"Doc, I think I'm allergic to cottonwood tree. Every summer I start sneezing my head off when those "cotton things" start floating around in the air."

Every year in May or June a few people ask me about cottonwood allergy after noticing their eye and nasal symptoms escalate as the cottonwood tree molts its seedlings. But this is a common misconception. In March and April (primarily in northern states of America) cottonwood tree pollen fills the air, along with the pollen of many other...