Tree Pollen Allergy

What Is a Tree Pollen Allergy?

Tree pollen is the cause of most spring pollen allergy symptoms. Tree pollen allergy causes seasonal allergic rhinitis, also called “hay fever.” Pollen from weeds and grasses also trigger allergic rhinitis.

Tree pollen season also often overlaps with grass pollen in the late spring and summer. Throughout the U.S., trees produce the most pollen from March through April. But in some regions, such as the South, trees may produce pollen as early as December or January and peak at multiple times during the year.¹

Some trees produce pollen you can see (a fine, yellow dust that covers outdoor surfaces). Other trees produce pollen that can’t be seen.

All tree pollen carried by the wind is light and easy for the wind to carry. This wind-carried pollen is the only type of tree pollen to which most people are sensitive. Because of this, it can easily find its way into your eyes, nose, and lungs. When that happens, tree pollen triggers the symptoms of allergic rhinitis.

How Do I Know If I Have a Tree Pollen Allergy?

Seasonal allergic rhinitis is very common. Around 81 million people in the U.S. have seasonal allergic rhinitis.^2,3 Talk with your doctor about your symptoms. If they think you have allergic rhinitis, they will likely recommend allergy treatment. If your symptoms do not improve, ask for a referral to a board-certified allergist.

An allergist can diagnose a tree pollen allergy. They will ask about your personal and medical history, do a physical exam, and run tests to find out the types of trees you are allergic to. Allergists know how to interpret the test results to give you an accurate diagnosis.

What Are the Symptoms of a Tree Pollen Allergy?

If you have a tree pollen allergy, you will only have symptoms when the pollen that you are allergic to is in the air. Symptoms of allergic rhinitis include:

• Runny nose (also known as rhinorrhea – usually a clear, thin nasal discharge)
• Stuffy nose (due to blockage or nasal congestion)
• Postnasal drip (mucus runs from the back of your nose down your throat)
• Sneezing 
• Itchy nose, eyes, ears, and mouth
• Red and watery eyes
• Swelling around the eyes
• Shortness of breath, coughing, and/or wheezing

If you have asthma and are allergic to tree pollen, you may have allergic asthma. This means tree pollen triggers your asthma symptoms.

A tree pollen allergy can also cause you to have itching or swelling in or around your mouth when you eat certain foods. This is called pollen-food allergy syndrome (PFAS), also called oral allergy syndrome (OAS). (It can happen to people allergic to some grasses or weeds as well.)

What Is Pollen-Food Allergy Syndrome?

If you are allergic to certain trees, such as birch or alder tree pollen, you may react to certain foods.

PFAS happens because some tree pollen is similar to the protein in some fruits, vegetables, and nuts.⁴ Your immune system gets confused and can’t tell the difference between them. Eating these foods may cause your mouth, lips, tongue, and throat to itch or swell.

You may be able to eat foods that cause PFAS symptoms if you remove their skins and/or cook them. Heat affects the proteins (breaks them down), so you may be able to eat these foods cooked instead of raw. For example, a fresh tomato may cause symptoms, but a person with PFAS may be able to eat cooked marinara sauce or ketchup without symptoms.

Birch tree pollen can cross-react with:

Alder tree pollen can cross-react with:

• Almond
• Apple
• Celery
• Cherry
• Hazelnut
• Peach
• Pear
• Parsley

Talk with an allergist if you think you have PFAS. Ask them:

• If you need allergy testing or any other tests to help diagnose it
• If you should avoid eating foods that cause symptoms
• To give you a written allergy treatment plan and to guide you on what medicines to use
• When to follow up with your doctor

What Types of Trees Cause the Most Allergy Symptoms?

Some of the trees that cause the most allergy symptoms throughout the United States are:⁵

