Plants used in basketry production during the Early Neolithic in the north-eastern Iberian Peninsula

Plant-based artefacts are rarely preserved in archaeological contexts in the Iberian Peninsula. Very few sites with specific conditions such as waterlogging, aridity or carbonization have preserved organic material. The aim of this paper is to establish an identification criterion for identifying organic raw materials used for manufacturing plant-based artifacts by using optical microscopy. The coiled basketry remains found in La Draga (Banyoles, Girona) and Coves del Fem (Ulldemolins, Tarragona) have been studied using this method. The materials were exceptionally well-preserved by waterlogging in the case of La Draga, and carbonized or dehydrated in Coves del Fem. Samples of both coils and stitches from all the basket remains were analysed. The anatomy of their cross-sections was observed under a transmitted light bright-dark field (BF-DF) optical microscope and compared with modern reference collections. The results show the use of at least five species corresponding to four families: three monocotyledons (Poaceae, Cyperaceae and Typhaceae) and a dicotyledon (Malvaceae). Moreover, it has been possible to distinguish the part of the plant used. Variability in raw materials implied extensive environmental knowledge. Moreover, functional studies of wooden, faunal, lithic and malacological tools suggest a local production of baskets. This paper expands the current knowledge of raw materials used for basketry purposes during prehistory in the Mediterranean area as the examples from La Draga and the Coves del Fem are the oldest basketry remains that have been studied in depth in the Iberian Peninsula and Europe.