Scientists in the US have identified the factors that make a tree more likely to perish in a drought, after conducting an exhaustive examination of 33 separate scientific studies of tree mortality involving 475 species and 760,000 individual trees.

The answer they come up with is that the deciding factor is how efficiently trees draw water from the ground to their leaf tips. This is not a surprising conclusion, but scientists don’t trust the obvious: they like to check these things.