The paper presents the results of researches that were done during 2003-2005 period, on the experimental field of Agrotehnics from Cluj-Napoca, whose objective was to establish the weed characteristics from the crop rotation: autumn wheat - potato – maize – soybean and its fluctuation by the crop rotation. The weed level from the rotation is followed in terms of flourish spectrum composition aspect, species frequencies, species ponderosity and the achieved covered degree. It is appreciated the crop rotation of its contribution to rationalize the technologies of these four crops through the crop rotation, and also to assure the premise of durable capitalization and the zone resource and the elimination of the risk of the agroecological possible derangements in the situation of omission of the rational weed control importanc
