Growing the Green Giant: Ecological Threats, Political Threats, and U.S. Membership in Sierra Club, 1892–Present

A growing body of research examines questions related to the emergence of environmental organizations and the growth of the environmental organizational field in the United States, but we need to know more about why particular environmental organizations grow or decline in terms of membership size over time. In this article, we draw on both qualitative and quantitative data to assess factors contributing to the growth of the Sierra Club, one of the United States’ oldest and largest environmental organizations. First, through an analytic narrative that synthesizes insights from secondary accounts of the history of the Sierra Club, we identify a variety of ecological and political threats that have led to growth in the Sierra Club from its founding in 1892 to the present day. Then, through time-series analyses of quantitative data, we show that two particular types of environmental and political threats—growth in carbon dioxide emissions and the presence of Republican Presidents—have led to growth in the Sierra Club from 1960 (when it began mass recruitment of members) to 2016. We contextualize these findings within the broader social scientific literature on neoliberalism and its consequences for environmental degradation and environmental mobilization. Overall, our findings provide support for threat-based models of mobilization and hold significant implications for research on environmental organizations.