Archaeological features at the multi-culture site of Lutomiersk–Koziówki 3a-c in central Poland contained preserved charred plant macro-remains. The site is located within the “Central European sand belt” characterised by sandy terraces and dunes, nowadays covered mainly by podzols and anthropogenically changed soils. The samples come from pits dated to the Middle Bronze Age (MBA, ca. 18th–14th centuries BC), the Late Bronze Age (LBA, ca. 10th–8th centuries BC), and the Roman Iron Age (RIA). The most intensive occupation was connected with the development of the LBA settlement of Lusatian culture. During that time mostly peas (Pisum sativum) and millet (Panicum miliaceum) were cultivated while remains of large-grained crops like einkorn (Triticum monococcum), emmer (Triticum dicoccum), spelt (Triticum spelta), and barley (Hordeum vulgare) were not common. In that time goosefoot (Chenopodium album) and wild buckwheat (Fallopia convolvulus) were probably used as a source of food. In the Roman Iron Age, the presence of those plants decreased and rye (Secale cereale) appeared, becoming the most common cultivated plant besides barley. The unique find of cocklebur (Xanthium strumarium) seeds in the LBA samples was possibly connected with their useful properties, primarily as medicinal plants and secondarily as a source of oil. The cocklebur remains were probably processed, but no by-products and no whole fruits were noted. The context of these finds is exceptional compared with the other samples from the site, possibly reflecting medicinal activities of the people. Taking into account the history and migration of the cocklebur in Europe during the Holocene, it must be emphasized that the charred seeds from Lutomiersk–Koziówki are currently the oldest radiocarbon-dated finds in Europe (2745 ± 30 BP, ca. 975–818 cal. BC) and can reflect distant contacts of the settlers mostly with south-eastern Europe although eastern routes cannot be excluded as well.
The aim of the study is a presentation of plant macro-remains from the site of Lutomiersk–Koziówki and their exceptional character not only in this poorly studied region but also in a broader European context. The description of plant remains from all periods represented at the site reflects the degree of intensity of human occupation while the comparison of data from the two best-represented periods permits the tracing of changes in plant use.