Last summer’s derecho was definitely an ill wind, but maybe it had an upside. The leafy greens of spring seem greener and lusher. An unexpected gift from the derecho? “There could be some truth to that," says the city arborist, Erik Dihle. "For example, if some limbs are lost, the trees will sprout and come out with additional flush of new growth between the break and where a branch is broken off. Trees have hormones just like people do, and the hormonal system will signal to the growing points of the trees to flush out with new growth,” he says.