Allergy alert: Action day to fight ragweed | Umweltbundesamt

Maria Krautzberger, President of UBA, said: "Climate change can also accelerate the spread of highly allergenic ragweed, as we have seen throughout Europe and in Germany. Gardeners must take action by notifying the authorities or removing the ragweed themselves." Property owners in Switzerland and Hungary are even legally required to prevent the plants from blossoming by pulling it out in good time. A similar obligation in Germany needs to be discussed at federal level.

The pollen of this plant native to North America can trigger severe health problems in the smallest of concentrations, including hay fever, conjunctivitis, and allergic asthma. The plant's late blooming time (July to October) extends the pollen season in general – for many allergy sufferers, too. Ragweed has been widespread for a long time in warmer countries such as Hungary, Italy or France. As a consequence of climate change, experts predict that the plant will continue to spread in Germany.

Besides its allergenic effect ragweed can be problematic for some agricultural crops (e.g. sunflowers), as is already the case in Hungary. In Germany the plant has spread in household gardens, on uncultivated land, fields, and cutting gardens. Building sites, roadsides and field edges have also been affected. Ragweed seeds were originally introduced for example in  contaminated bird feed or in construction lorries. Ragweed can be effectively controlled if the plant is pulled out well before it blossoms. Some local authorities have started a systematic fight against the plant. Berlin, for example, has commissioned ragweed scouts to track down and pull out the plant.

Ragweed can only be fought effectively by taking action across biotopes (roadsides, uncultivated land, building sites and other public spaces). In addition to the public authorities at federal and state level who are responsible for public space, private property owners could also be required to remove ragweed on their land. It would be prudent to introduce a nationwide standard regulation such as a reporting requirement or a basic duty to combat the plant, also in consideration of cross-border pollen flight.