Agricultural policies have recently integrated climate issues and deploy a range of measures aimed at changing farming practices. Looking beyond the institutional discourse which emphasizes the difficulties of involving farmers in measures for dealing with climate change, the results of our research provide a basis for envisaging other lines of reflection. The adoption of new practices by farmers is only partially a response to the normative measures of government policy, but it depends above all on the way these actors integrate climate issues in their value systems. Based on a qualitative methodology involving semi-structured interviews, the results of the research presented here highlight the modes of decision-making of farmers, that they are based on their own professional and social networks. Whatever the changes put into practice, we show that they are based on a common core of perception, what is referred to by French rural sociologists as the peasant ideology with an attachment to the land and the need to protect it as a central value. Nevertheless, we shall nuance this result by distinguishing two forms of justification for the introduction of new practices: the reference to an ecological modernization versus an approach related to a global ecological approach. If the major part of farmers doesn't refer to a global view of earth, which represents the mainstream discourse about climate change, they take care of land on behalf of a heritage duty.