it. The quick effect of actually warming the Earth was surprising to me, because if we plant so many new trees we lower the albedo, and it takes a while for the trees to scrub the CO2 to make it a net win.

  [1] http://www.greenoptimistic.com/united-states-trees/#.VwxsqybSqHs

Maybe we should just plant hemp, the most useful plant on this planet.

I don't understand the argument. We needed to know how many trees there are to know whether we physically have space available for more?

We need to know the density of trees in various environments to understand how many more we can plant. And when you have that, you also know how many trees already exist.

It's also useful to know how many trees have been lost to development, which is closely related to how many currently exist. And all of that is based on knowledge of tree density in various environments.

Attempting to count the trees provided a better understanding of what types of trees growth where with what density, though I would agree it seems like "just go plant some trees" might get more done.

10^12 trees for anyone wondering

Makes little sense because trees die and decay, releasing their stored carbon. We released the carbon from liquid fuels and thats how we should reset, back to liquid carbon that wont go anywhere.

Isn't that how ecosystem should work? Tree dies, new one grows on the spot. X amount of carbon should be locked in a Forrest ecosystem as long as it lives; trees, other vegetation and organisms. Some of it will eventually fossilize for good.

Apparently dead forests release less carbon into the atmosphere than expected:

"Overall, we discovered that after a tree die-off, the loss of carbon in the soil results less from increased respiration by microbes but more from the fact that trees are no longer sequestering photosynthesized carbon into the soil," Moore said. "There seems to be a dampening of the carbon cycle rather than a big pulse of carbon release. So even if the forest now goes from a sink to a source of carbon dioxide, it's not as dramatic of an effect as we thought it would be."

https://uanews.arizona.edu/story/dead-forests-release-less-c...

Trees replace themselves, so the decomposition is balanced by new growth. So even if decomposition releases all of a tree's carbon, adding a trillion trees would take a large amount of carbon out of the atmosphere.

Not sure why this was down voted without a lot of explanation... In theory it makes sense, and it's not like we couldn't do both.

Still if you have an extra 1Tn then that's 1Tn trees less carbon in the atmosphere. The dead trees can also be made into timber, biochar and similar.

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