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I dreaded ragweed season—late summer and early fall—when I would get hay fever. I never knew when I would start sneezing and coughing and feeling bad. So I stayed inside a lot and skipped my fall garden plantings. Then I found out how to check for pollen counts in my area. Now I can plan my outdoor activities for when the pollen counts are low. – Maria, age 39

What are pollen and mold?

Pollen. Pollen is very fine powder that comes from trees, grasses, flowers and weeds. Wind and birds carry this pollen from plant to plant to fertilize them. When people who have a pollen allergy inhale the pollen, they get allergy symptoms. People can be allergic to different types of pollen. For instance, some are allergic to pollen from only beech trees; others are allergic to pollen from only certain kinds of grasses.

Did you know… Plants with brightly colored flowers and sweet smells rarely cause allergy symptoms? That’s because insects and birds rather than wind usually carry the pollen from these plants.

Mold. Mold is a fungus, which makes spores. These spores float in the air like pollen. When people who have a mold allergy inhale the spores, they get allergy symptoms. Molds live indoors (especially in moist places like bathrooms, kitchens, and basements) and outdoors (on rotting logs and fallen leaves).

What do pollen and mold counts mean?

Pollen counts. Pollen counts give the number of grains of pollen in a certain amount of air in a set time period (usually 24 hours). The pollen is measured for specific plants such as grasses, oak trees and cottonwood trees. Pollen counts change with the weather (rain, humidity, sun and wind) and time of day; for example, they are usually higher on warm, breezy days and lower on chilly, wet days.

Some places give a total pollen count rather than pollen counts of specific plants. A high total pollen count doesn’t mean you will have allergy symptoms. The pollen from the plant you are allergic to may not be high.

Mold counts. Mold counts give the number of mold spores in a certain amount of air in a set time period (usually 24 hours). As the weather changes, mold counts change. For example, some kinds of mold spores increase with dry, breezy weather. Others increase with high humidity, fog and dew.

How do pollen and mold affect allergies and asthma?

Pollen and mold spores in the air enter the nose and throat. They can cause allergy and asthma symptoms in people who are allergic to them.

An allergy occurs when you react to things like pollen and mold that don’t affect most people. If you come into contact with something you are allergic to (called an allergen), you may have symptoms. This is called an allergic reaction.

Asthma is a lung disease that makes it hard to breathe at times. When people with asthma come into contact with something they are allergic or sensitive to, their airways become narrower. That makes it harder for air to get to their lungs. Symptoms include coughing, wheezing (a whistling sound when a person breathes) and a feeling of tightness in the chest.

What are the symptoms of pollen and mold allergies?

The symptoms of mold and pollen allergies include sneezing; runny or stuffy nose; itchy throat or inside of ears; hives; swollen eyelids and itchy eyes; and coughing, wheezing and trouble breathing.

What plants that have pollen are most likely to cause allergy symptoms?

When a plant begins to flower, its pollen goes into the air.

Weeds. They usually let go of their pollen in the late summer and fall. Ragweed is the weed most likely to cause hay fever. Other weeds that let go of pollen and can cause pollen allergy symptoms include:

  • burning bush (also called kochia, Mexican fireweed, summer cypress)
  • cocklebur
  • lamb’s quarter
  • pigweed
  • plantain
  • red (sheep) sorrel
  • Russian thistle
  • sagebrush
  • mugwort
  • scales (atriplex)
  • tumbleweeds

Trees. Most trees let go of their pollen in the late winter and early spring. The trees most likely to cause allergy symptoms include:

  • ash
  • aspen
  • beech
  • birch
  • box elder and other maples
  • cedar
  • cottonwood
  • elm
  • mulberry
  • oak
  • willow

Grasses. There are hundreds of types of grass. Grasses let go of their pollen in the late spring and early summer. Those most likely to cause allergy symptoms include:

  • Bermuda
  • Johnson
  • Kentucky bluegrass
  • orchard
  • redtop
  • rye
  • sweet vernal
  • timothy

How can I find pollen and mold counts?

  • Check the weather section of your local newspaper.
  • Go to a weather information website and enter your zip code.

When should I check pollen and mold counts?

If you have pollen or mold allergies, you should check these counts often, especially when you’re planning outdoor activities. You also can use the counts to decide if you need to adjust the dose and kind of allergy or asthma medicine you take. Talk to your allergist about how to do this.

How can I avoid or limit my contact with pollen and mold?

  • Limit your time outdoors when pollen and mold counts are high.
  • Wear a dust mask that people like carpenters use (found in hardware stores) when you need to do things like cut the grass or rake leaves. Don’t wear your outdoor work clothes in the house; they may have pollen on them.
  • Clean and replace air conditioner filters often.
  • Use a clothes dryer rather than dry clothes outside, where they can collect pollen.
  • If you take a vacation, choose places and times of the year when pollen and mold counts won’t be high.

Keep in mind… If you have allergies to plants and molds where you live, you may get allergies to different plants and molds within a few years after moving to a new area. Talk to your allergist about your move. You also may want to try living in the new area for a few months before moving there.

Who should treat pollen and mold allergies?

Allergists are experts in treating allergies and can treat your allergy or asthma symptoms.

Does health insurance cover treatment for pollen and mold allergies?

Most health insurance plans cover allergy treatment.

Ask your insurance carrier:

  • Do I need a referral from my doctor to see an allergist?
  • Does my insurance cover patient education or special services for my allergies or asthma?
  • Does my insurance cover a pre-existing health problem? This usually means any health problem that you had before you joined your current health plan.
  • What medicines does my plan cover?

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