Depending on where you live, there are generally three pollen seasons. The start and end dates of these seasons, as well as the specific plants involved, vary by climate.
Trees generally pollinate in the spring. Birch, cedar, cottonwood and pine are big allergy triggers. Grass releases its pollen in the summer. Timothy, Johnson and rye grasses are all examples of allergens in this category. Weeds cause hay fever in the fall. Ragweed is the biggest offender as it can grow in nearly every environment.
Avoiding your allergy triggers is the best way to reduce symptoms. Limit outdoor activities during days with high pollen counts. Keep windows closed (at home and in the car) to keep pollens out. Take a shower after coming indoors. Pollen in your hair can get on your pillow and cause allergy problems at night.
Allergies can’t be diagnosed by medical history alone. An allergist/immunologist can diagnose your allergies, and then determine the specific triggers that cause them, through simple tests.
If you have allergies, you may want to keep track of pollen counts in your area through the National Allergy Bureau’s website at www.aaaai.org/global/nab-pollen-counts.aspx.
— Source: American Academy of Allergy, Asthma & Immunology