Tory Twitter, yesterday.

You can do stupid maths with anything, watch: to kill 120k people with austerity in 10 years, you'd have to kill 12,000 a year, that's 32 a day. Seems implausible, but a UCL report reckons they managed it. https://bmjopen.bmj.com/content/7/11/e017722.full

Or to flip it, if every grown-up in the UK planted 40 trees AT SOME POINT in the next 20 years, we'd be covered. That's two a year…or you could just skip the football this weekend and do it in an afternoon.

To conclude: I'm not a tree expert, but to dismiss an ambitious plan on the basis of being bad at maths is nonsense. Yes, it's a lot of trees. We NEED a lot of trees. We get a lot of other stuff done, why can't we plant a load of trees?