(CNN) -- Every spring, a yellow blanket of pollen descends upon America, eliciting complaints from allergy sufferers already fed up with watery eyes, stuffed-up sinuses and excessive sneezing. If you're wondering exactly what that is covering your car, it's pine pollen, which usually comes out in mid- to late-April. But believe it or not, it's probably not what's causing your symptoms. "Amazingly enough, most people are not allergic to the stuff you can see," CNN meteorologist Sean Morris said. Instead, it's microscopic particles in the spring air that are hell-bent on causing misery. Most seasonal allergies are caused by smaller tree pollen and mold spores, according to the American Academy of Allergy, Asthma & Immunology.
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Most people aren't allergic to the yellow pollen you see, which is from pine trees
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More than 60 million Americans suffer from allergic rhinitis every year
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Warm, dry climates have the highest pollen levels, according to Pollen.com
@placeholder breaks the United States down into seven allergy regions.