The earthworks required to operate the ski area have an impact on the soil and existing vegetation. Even if our first approach is to reduce their footprint to the bare minimum, it is necessary to develop revegetation techniques to encourage rapid regrowth. We are looking for both rapid recovery (a mixture of seeds called "Trois Vallées" with a choice of fast-growing species such as Timothy and Ryegrass) and diversity (a mixture of seeds called "Végétal Local" to ensure better biodiversity).
The objectives are numerous:
- Reduce the risk of erosion induced by exposed soils, particularly in areas with steep slopes.
- Sustaining agricultural potential by quickly regaining good fodder potential to ensure the agricultural activity of our mountain pastures while being compatible with the specifications of the AOP Beaufort.
- Restoring biodiversity by gradually finding a procession of plant species close to the original one and finding diverse and attractive habitats for wildlife.
- Save our landscapes mountain emblematic.
Example of vegetation monitoring below on the intermediate part of the Eclipse trail, observable thanks to our Landscape Observatory since 2021.
Focus
Technical revegetation day
In 2023, the Société des 3 Vallées organized a technical day on the theme of revegetation of mountain slopes with local seeds. Around twenty managers of slope services from all over France as well as experts on the subject met around round tables on the importance of soils and local seeds.
Actions tested in Courchevel:
- The “Green Hay” is a re-vegetation technique carried out on Courchevel-Moriond in 2017 with INRAE Grenoble (ex-IRSTEA) and CBNA (National Alpine Botanical Conservatory) as part of the “Sem'lesAlpes” project. This seeding technique consists of mowing and spreading hay that has just germinated and is located in the immediate vicinity of the reworked site.
- The “seed peddlers” is a re-vegetation technique carried out as part of the work on the Eclipse track in 2021 and 2022 in partnership with the CBNA. This technique consists of collecting seeds directly nearby with a manual machine that will brush and vacuum the top of the plants.
This project was also an opportunity to set up an integration project for young people in difficulty with the Sauvegarde2Savoie association. - “Local Plant” brand: All the earthworks for the Eclipse track (world championship track) were reseeded with a mixture composed of 20% so-called “Local Plant” seeds and 80% with seeds from the classic 3 Valleys mix. These “Local Plant” seeds come from the seeds of species selected in the mountains near Gap and then cultivated before they are delivered for seeding on site.
From now on, this 80/20 rule applies to all of our earthworks projects. - Etrepage : In 2023, the Chenus and Pralong-Bellecôte slopes were subject to the revegetation technique by topping. This technique consists of recovering (before terracing the slope) the upper layer of the soil to promote rapid regrowth by maintaining the root body of local plants and their vegetative part.
Water & agriculture
