Pollen Count & Forecast for Des Moines

Des Moines’ spring allergy season (March-May) is dominated by Maple and Ash pollen; Maple (Acer) prolific in Water Works Park; Ash (Fraxinus) widespread along Des Moines River. Oak (Quercus) contributes significantly from Gray’s Lake Park. Summer (May-July) sees high Timothy Grass (Phleum pratense) pollen levels, originating from Raccoon River banks. Late summer brings Common Ragweed (Ambrosia artemisiifolia) from open prairies.

The Des Moines River valley traps airborne particles; agricultural lands contribute to high pollen concentrations. Autumn and winter see elevated Mould (Alternaria, Cladosporium) spore counts, from decaying crops and damp leaf litter in Walnut Woods State Forest.