What are pollen allergies?

Feb. 22, 2022  Rebecca Rosenberger MMSc, PA-C 

Rebecca Rosenberger is the Associate Director of U.S. Clinical Affairs & Education in the Immunodiagnostics Division at Thermo Fisher Scientific and a physician assistant specializing in allergy & immunology.

If you sneeze, cough, have a runny nose, or experience other common allergy symptoms during peak pollen seasons, such as spring months, you’re not alone. More than 67 million people suffer from allergies, and of them, 81 percent report having a pollen allergy.1 In fact, pollen is one of the most common allergens in the United States.

So what is pollen, exactly?

In technical terms, it’s the male fertilizing agent of flowering plants, trees, grasses, and weeds.2 In nontechnical terms, it’s the yellow powdery stuff that coats your car during spring.

Due to pollen’s microscopic size, it travels easily through the air, especially on windy days. This means that your allergic reaction might not be caused by pollen produced nearby but rather from sources miles away. While there are thousands of plants that cause allergic reactions, the most common pollen allergy triggers are grasses, trees, and weeds. Here are some of the usual suspects for each:

Common Grass Pollen Allergy Triggers

  • Bermuda grass
  • Johnson grass
  • Kentucky bluegrass
  • Ryegrass
  • Sweet vernal grass
  • Timothy grass

Common Tree Pollen Allergy Triggers

  • Birch
  • Beech
  • Boxelder
  • Cottonwood
  • Cypress 
  • Elm
  • Hickory
  • Maple sycamore
  • Mountain juniper
  • Mulberry
  • Oak
  • Olive
  • Pecan
  • Walnut

Common Weed Pollen Allergy Triggers

  • Common pigweed
  • Common ragweed
  • English plantain
  • Goosefoot
  • Mugwort
  • Saltwort
  • Wall pellitory


There’s a common misconception that all flowers cause symptoms such as allergic rhinitis (hay fever). In reality, plants fertilized by insects, such as roses and some flowering trees, do not typically cause allergic rhinitis.3

How to Deal with Pollen Allergies

Many people cope with pollen allergy symptoms, or spring allergies, with over-the-counter medications and countless packs of tissues. Symptoms can include: 

  • Sneezing
  • Runny nose
  • Scratchy throat
  • Irritated eyes
  • Coughing

Here are seven tips to help you deal with pollen—and save on tissues:4

  • Shower after working outside. Wash your hair, eyes, and eyelashes.
  • Remove work clothes outdoors after working outside and carry them in a bag to the washing machine.
  • Take allergy medicines 30 minutes before going outdoors.
  • Stay indoors when pollen counts are high for pollens you’re allergic to.
  • Delegate yard work to someone else, or wear a microfiber facemask.
  • Keep windows closed at home and when driving, and when possible, use an air conditioner.
  • Use high-efficiency particulate air (HEPA) filters for furnaces and vacuum cleaners. 

Knowing that your symptoms can change from day to day depending on the weather—and that they could be caused by pollen floating in the air from miles away—doesn’t make finding relief any easier. But learning more about potential causes, allergy testing options, and trigger avoidance methods is a good start. To learn more about your pollen allergy symptoms, check out our in-depth analysis of symptoms.

Tools for Understanding Allergies


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  1. https://www.pollen.com/allergy/pollen-allergens.
  2. https://www.aaaai.org/conditions-and-treatments/conditions-dictionary/pollen.
  3. https://www.aafa.org/pollen-allergy.
  4. Discover the connection: Reduce Exposure to Your Allergic Triggers. Thermo Fisher Scientific Inc. 2018.