The report is about cultural relict plants – which are remaining populations of plants once introduced or cultivation and used as food, spice and medicine, fibres, colours, or other purposes. Such plants are often regarded as weeds, but they are rather part of a biocultural heritage. Some plants can be part of a place’s history and identity. The main part of the report is given to Bernt Løjtnant’s list of species and the inventories he has done on 100 Danish medieval locations as well as a red list of cultural relict plants in Denmark (in Danish text). The report also includes chapters on relict plants in other Nordic regions and NordGen’s collection missions and conservation efforts as well as a discussion of challenges and future perspectives related to conservation of such plants.