Archaeobotanical studies were carried on during the excavation or trial trenching of 68 rural settlements located on motorway and railroad tracks in Picardy. It allowed reconstructing the main changes that occurred in crop husbandry practices and dietary habits, from the late Bronze Age until early middle Ages. Cereals represented the staple crops and the proportions of the main species: six-row barley, emmer, spelt and naked wheat (bread wheat / durum wheat), varied through time. After the Roman conquest, two areas could be distinguished on the basis of their productions and breeding practices that differ greatly from one side of the region to the other. In southern Picardy naked wheat was especially present whereas to the north of the River Somme, the cultivation of hulled wheat was still dominant, and spelt wheat represented the main crop. Cereals were not the only resources; the beginning of fruit cultivation is also dated to the early decades of the historical periods.