Republished: Feb 22, 2022

Reviewed by: 
Rebecca Rosenberger

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.

What are pollen allergies?

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

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

Typical symptoms and management tips

Pollen allergy symptoms can include:

  • Sneezing
  • Runny nose
  • Scratchy throat
  • Irritated eyesCoughing

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

  • Shower after working outside. Wash hair, eyes, and eyelashes.
  • Remove work clothes outdoors, place them in a bag, and carry them to the washing machine.
  • Consider taking your allergy medicines before going outdoors if directed by your healthcare provider.
  • Stay indoors when pollen counts are high for pollens you’re allergic to.
  • Have someone else do your yard work, or wear a microfiber facemask.
  • At home and when driving, keep windows closed, and when possible, use an air conditioner.
  • Use high-efficiency particulate air (HEPA) filters for furnace 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


Track allergy symptoms and prepare for a visit with a healthcare provider.

Learn about specific allergens, including common symptoms, management, and relief. 

Are you a healthcare provider? Get comprehensive information on hundreds of whole allergens and allergen components.

  4. Discover the connection: Reduce Exposure to Your Allergic Triggers. Thermo Fisher Scientific Inc. 2018.