Phénoclim is the main citizen science program of CREA Mont-Blanc (Research Center for alpine ecosystems). The aim of this program is to evaluate the influence of climate change on the phenology of plant and animal species (e.g. blooming period for plants, egg-laying for birds...). Since its creation in 2004, 40 000 observations of plants were done by volunteers in mountain areas of 4 european countries (France, Spain, Italy, Switzerland). The program focuses on 10 plant species (hazel, spruce, birch (2 species), lilac, larch, coltsfoot, primrose, mountain ash, ash). Volunteers observe each week the plant individuals they selected and note the appearance of phenological events (e.g. burburst, blooming).