In two experiments of five years duration there was studied the influence of covering the soil with layers of black foil among the trees in the young orchards: in the apple tree one – of the species Elstar Elshof on M9 stock and in the cherry one – of the species Łutówka, on the seedling of antypka (Prunus Mahaleb) on enzymatic activity and chemical properties in the pedone of the typical fallow soil (Haplic Luvisols). The control object was a herbicide fallow among the rows of trees. The experiments took place in the experimental orchard of the Orchardry Department of Agriculture Academy in Lublin. In the fifth year of the experiments, a manifold influence of the black foil on the soil environment was proved. A clearly unfavourable influence of covering the soil among the rows of trees with the black foil on the biochemical and chemical properties of the soils in the above-mentioned experimental orchards was observed in the level Ap, exclusively. The phenomenon was not observed in the deeper genetic levels of the soil (Eet and Bt). In both orchards the soil covered with the layer of black foil was characterised by a higher average activity of all the studied enzymes than the soil of the herbicide fallow. In the level Ap, the enzymatic activity in the soil under the layer o f the b Jack foil was lower, while in the level Eet and Bt it was higher than in the soil o f the herbicide fallow. The cherry orchard soil was in fact characterised by a higher enzymatic activity than the soil of the apple orchard. The results confirm once again that the enzymatic tests monitor the changes, which take place in the soil under the influence of the cultivated plant.