Abstract: This paper deals with the relationship between soils and mean annual Increment single poplar tree in the vast plain of eastern China. According to the climate, the geomorphy, the parent materials, and the groundwater level, soils of this region may be divided into ten types. The sequence of their fertility is as follows: grey fluvo-aquic soil, red clayed fluvo-aquic soil, loamy fluvo-aquic soil, fluvo-aquic cinnamon soil, desaline fluvo-aquic soil, carbonate cinnamon soil, shajiang black soil, saline fluvo-aquic, sandy fluvoaquic soil and solonchak. Compared with the forest soil in mountainous region, the organic matter content and total nitrogen content in all plain soils are poor. Except soil available potassium, most plain soils are also poor in available nitrogen and especially available phosphate. Both in the soil or in the ground water all over the plain the calcium is very abundant, it suits poplar-calciphile very well. The datum of mean annual increment of 16 poplar clones and 3 other broad-leaved tree species in different soils have been given in this paper. According to the results of the former study, it is proved that each poplar species has its own suitable site.