Another reason to worry about global warming: more and itchier poison ivy. [Poison ivy])http://en.wikipedia.org/wiki/Poison_ivy “Wikipedia: in the family Anacardiaceae, is a woody vine that is well-known for its ability to produce urushiol, a skin irritant that causes an agonizing, itching rash for most people”) grows faster and becomes itchier as carbon dioxide levels in the atmosphere rise, researchers said in a new study.

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