Ragweed triggers severe allergy symptoms despite dry weather

Ragweed is causing significant problems for allergy sufferers in Upper Austria despite the dry conditions, ORF’s Upper Austria service reports. The highly allergenic plant is less widespread there than in Austria’s eastern and southern states, but even relatively small amounts of pollen can trigger symptoms.

Mugwort pollen levels are gradually declining, while the share of ragweed pollen is rising. Also known as common ragweed, the plant grows mainly in weed-covered areas, along roadsides and embankments, and on undeveloped land.

In Upper Austria, ragweed is found mainly in the Danube region and the central part of the state. It is significantly more common in eastern Austria and the southern states.

Hot and dry conditions are generally not ideal for ragweed growth, but they do little to reduce the burden on allergy sufferers. “Ragweed is so allergenic that very few pollen grains are needed to cause symptoms,” said Markus Berger of the Pollen Warning Service.

Researchers have not yet fully established why some plants’ pollen is more allergenic than others. “We only know that ragweed allergens cause strong symptoms very quickly in people,” Berger said.

Ragweed is an invasive plant from North America. People who find it nearby can report its location through the Ragweed Finder platform, which also shows where the plant has already been recorded.

Other plants can also cause symptoms at this time of year. Goosefoot family plants, for example, grow on ruderal sites, meaning areas heavily altered by human activity where weeds and other pioneer plants become established. Their share of pollen has increased significantly this year compared with previous years because of the hot and dry days.