While the current consumption of wild food plants in the taiga of the American continent is a relatively well-researched phenomenon, the European taiga area is heavily underrepresented in the scientific literature. The region is important due to its distinctive ecological conditions with restricted seasonal availability of wild plants. During an ethnobotanical field study conducted in 2018-2019, 73 people from ten settlements in the Republic of Karelia were interviewed. In addition, we conducted historical data analysis and ethnographical source analysis. The most widely consumed wild food plants are forest berries (three Vaccinium species, and Rubus chamaemorus), sap-yielding Betula and acidic Rumex. While throughout the lifetime of the interviewees the list of used plants did not change considerably, the ways in which they are processed and stored underwent several stages in function of centrally available goods, people's welfare, technical progress, and ideas about the harm and benefit of various products and technological processes. Differences in the food use of wild plants among different ethnic groups living in the region were on the individual level, while all groups exhibited high variability in the methods of preparation of most used berries. The sustainability of berry use over time has both ecological and economical factors.