With summer just around the corner, there is one unwelcome accompaniment, grass pollen season.

After tree pollens kicked off the allergy season, from now until around August, grass pollens also join the party of potent allergens in the air.

The two overlap slightly until June, with pine and birch two particularly long-lasting tree pollens, before weed pollens also join the mix towards autumn.

A study carried out by the University of Utah shows the US pollen season is now starting 20 days earlier than ever, lasting over a week longer, and features 21% more pollen than recorded three decades ago.

Meanwhile, researchers at the University of Worcester say that pollen particles, and grass pollen specifically, are becoming more potent due to higher levels of carbon dioxide which is absorbed by plants.

As levels grow more potent, you may want to try:

If you suffer with hay fever, be sure to check pollen levels near you in the Weather & Radar app.