On this scale, it hasn’t been done for decades. In the Val-d’Oise, on the Pierrelaye-Bessancourt plain, a forest is being entirely planted: a million trees, in total, over more than 1,300 hectares, will emerge from the ground. It is an additional lung for the Île-de-France and a means of giving a horizon to lands which have been deeply polluted.
What we see for the moment of this forest are tiny trunks a few tens of centimeters high, planted in alignment in a field, a few hundred meters from one of the many highways that cross this sector of ‘Ile-de-France.
This land can be considered barren. It has been contaminated for decades by the landfill sludge from the region. This forest is therefore a means of giving it a future, explains Bernard Tailly, the president of Smapp, the union which manages the project. “There were only two outcomes: to keep the natural space by occupying it in a sustainable way, which resists urbanization, or so urbanization, he indicates. Unfortunately, in recent years the area has become almost abandoned. It is therefore a reconquest of space for the long term. “
The first trees were planted three years ago. The union has already bought half of the land. It will take almost half a century for this forest to mature. She is composed notably maple trees, cedars, lime trees and oaks, with the concern of adapting to the effects of climate change, says Michel Beal, director for the ONF of the Île-de-France Ouest agency.
“The forest must be there tomorrow, the day after tomorrow, in twenty years, in fifty years, in a hundred years and ensure that the species that we plant today are still resistant, adapted to the climate of the 30 or Next 40 years “, he explains. “We are working with data from the IPCC on climate change, continues Michel Beal. Today, we have a veritable cocktail of essences: more than thirty species have been planted, so as not to put all the eggs in one basket. “
Due to soil pollution, fruit trees were excluded. Picking mushrooms will also probably be prohibited. The forest will extend over seven municipalities. It will make it possible to build a bridge between the valleys of the Oise to the north and the Seine further to the south. The first animals expected are birds. The cost of this forest is estimated at 85 million euros, mainly for the purchase of land and rehabilitation.