I intentionally picked the favorable numbers as I was expecting even with those it would turn out to be a pretty futile endeavor, even ignoring things like fore

I intentionally picked the favorable numbers as I was expecting even with those it would turn out to be a pretty futile endeavor, even ignoring things like forest fires. And it pretty much is, at least with a billion trees. And for a trillion trees I can not see how this could realistically happen. I would have to plant a tree every three weeks for the next seven and a half years, 125 trees in total, that sounds not too impossible. But once you consider that everyone in your city will have to the same - and every other human on earth - I don't think it would be too long before I would no longer be able to find a spot for the next tree where it interferes with nothing and can grow for a couple of decades.