birkepollen

Birkepollen is the pollen produced by birch trees, particularly species in the genus Betula. It is a common component of springtime air in temperate regions and is a well-known aeroallergen in human health.

Biology and appearance: Birch pollen grains are small, roughly 20–25 micrometres in diameter, and are monosulcate, containing a single elongated pore. They are produced in catkins and released by the wind in large quantities, often forming visible dust during peak season.

Season and distribution: Birch pollen is widespread in Europe, Asia, and North America where birch stands exist. The pollen season typically runs from late winter to spring, with the highest concentrations in mid- to late spring. Timing varies by latitude, altitude, and weather conditions.

Health impact and allergenicity: Birch pollen is a major allergen in temperate climates. In sensitive individuals it can provoke allergic rhinitis, conjunctivitis, and sometimes asthma. Bet v 1 is the principal allergen; cross-reactivity with related proteins in various fruits and vegetables can cause oral allergy syndrome in some people.

Monitoring and research: Pollen counts are collected by aerobiological networks using volumetric samplers; results are reported as grains per cubic meter and inform daily or weekly pollen forecasts for allergy management.

Ecology and environment: As a wind-dispersed pollen, birch pollen contributes to reproductive success and gene flow in Betula; long-distance transport can expose distant populations to nonlocal pollen.

See also: Birch, Betula, Pollen, Allergies.