A sequoia sempervirens lives 1,500 years.

I am not deluding myself that we will mitigate climate change by covering Earth in sequoia, but still that gives some timescale on how long trees can live.

If we could mitigate climate change for another 1,500 years we would probably have found some other mitigations by then.

I do not see how the maximum age of the trees matters. There is no difference between 10 generations of trees that live for 150 years and one generation that lives for 1500 years. What matters is the amount of additional CO2 which can be bound in biomass per square kilometer (comapred to the biome we are replacing) and how many square kilometers which are available for this project.

I fully support any plan that ends in the forest moon of Endor. What are even the odds we'd have fossil fuels left to burn in 1,500 years? I feel like we can safely say we'd have reached peak oil by then.

I don't know the source other than Elon Musk stated it in one of his presentations, but according to him we have five times as much fossil fuel reserves as we would need to utterly destroy ourselves with climate change. If that's right, waiting until we run out is not a solution. I realize the context was mentioning some speculation that we could push the timeline out some by planting trees. That speculation aside, we can't just wait for the oil to run out and be fine.

I didn't intend argue we should wait until we run empty on Fossil Fuels. I just can't see any way in which we'll still be consuming them in 1,500 years - either we'll have moved off them, we'll have run out, or the world will have become not compatible with life (non-exclusive "or" in this case).

Great comment and even better concept.

It's worth mentioning that sequoia along with a few other species are outliers as far as longevity. Most trees do not live nearly that long.

FTR, many tree species can live for hundreds of thousands of years.

"FTR, many tree species can live for hundreds of thousands of years."

The oldest known tree in the world is 5000 years old.

No individual trees are known to live hundreds of thousands of years.

There are clonal trees, like aspens, that could live as a colony for hundreds of thousands of years, but that's not quite the same thing (and our oldest verified example is only 80k years old).

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

Ok, you're right that it depends on what you count as a tree. An aspen "colony" is a living organism, and its "trees" visible aboveground are merely its stems. Such organisms may live as long as 1,000,000 years.