Early Spring Sets Much of U.S. Awash in Color and Pollen Dust - Pittsburgh Post-Gazette

http://www.post-gazette.com/stories/news/us/early-spring-sets-much-of-us-awash-in-color-and-pollen-dust-627485/?p=0
ATLANTA -- Spring, with its promise of flip-flops and daffodils, can have a dark side. Take this one, which hit so early in many parts of the nation that the headaches are outweighing the sunny benefits.
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Can we see a complete list of the benefits and headaches that were considered before arriving at this conclusion?