I was going to dismiss your comment thinking that it wouldn't be possible to capture the amount of carbon we are emitting with trees alone .. but after running the numbers, trees seem like a pretty decent solution.
I'm picturing a large solar farm powering pumping stations to irrigate a large desert like the Sahara, central Australia, Saudi Arabia, the Gobi, or the American Southwest. Maybe all of them.
If we do nothing, Antarctica has 5.5 million square miles of land which might be available for plant growth soon.
Trees.