The article is devoted to solving the problem of re-compaction of agricultural soils. The positive effect of growing six species
of perennial grasses has been shown: sowing alfalfa, meadow clover, sand sainfoin, white clover, horned clover, eastern
goatskin on the creation of an optimal bulk soil mass. The indicated indicator in the dynamics of the four-year period of
growing leguminous perennial herbs is analyzed. The minimum period for growing leguminous perennial herbs has been
established for which it is possible to achieve a stable and favorable bulk soil mass. The factors providing the optimal soil
density during the cultivation of certain types of herbs, including the parameters of the root systems, soil cultivation and
weather conditions, are justified. Based on the studies, a technology was developed to optimize the volumetric mass of the
soil by selecting certain types of perennial leguminous herbs and the timing of their cultivation. The ability to optimize the
bulk soil mass at the level of 1.13 – 1.18 g/cm3 for the third or fourth year of vegetation of leguminous perennial grasses
has been proved.
Іn the year of sowing of leguminous perennial grasses, the volume of soil mass depends largely on the basic tillage of the
grasses under sowing and is determined by the magnitude and nature of precipitation. Since the second year of vegetation
of leguminous perennial grasses, the bulk mass of the soil is determined by the peculiarities of propagation in the soil of the
root systems of different types of grasses. There is a tendency to decrease the volume of soil under the legume of perennial
grasses in the second year of their vegetation, followed by an increase in the third year and stabilize – in the fourth year of
vegetation of grasses at an optimal level for the growth and development of cultivated plants. Among the perennial grasses,
the soil of alfalfa is sown best, and the worst is sand asparagus.