Things grow very well in the Arizona desert when they're watered. Lots of sunlight!

You're right that trees cannot be 100% of the solution. But they can be a big part of it.

> you think 25 years is enough to store CO2 in?

It's starting to rot at 25 years, lying in the rain and mud and beetles. There are logs much much older than that lying around the local woods. There are stumps over a century old. My house is 25 years old, and the wood structure that has been kept dry has no rot at all. None. Zero. Simply by keeping it dry.