Although climate skeptics might find it hard to believe with this year’s endless snow and freezing temperatures, climate change is making warm, sunny early springs increasingly common. And that affects when trees start to leaf out. But how much? In a study published in Methods in Ecology and Evolution, Simon Joly, biology professor at Université de Montréal and Elizabeth Wolkovich, an ecology professor at University of British Columbia, showed that a plant’s genetics can be used to produce more accurate predictions of when its leaves will burst bud in spring.