Evaluating prehistoric finds of Arrhenatherum elatius var. bulbosum in north-western and central Europe with an emphasis on the first Neolithic finds in Northern Germany

The swollen basal internodes of the grass species Arrhenatherum elatius var. bulbosum (tuber oat grass) are recorded here for the first time for Neolithic Germany. These charred bulbs occurred in the Late Neolithic soil mantle of the megalithic tomb of Albersdorf-Brutkamp LA 5. They are interpreted as most probably originating from the natural vegetation on and around the grave mound. The bulbs were possibly charred in the course of a ritual fire. However, their use as gathered plants and their intentional deposition in a secondary burial ritual during the Late Neolithic cannot be excluded with any certainty. Identification criteria for Arrhenatherum bulbs as well as the ecological requirements of the species are introduced here. Furthermore, prehistoric bulb finds from north-western and central Europe, and different interpretations concerning the occurrence of Arrhenatherum in different archaeological contexts, are discussed. The compilation of finds from literature and excavation reports shows that bulbs of Arrhenatherum were found rather infrequently in the Neolithic. Most commonly, charred bulbs of A. elatius var. bulbosum are detected in Bronze Age cremation graves. In the Iron Age, however, they mainly occur in domestic sites. This shows that the interpretation of the plant remains is dependent on their archaeological context. A ritual meaning of the bulbs has to be considered in the interpretation, but they may also have contributed to people’s daily diet. This evaluation of bulb finds in prehistoric and historic contexts contributes to the debate on the relevance of plant gathering in early economies and in ritual activities.