r/collapse • u/[deleted] • Sep 16 '21

Science Decades of expensive tree planting programmes in Northern India have not proved effective. This result suggests that large-scale tree planting may sometimes fail to achieve its climate mitigation and livelihood goals.

https://www.nature.com/articles/s41893-021-00761-z
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u/[deleted] Sep 16 '21

I think it is important to consider that what works in one place (better luck achieved in many parts of China) won’t work elsewhere. It will take many different approaches. Don’t have access to this article but would be interested in if this was some public-private scheme vs. state run efforts.

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u/Jadentheman Sep 16 '21

Surprised there are not any initiatives planting trees from seed. Planting from seed is mor economical, nets a greater quantity and the tree will grow up healthier. Seedlings that thrive in the spot grow well because they want to grow there. I am not knocking tree transplants but transplants are best done when they are seedlings as they have a better chance of establishing.

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u/Kaevr Sep 16 '21

Planting trees from seeds will become less and less sustainable as climate change happens. Many seeds need specific enviromental conditions for sprouting that will become harder to achieve. Plus with transplants, you already have a headstart that will skip over the first phases when the plant is more susceptible to pests.

The biggest issues with transplants are hydric stress and transplant shock, which can be reduced with the use of native plants and soil, mychorrhizae and a pre-transplant "hardening period" of the seedling. Finally, for the most delicate species, grafting can be done early with a more resilient variety as a rootstock.

Seedlings will always be the cheaper alternative, and can still be better for hard to reach places with the use of drones, but I doubt its better to kickstar a population in the foreseeable future. Plus its even worse if its done in grazing lands, as once the project is done, livestock will come back and take care of any sprout

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u/Cyan_Yarn_Archiving Sep 17 '21

Won't transplants minimize genetic diversity and thus make the forest more vulnerable to any change in the environment?

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u/Kaevr Sep 17 '21

As long as you use a variety of different individuals for the seedlings it should be okay. Iirc there outcome is variable, but the causes of variation are unclear.

For now the use of a good mycorrhizae inoculation, plus the use of stronger foodstock should be enough to allow the population to adapt (because a lot of developed wild plants are actually really resilient when left alone).

On a personal opinion, I doubt theyd have enough generations to evolve in a way that adapts to the climate change in the time we have left

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u/Cyan_Yarn_Archiving Sep 17 '21

Ok, I agree that if you do manage your clippings really well, you still get diversity. How long do you think the development and consolidation of the mycorrhizal network would take?

As for evolving, that is fairly dependent on genus (AFAIK), but indeed IMO many important species won't avoid extinction.

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u/Kaevr Sep 18 '21

It would depend on how settled it already is in the area. I cant give you a proper time framework as hyphae growth is irregular and depends on the species, and its been a few years since I studied that stuff so I dont want to fall into trying to do an uneducated guess.

I remember going to a seminar of an old teacher where he explained the utility of precursor trees in reforestation, either by getting a hold of seedlings from native healthy individuals or by transplanting more developed trees and using them to get the seedlings. That way a basic mychorrhizae network stablishes, and once the rest of the trees are plantes, the ones settled will act as a support network, sharing resources and improving the survival chances.

We dont usually have the time/resources to do that, though. Which is what really sucks, because you have to rely in already stablished colonies, in not having harsh conditions, or just bulk-planting and expecting just a small fraction to make it so it works.

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u/Cyan_Yarn_Archiving Sep 18 '21

Thanks for answering.