• Alder
  • Found in every state except Nebraska and South Dakota
  • A common cause of PFAS
• Ash
  • Mostly found in Eastern and Southeastern states, but can be found in most states except Alaska and Hawaii
  • Very allergenic
• Aspen
  • Found in every state except Hawaii
  • Related to cottonwood and poplar
• Beech
  • Found in the Northeast, Eastern Midwest, and the South
• Birch
  • Found in every state except Hawaii
  • A common cause of PFAS
• Box elder
  • Found in every state except Alaska and Hawaii
  • A type of maple that is very allergenic
• Cedar
  • Found in coastal states in both the Eastern and Western United States and Oklahoma
  • Related to juniper
• Cottonwood
  • Found in every state except Hawaii
  • Related to aspen and poplar
• Elm
  • Found in every state except Alaska, Colorado, Hawaii, Montana, and Wyoming
• Hickory
  • Found in the Midwest, Northeast, and Southeast
  • Very allergenic
• Juniper
  • Found in every state except Alaska and Hawaii
  • Related to cedar
• Maple
  • Found in every state except Alaska and Hawaii
• Mulberry
  • Found in every state except Alaska and Nevada
  • Very allergenic
• Oak
  • Found in every state except Alaska and Hawaii
  • Very allergenic
• Olive
  • Found in every state except Alaska and Hawaii
• Pecan
  • Found in the Midwest, Northeast, and Southeast, as well as California and Arizona
  • Very allergenic
• Poplar
  • Found in every state except Hawaii
  • Related to aspen and cottonwood
• Walnut
  • Found in every state except Alaska, Arizona, Colorado, Hawaii, Idaho, Washington, Nevada, Oregon, and Utah
  • Very allergenic
• Willow
  • Found in every state except Alaska and Hawaii
  • Very allergenic

Are Tree Pollen Counts Getting Worse?

Trees are effective tools at helping regulate climate. Many trees are monoecious, which means they have pollinating flowers and fruit-, seed-, and nut-bearing flowers on the same plant. But there are some fruit-, seed-, and nut-bearing trees that do not release pollen. These are called “female” trees. These trees rely on small animals and insects to transfer pollen. Other trees release pollen but do not produce fruit, seeds, or nuts. These are called “male” trees. They rely on the wind to carry pollen to other trees for pollination.

More wind-pollinating trees can lead to increased pollen production. Since 1990, pollen seasons have 21% more pollen. Tree pollen levels saw bigger increases than grass or weed pollen.⁶ “Botanical sexism” (the preference to plant “male” trees) may be partly to blame for the increase in tree pollen. Historically, many urban planners have chosen wind-pollinating (“male”) trees instead of fruiting (“female”) trees when designing communities, streets, and parks. This practice leads to more pollen in cities. Experts believe this is part of the reason why pollen counts have been increasing.⁷

Diversifying the types of trees in parks and urban areas may help reduce the amount of pollen in the air. Planting more female trees may help regulate surface temperature while also reducing the amount of pollen in nearby areas.

What Is the Treatment for Tree Pollen Allergy?

It’s helpful to know what types of trees you are allergic to. You can reduce your exposure to the trees you are allergic to by watching pollen reports for your area. You can also learn what time of year tree pollen starts to appear in your area so you can start allergy treatment before it begins for better relief during the season.

Here are some steps to managing your tree pollen allergy:

1. Track the tree pollen count for your area. The news media often reports the count for your area, especially when pollen is high. You also can get your area’s pollen counts from the American Academy of Allergy, Asthma & Immunology’s (AAAAI) National Allergy Bureau.

2. Stay indoors in central air conditioning when the pollen count is high, if possible. Keep your windows in your house and car closed too, if possible. Get a Certified Asthma & Allergy Friendly® air filter and/or HEPA filter for your air conditioner.

3. Prevent pollen from coming into your home. If you spend a lot of time outside during peak pollen time:

• Take your shoes off outside
• Don’t wear your “outside” clothes to bed
• Cover your hair when outside or wash it at night
• Wipe off pets before they enter your home
• Shower after coming inside your home after being outdoors for a long time
• Keep windows closed, if possible, during pollen season or peak pollen times.
• Dry your clothes in a clothes dryer or on an indoor rack, not on an outdoor line.

4. Take allergy medicines and start treatment before tree pollen season starts in your area. Find out what time of year tree pollen starts to appear in your area so you can start allergy treatment at least 2 weeks before pollen season begins. Many over-the-counter medicines work well to control pollen allergy symptoms. They can also help eye, nose, and airway symptoms.

5. Talk with an allergist about immunotherapy. There are two types: allergy shots and sublingual immunotherapy (SLIT). This type of treatment may help give you long-term relief. If you have allergic asthma, your Asthma Action Plan may include some of these allergy treatments to help you keep your asthma under control.

Should I Move to Get Relief from My Tree Pollen Allergy?

Trees that produce allergenic pollen grow in every state. Tree pollen also spreads easily through the air, so you may be exposed to pollen of trees not on your property. If you move, you may get some relief for a short time. But you can develop allergies to the trees in your new location in a few years. Instead, work with an allergist on a solid allergy treatment plan.