A field study was carried out to estimate the variations in the concentrations of macro- and trace elements in the rhizosphere soil and in roots and leaves of three widely distributed plant species-couch grass, plantain, and yarrow collected simultaneously from two sites characterized by different soil parameters. Main attention was paid to environmental (soil characteristics) and phylogenetic (plant species) factors that can influence on the concentrations of different elements in the plants and in soils. Both the factors cannot be considered as independent, although their contribution to the plant elemental composition may be different. There were statistically significant differences between concentrations of C, N, and H and 13 macro- and trace elements in the soils collected from the two sites. The concentrations of many chemical elements in the rhizosphere soil of the three plant species collected from the same site were often different. The differences in the characteristics of the soils at the sites resulted in differences between the concentrations of several elements in the plants growing at the sites. However, this was only one of the reasons of significant difference between the concentrations of macro- and trace elements in the same plant species collected from the sites. Couch grass, plantain, and yarrow had different reactions on the soil characteristics. The elemental composition of each plant species was unique although they grew at the same place and were collected simultaneously. Among the plants, yarrow was more tolerant to varying environmental conditions than plantain and couch grass.