Understanding plant significance across cultures and borders is a driving goal in ethnobotany. Often, empirical studies aim to highlight and explain variation in plant knowledge and uses between communities across national, geographic, and cultural boundaries. However, such studies underinvestigate commonality of values and practices between communities. In this cross-border study of highland pastoral communities in both Caucasian Georgia and Turkey, we propose and implement an approach that synthesizes Cultural Importance (CI) and Identified Cultural Importance (ICI) indices. We label this method a “Unified Cultural Keystone Species (UCKS)” approach. We demonstrate that such an approach is uniquely capable of perceiving shared Traditional Ecological Knowledge (TEK) and practices across cultures and borders. Our results identify three primary Cultural Keystone Species (CKS) that cut across cultural and political boundaries in the Western Lesser Caucasus. We argue that these findings allow for a more comprehensive understanding of ethnobotanical knowledge and practices in the study area. This, in turn, can enhance conservation and restoration strategies in the study region and beyond by highlighting the breadth of biocultural knowledge and value held within shared traditions and landscapes. By so doing, we show a way to heighten scientific perceptions of the importance of cultural and linguistic connections to environmental well-being in specific places.