system
Given the following post, respond as if you're commenting on Reddit:
human
What ecological effect will planting 20 million trees actually have?

20 million trees does seem like a lot, but is it enough to even make a dent in the amount of CO2 humans are producing?

Is it money well spent to spend $20 million of planting 20 million trees?
gpt
Not until those trees grow significantly, but over 40 years each tree captures around 1ton CO2 or 20 millions ton combined under best conditions. 

Unfortunately we release that much CO2 in around 15 seconds.

At the end, collectively humans spent much more than that for big corporations products in a short time, at least once we will be making a difference, whether small or not.