Why do some trees die in a drought and others don’t? And how can landscape professionals predict where trees are most likely to die in future droughts?

Scientists from the University of California-Davis examined those questions in a study published in the journal Ecology Letters.

Using climate data and aerial tree mortality surveys conducted by the U.S. Forest Service during four years (2012-2015) of extreme drought in California, they found that when a drought hits the region, trees growing in areas that are already dry are most susceptible.

The research also showed that the effects of drought on forests can take years to surface, suggesting that such effects may linger even after a drought has ended.

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