Climate change could be part of the problem. As Iowa’s winters warm, its growing season is getting longer. That means more days that plant allergens are producing pollen — and more days that people ...

A wave of oak pollen is driving one of the worst stretches of allergy season in Louisiana. Here’s what’s behind it, how long it will last and how to find relief.

Oak pollen levels across Texas are set to rise over the next few days, reaching some of the highest counts of the season so far.