Pollen Count & Forecast for Baltimore

Baltimore’s spring allergy season (March-May) is dominated by Oak and Maple pollen; Oak (Quercus) is high in Druid Hill Park and Patterson Park; Maple (Acer) is common along residential streets. Birch (Betula) is in Gwynns Falls Leakin Park. Summer (May-July) sees high Grass (Poaceae) pollen levels, originating from Federal Hill Park and Patapsco River banks. Late summer has Ragweed (Ambrosia) in urban vacant lots.

Coastal humidity from the Chesapeake Bay and the urban heat island effect trap pollen in street corridors. Autumn and winter have elevated Mould (Alternaria, Cladosporium) spore counts; these are from decomposing leaf litter in Herring Run Park and damp masonry in old city districts.