Linearbandkeramik (LBK) pottery, lithic industries and architecture are well known. Paradoxically, there have been relatively few studies either of the vegetation in areas where the first farmers of Middle-Belgium settled at the end of the 6th millennium BC or of their plant economy. Charcoal, carbonized seeds and fruits of nine LBK sites in Middle-Belgium are analysed. There are at least two phases of occupation in the region. The first settlers exploited the main components of the oak and ash forest : oak, ash and hazelnut. During the second phase, gathering of firewood was more diversified and concentrated on the forest edges which were composed of Prunoideae, elder and especially Pomoideae (hawthorn, apple tree…). Thus both phases could be distinguished by their charcoal assemblages, as well as by specific ceramic and lithic artefacts. Charcoal analysis provides good evidence for the relative chronology of LBK sites in Middle-Belgium and indicates a particular mode of forest exploitation during this period. The main cultivated plants come from the Near East : hulled wheats (emmer and einkorn), legumes (pea, lentil) and flax. The opium poppy is well established in north-western Europe at the end of the 6th millennium BC and it has generally been considered that the plant comes from the Mediterranean. However, finds of poppy older or contemporary with the LBK are scarce in the west Mediterranean zone, suggesting that this consideration should be revised. Analysis of seeds and fruits points to a homogenous farming economy from the Rhineland to the Paris basin during the LBK period, as well as revealing extra-cultural contacts and some regional particularities involving the principal cultivated cereals. ; De nombreux chercheurs étudient la culture rubanée dont les traditions céramiques, lithiques et architecturales sont aujourd’hui bien connues. Paradoxalement, le milieu végétal dans lequel arrivèrent, vers 5200 av. J.-C, les premiers agro-pasteurs sédentaires d’Europe nord-occidentale, ainsi que leur économie ...