Pollen count
Air quality Airborne pollen Pollen concentration Pollen load
Airborne pollen is plant pollen carried through the air. For people with allergies, the species, concentration and individual sensitivity all matter.
What is travelling through the air?
Many trees, grasses and weeds release pollen for the wind to carry. Monitoring sites collect grains and identify their type and amount. Concentrations may use pollen grains per cubic metre of air, while other products use exposure categories.
A calendar without fixed appointments
Hazel and alder often appear early, followed by plants such as birch, grasses and mugwort. Temperature and plant development shift the start between years. A pollen calendar is therefore a guide. The birch tree has not read it.
How weather affects pollen
- Dry conditions help many plants release pollen.
- Wind disperses it and can bring it from other regions.
- Prolonged rain may wash pollen out; concentrations can rise again after plants dry.
The species belongs with the number
High grass-pollen levels matter differently to someone allergic only to birch than to someone with a grass allergy. Categories are also not defined identically across all providers and pollen types.
Beside a flowering meadow, conditions can differ from a regional model estimate. Forecast, actual surroundings and known individual triggers must be considered together. A low area-wide index does not guarantee freedom from symptoms.