[btilly]

Except, half of all planted trees are dead within 5 years. And my guess is that the easily available planting locations of people planting trees close to them are less likely to survive.

Second, it is rather hard to find a solid source for that CO2 number. https://onetreeplanted.org/blogs/stories/how-much-co2-does-t... supported a figure that is half that one.

Third, CO2 in trees does not necessarily REMAIN in trees. Need I remind you of last summer's wildfire problems? To fix the wildfire problem, we need to remove large amounts of dangerous overgrowth that a century of fire prevention has encouraged.

Fourth, the current trend is towards losing forests, not gaining them. It is easy to point to land and say, "Add forest there." But people living there who want to plant soybeans and raise cattle have different ideas. That's why rainforest is disappearing. What do you wish done with those inconvenient people?

Yeah, planting trees sounds great. But it is not likely to be a workable solution in the real world. Though it has promise as one of many pieces of a workable solution.

[GravityLab]

1. The average tree's lifespan is a lot longer than 5 years. It's more like 300-400 years. I've not seen any sources saying that half of all planted trees are dead within 5 years. Even if that is true, 5 years is enough time to keep replanting and maintaining the total number of trees much higher. People can tend to the trees they plant.

2. I got my number for CO2 capture per tree from the U.S. Department of Agriculture, the Arbor Day Foundation, and the European Environment Agency.

3. I don't think the wildfires materially impact the calculus.

4. There is a lot of land available for reforesting. This is not the same as saying that we should take back land that is used for farming. I would say that agriculture is going to innovate too, with vertical farms and more efficient usage of land where land is still necessary. We can start with land that is already available for reforesting rather than starting with squabbling over land that is now already used as farmland. Making farmland more efficient and innovating with vertical farms will let markets take care of inefficient and unnecessary land usage.

5. Planting trees for CO2 capture is a temporary solution. Eventually machines will sequester CO2 far more efficiently. Planting trees in general is nice for many other benefits too, not just the carbon capture. But yes, planting more trees is not the only thing we need to do.

[btilly]

https://www.earth.com/news/half-of-plants-used-in-reforestat... gives a reference for half of planted trees dead in 5 years.

Your CO2 capture figure is widely quoted, including in those places. But can you find a scientific paper that it goes back to? I'm a little wary of figures that I can't find a real reference for.