[A] winter that warms up too much for too long, causing plants to "think" it’s spring, could be truly disastrous if temperatures revert and freeze again. In the Wölffer vineyards, Pisacano worries about his vines’ fragility as they come out of dormancy; if a freeze hits then, their trunks could split, causing fatal damage. As Dr. Carroll explains, "A spring freeze event is very bad because plants have begun to grow, or their buds have started to swell and are less cold hardy." The line between "rough" and "disaster" on those days is razor thin. In apples, the difference between a frost that causes a 10 percent bud loss and one that loses 90 percent can be under 10 degrees’ difference, held for just a half-hour.
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