The rejection of pesticide use in non-agricultural areas is a subject of public policy, national initiatives, and collective activism. As private actors renew and expand their perceptions on the value of green space, the rise in sentiment against pesticide use is leading public policy makers to re-examine the management of these areas and orient it towards an approach that is more sensitive to the different requirements of non-agricultural terrains and the evolving functions of green space and Nature within cities. This study examines the problematic of pesticide use and it shows that the social and political interactions at the interface of these issues are changing the dynamics of green space and nature in cities. It is necessary to consider the questions posed by the public and the collective actions abandoning pesticide use. The approach from multiple scales allows the focus on actions at local level to observe how these last actors appropriate and treat these issues. I will use the study of a collection of documents to better understand the objective reasons for local mobilization and identify the fundamental reasons for their actions. The rejection of pesticide use has become an issue at the interface between public policy and public action. A wide variety of actors has taken on this issue and it is capable of local mobilization. Public policies have become increasingly dominant: a favourable context for local mobilisation, but limited by complex legal procedures. The collection of documents used in this article suggests that the rejection of pesticide use is becoming an integral part of the management of urban projects through multiple public policies and collective actions.