[Science News] – Meise Botanic Garden takes part in the reintroduction of mountain arnica in the French Ardennes
On the 6th of November, a team from Meise Botanic Garden went to the French Ardennes, in the Rocroi region, to help plant several hundreds of mountain arnica (Arnica montana) specimens. This operation has marked the culmination of an ambitious reintroduction project led by the Conservatoire botanique national (CBN) du Bassin parisien (National Museum of Natural History, Paris – MNHN) and the Parc naturel régional des Ardennes (PNR), in partnership with Meise Botanic Garden.
An emblematic plant in peril
Arnica, renowned for its medicinal properties, is a flagship species of nutrient-poor acidic grasslands. In Champagne-Ardenne, the subspecies montana nowadays only remains in the northern Ardennes, where it is considered critically endangered. Formerly present in about fifteen municipalities, it currently persists in only two sites, barely totalling a dozen individuals. The gradual loss of its natural habitats is due to agricultural intensification and afforestation.
The key role of Meise Botanic Garden
This reintroduction effort has been built on years of scientific research carried out by Fabienne Van Rossum, a researcher in population and conservation genetics , along with the technical expertise of Sarah Le Pajolec in plant cultivation at Meise Botanic Garden. The project also benefits from experience gained through a similar initiative conducted about ten years ago as part of the LIFE Herbages Programme, which aimed to strengthen arnica populations in southern Belgium.
The seeds used for the reintroduction in France were collected from these now-thriving Walloon populations, whose genetic composition showed a close affinity with those of the French Ardennes. Sowing and plant propagation were carried out from these seeds at the Botanic Garden and at the MNHN. Germination and growth conditions were controlled to ensure high-quality plant material.
A long-term conservation programme
Two sites were selected by experts from the CBN and the PNR. Before planting, the soil was stripped to restore suitable conditions for arnica establishment, and protective fencing was installed afterwards to prevent browsing by wildlife. These sites will be monitored over a ten-year period to ensure appropriate management and to assess the long-term viability and extension of the new populations.
In total, nearly 2,000 young arnica plants cultivated by Meise Botanic Garden and by the MNHN were planted across the two sites, under the supervision of the CBN and PNR. This operation is a fine example of cross-border cooperation, combining scientific rigour with on-the-ground commitment. See you in a few years to admire the carpets of arnica that will once again bring life to these emblematic Ardennes landscapes.