Аннотация:The influence of the initial cultivation degree on the development of modern soil-forming processes during the four-year period of overgrowing of agro-soddy-podzolic loamy soils and their development under arable land was studied. The object of the study was the arable layer of agro-sod-podzolic soil of different initial levels of fertility and type of use. Based on the data of long-term field experience, the influence of the initial cultivation degree on the development of modern soil-forming processes over the period of four-year overgrowing of agro-sod-podzolic loamy soils and their development by arable land, which led to a change in their agrochemical indicators, was established. It was shown that the overgrowing process caused the differentiation of the arable layer into two subhorizons. The soddy process of soil formation due to the decomposition of grassy weeds in it is superimposed on its upper part (0-10 cm), which leads to an increase in the content of organic matter and the amount of exchange bases in this subhorizon. The zonal podzolic process, which causes a decrease in its high humus content and an increase in acidity, begins to superimpose on the lower part of the arable layer (10-20 cm). Increased and high initial cultivation accelerates the differentiation process of the post-agrogenic horizon into sublayers. The plowing of the post-agrogenic horizon eliminates the emerging differentiation during the first year of development of the fallow lands. The plowed post-agrogenic horizon differs from the arable layer of similar agro-sod-podzolic loamy soils with a higher acidity and increased organic matter content (by 0.06-0.10 abs.% or 3.3-4.8 rel.%). The levels of cultivation of the arable horizon created in previous years are preserved even in the fifth year of observations.