As we approach the handover of our project to restructure an urban complex on rue des Poissonniers in Paris (18th arrondissement), the agency is conducting an ecological experiment in line with our research and previous initiatives. The project involves seeding a 300 m² green roof using the limestone meadow from another of the agency's well-known projects: the School of Science and Biodiversity in Boulogne-Billancourt.
As with the enrichment of the school's meadow in 2023 from the meadows of the Domaine National de Marly-le-Roi, this new operation involves transferring the hay flower from the annual mowing of the school's meadow (carried out that very morning) by depositing it a few kilometres away, on the roof of the student residence in Paris.
The first stage is to prepare the ground to receive the hay. The receiving soil is turned over and raked by hand. The soil is made up of topsoil and limestone outcrops, creating different environments: dry meadow, thicket, limestone hem.
Using the "direct grassing" or "green transfer" technique, the hay is spread evenly over the whole of the receiving meadow, without excessive clumps or gaps.
The final step is to put up a net to prevent the hay from flying away and to protect the seeds from predation by pigeons.