Ambrosia is an invasive exotic plant.
Its pollen, emitted at the end of summer, causes strong allergic reactions (rhinitis, etc.) in sensitive people. It is also a threat to agriculture and to biodiversity.
Thus, to avoid an invasion by ragweeds as known in certain areas where the fight becomes very expensive, it is strongly recommended to implement, as early as possible, prevention and control measures against these species.
If you think you have found ambrosia:
1 - Have the observation confirmed by the municipal "ambrosia" referent Emmanuelle MIHÉ NGUYEN (send photos of the plant by email, specify the covered area, the address, if in the public or private domain - E-mail:
2 - If it is indeed ragweed, report it on the platform http://www.signalement-ambroisie.fr/
3 - Depending on the state of development (flowering, pollination, fruiting, etc.) and the amount of ragweed observed, the referent will tell you the procedure to follow for its destruction
For more information: the Ambrosia Observatory https://ambroisie-risque.info/