La Croix-Verte is an area under renaturation located on the Rennes 1 campus, between the university library and the new metro line. Its renaturation is a commitment of Rennes Metropole in connection with the creation of the metro line B, in order to compensate for the destruction of other green spaces in the city. It is composed of 3 water points fed by an underground river and its objective is to promote biodiversity. It is in this context that the Mycelium project was born. Its purpose is to monitor withe meteorological sensors the evolution of this area in transition, so by definition, unstable. These sensors are placed in a little box we call SoLo node.