Birch (Tree)
Description
Birch trees (Betula species) are slender, medium-sized deciduous trees in the family Betulaceae. You can spot them by their distinctive white or silver bark that peels into thin, papery layers. Their leaves are triangular or diamond-shaped with serrated edges, and they release abundant wind-dispersed pollen during spring. Common species include silver birch (Betula pendula) and downy birch (Betula pubescens) in Europe, and paper birch (Betula papyrifera) in North America. Birch pollen is one of the most potent tree allergens and can travel long distances on the wind.
Allergy Symptoms
Birch pollen is a major allergen that commonly causes:
- Sneezing and runny or congested nose
- Itchy, watery, red eyes
- Coughing and throat irritation
- Asthma flare-ups and wheezing
Birch pollen allergies often trigger Oral Allergy Syndrome (OAS), where eating certain raw fruits, vegetables, and nuts causes itching or tingling in the mouth and throat. Common trigger foods include apples, pears, cherries, peaches, plums, kiwi, carrots, celery, hazelnuts, and almonds. Cooking these foods usually reduces or eliminates the reaction.
Typical Pollination Period
Birch trees typically pollinate from late March through May, with peak pollen release in April across most temperate regions of the Northern Hemisphere. In warmer southern climates, pollination starts earlier; in colder northern regions, it may extend later. Weather — especially temperature and rainfall — affects both timing and intensity.
Geographic Distribution
Birch trees grow throughout the temperate and boreal zones of the Northern Hemisphere:
- Europe: Especially common in Northern, Central, and Eastern Europe, where birch is one of the most significant allergenic trees
- North America: Found across Canada and the northern United States, particularly in the Northeast and Great Lakes regions
- Asia: Widespread throughout Siberia, Northern China, Korea, and Japan
Tips for Allergy Sufferers
- Check local pollen forecasts and stay indoors when counts are high
- Keep windows closed and use HEPA air purifiers indoors
- Shower and change clothes after being outside
- Antihistamines or nasal corticosteroids can help — talk to your doctor
- If you get Oral Allergy Syndrome, watch out for trigger foods during birch season
- For severe or persistent symptoms, consider allergy testing or immunotherapy