Asthma-Allergy Denmark has detected pollen from alder trees and hazel bushes in its monitoring stations, officially kicking off the 2025 pollen season. This marks the beginning of allergy symptoms like sneezing, itchy eyes, and congestion for around one million Danes.
Recent measurements show a slight increase in pollen levels from these trees, following the usual seasonal pattern. Mathilde Kloster, head of pollen monitoring at Asthma-Allergy Denmark, notes that while the season is starting in early February as expected, an even earlier onset was avoided this year.
How intense the season will be depends on several factors, such as last year’s rainfall and nutrients during pollen formation, as well as the weather leading up to and during flowering. Cooler temperatures in early February could slow down pollen release, while warmer weather might speed it up. Rain, on the other hand, can help wash pollen out of the air.
Many people allergic to birch pollen may already be feeling symptoms due to cross-reactions with alder and hazel pollen, which is common. Experts recommend checking daily pollen forecasts and consulting a doctor to ensure proper treatment throughout the season.
