The metallicolous grasslands of Mortagne du Nord

Every year in Mortagne-du-Nord, a commune within the Regional National Park, the so-called metallicolous or calaminarian grasslands come into bloom. The presence of heavy metals in the soil produces flora unique to Nord-Pas de Calais which is of considerable scientific interest.

The calaminarian grasslands are located on the disused plot of a former industrial site.

Mortagne du Nord was once (from 1901) home to a zinc extraction plant (by the edge of Scarpe canal). Zinc was brought here, as well as lead and calamine. A production unit was also set up in the neighbourring commune of Thun Saint Amand. The two sites employed up to 1500 French and Belgian workers.

Until 1963, the year of its closure, the site accumulated slag, which was dispersed by the wind and polluted the surrounding land.

Today the site belongs to the commune and is part of the Natura 2000 network. The thick grass which grows here now keeps most of the pollutants in the soil, preventing wind dispersal or leaching.