The physical degradation and compaction of the soils are global problems that affect large areas also in Hungary. The preservation of soil fertility is a fundamental aim of economic crop production. Soil compaction can be prevented by the application of regular loosening, or the already formed compacted layers can be eliminated.

The main goals of our research were to quantify the impact of annual medium-deep loosening on soil compaction and to compare the soil status under loosening and ploughing. The measurements were carried out on a compacted soil with high clay content near Karcag. The examined plot was loosened each year during the last decade by a local farmer, while the control plot was a neighbouring one under conventional tillage based on ploughing. The penetration resistance and the soil moisture content values were measured three times and evaluated.

We found that the regular loosening of the soil had favourable effect on its penetration resistance. The annually loosened area showed lower resistance down to the entire 60 cm deep soil layer than in the ploughed soil. In the ploughed plot, a compacted plough pan could be figured out under the regularly cultivated layer, the penetration resistance at the depth of 30 cm reached 8 MPa in spring, while it was almost 10 MPa in autumn time.

On the base of our measurements, we concluded that annual loosening of the soil results in a soil physical status favourable for the crops, while the fuel consumption is not higher but the labour hours are lower compared to conventional ploughing.

Keywords: soil loosening, soil compaction, penetration resistance