Predicting Pinus sylvestris and Pinus nigra Arn. Ssp. Nigra survival after wildfire in Southern French Alps

International audience; Pinus sylvestris and P. nigra are two wide spread species in the Mediterranean mountains of South Eastern France. P. Sylvestris stands represent the highest volume of standing wood in region Provence Alpes Côte d’Azur covering 280 000 ha of pure and mixed stands. P. nigra has been widely used in reforestation programs during the nineteenth century for soil protection covering more than 60 000 ha of pure stands in Southern French Alps. In this context, wildfires affecting steep hillslope areas may have severe consequences in terms of postfire erosion including debris flows and debris torrents. P. sylvestris is the most affected species by forest dieback since 2003 high temperature wave and drought. Pinus nigra and P. sylvestris postfire mortality was monitored after a winter fire in a mid-high elevation (1500 m) mixed P. nigra – P. sylvestris stand in the French Southern Alps. Tree dimensions varied in a range of 13.0-42.0 cm for DBH and 7.7-19.6 m for height and in a range of 13.2-40.1 cm for DBH and 8.0-19-0 m for height for Pinus nigra and P. sylvestris respectively. Three years after fire, survival was total when the extent of scorch was less than 2/3 for both species and survival was 70% and 91% when crown scorch was >2/3 for Pinus nigra and P. sylvestris respectively. Detailed analysis showed a similar fire resistance of both species after this specific fire event