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The water chestnut (Trapa natans L.) as a food resource during the 4th to 1st millennia BC at Lake Federsee, Bad Buchau (southern Germany)

Abstract During archaeological excavations at several wetland sites around Lake Federsee, remains of water chestnut were detected. The finds are dated to between the 4th and 1st millennia BC. Until recently the starch-containing nuts of water chestnut were used for human nutrition in Europe. The nuts can easily be harvested in autumn. Pollen and plant macrofossil remains from several sites are proof of a wide distribution during the Holocene, probably influenced by humans. Nowadays this annual water plant is extinct in many parts of Europe. The growing conditions of water chestnut are strongly restricted with regard to water quality, depth and temperature, and therefore finds of this plant have the potential to allow reconstruction of former ecological conditions.