This storyoriginally appeared on Gristand is part of theClimate Deskcollaboration. Chris Sayer pushed his way through avocado branches and grasped a denuded limb. It was stained black, as if someone had ladled tar over its bark. In February, the temperature had dropped below freezing for three hours, killing the limb. The thick leaves had shriveled and fallen away, exposing the green avocados, which then burned in the sun.

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