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Comment by roflmaostc | Hacker News Reader

The problem is you cannot plant enough trees around the globe to offset our CO2 emissions. Also, a forest only absorbs CO2 while alive. Once it dies, it emits CO2 too. You would need to permanently store the wood somewhere (submerging in water, etc).

Recent article: https://www.theguardian.com/environment/2025/nov/28/africa-f...

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Planting trees solves both the carbon capture and the emissions issue from different angles. Some examples are:

- With more wood available it’s more economical to use it as a building/manufacturing material over other emissive sources (concrete, steel, plastic)

- We can replant the same area multiple times

- Even if we plant crops for biofuels, it’s closer to carbon neutral than burning fossil anyway

Every move we can make towards planting (and managing) more of the surface of the Earth is an improvement, without waiting for miraculous new technology.

It's possible to permanently capture the carbon if you turn the wood into charcoal and ultimately bury or store that.

But left out to rot and yeah, the fungus and bacteria will ultimately consume the wood and release CO2 as a byproduct.

You don’t need to convert it to coal. Use it to build houses, furniture, and other things.

I am currently building a wooden house this way. Wooden frame, wooden exterior, wooden floors, even wood-based insulation (https://huntonfiber.co.uk/). The isolation has the shortest life span and it is expected to last at least 60 years.

If these forests are planted by humans, why do we think the dead trees would just be left to rot like you suggest vs being harvested for wood? The logic does not compute other than trying to make a ridiculous point.

using the wood for heating also releases the CO2. I do think planting trees is a good idea, but it's worth pointing out they can be a carbon source even after harvesting, depending on the usage.

On the other hand if the wood is used for construction or furniture it will not emit.

I think this loses the forest for the trees. That is, a single tree rotting isn't what matters its how long the ecosystem the tree is part of lasts. Consider a square kilometer of denuded land turned back into a forest. You can think of the forest as a temporary storage for carbon, its stored in the trees, soil, animals, insects, etc in that square kilometer. Individual trees may die but on average if the forest remains in good health there will be a number of tons of carbon kept out of the atmosphere.

What do you think happens to harvested wood?

why do you think it will only be used as fuel? it can also be used to build things with it

I didn't say fuel. It also rots when used as a building material.

Then you’ve built poorly. That’s not the wood’s fault

No? Buildings don't last forever.

No, but when built right, log cabins have lasted 100+ years easily. Furniture has lasted that long as well. If you keep it dry, it will last longer than you, your children, and your grandkids. Easily. At that point it is more forever than you

One little appreciated fact is that trees also respirate CO2 when they are cracking their stored sugars produced via photosynthesis. So they don’t sequester all of the CO2 that they consume.

It's little appreciated since tree growth still consumes CO2

I suppose I’m pointing it out to highlight the trade offs with any of these solutions.

What is unsaid is that we need to sequester CO2 for hundreds of years—often far beyond the lifespan of the trees. Trees are short term storage, and sometimes the storage is a lot shorter than popular imagination purports.

Individual trees are short term storage which is why its important to create healthy ecosystems for them to live in. Turning denuded farmland back into a forest buffers carbon from the atmosphere for as long as the forest stands. It could stay there for centuries or return to the atmosphere if it gets bulldozed for a subdivision.

Biochar seems like a good option

It's a hugely underappreciated option. I'm not sure how accurate it is (or how legitimate the companies doing biochar carbon removal are), but cdr.fyi shows biochar as the top carbon sequestration method that's actually happening.

Trees have advantages that go beyond bureaucratic aspects of environmentalism.

I think that I shall never see a poem lovely as a tree. -- Joyce Kilmer

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