Prolonging the period of allergenic burden: late-flowering grasses and local peculiarities

Abstract

Background: The grass pollen season is characterized by a particularly long duration, covering the months May to July in Europe but can vary depending on the altitude and geographical location. Methods: Three grass species whose flowering period takes place late in the season are discussed in detail: Phragmites australis (common reed), Miscanthus spp. (silvergrass), and Zea mays (maize). Results: Phragmites australis flowers between August and September and provides significant pollen concentrations at sites with large reed populations. Miscanthus spp. flowers from August to October and is found as an ornamental plant in urban areas and as a crop plant in rural areas. Zea mays flowers from July to October and can cause discomfort especially in the vicinity of cornfields. Discussion: Phenological observations are an important part of aerobiological routine work to gain insights into regional peculiarities like late-flowering grasses, which play a role in prolonging the duration of the grass pollen season.