The ancient levels of the site of Nesle/Mesnil-Saint-Nicaise (Somme) are characterized by installations connected with cultual practices. Areas with ash deposits and the bottom of a well have yielded remains that help to determine, on the one hand, the species exploited, and on the other hand the vegetal environment of the site in the 1st and the 3rd centuries A.D. The multidisciplinary approach (cross-referencing anthracology, archaeozoology, carpology, palynology, xylology) presents an environment of trees certain species of which are strikingly rare. Traduction : Margaret & Jean-louis CADOUX