- To display the role of non-crop areas (including abandoned fields) in the establishment of ragweed populations by studying Central-Hungarian sampling areas;
- To demonstrate the effect of land-use types and cultivation methods on the presence of ragweed in the vegetation and in the seedbank;
- To study by experiment the effect of seed-bank size, the soil disturbance, nutrient supply and the land use type on the number and size of ragweed individuals.