Small-scale, conservation-based agrarianism provides a model for sustainable human habitation within heterogeneous landscapes. Thoreau's Transcendentalism and the historical roots of American Agrarianism are explored as influences for wilderness preservation and the New Agrarian movement. Idealizing a distant wilderness too often means overlooking the ecological and socio-economic environment where people live. Middle landscapes between nature and culture, or between wilderness and cities, can either increase or reduce ecological and social functioning within the landscape matrix. Managing middle landscapes by agrarian principles helps move both nature and culture towards ecological, economic, and social sustainability. This thesis ends with a discussion of agrarian themes, such as supporting decentralized local economies and increasing community connectivity, applied in urban, rural, and wilderness landscapes.