Investigations were conducted at five oak experimental areas, established in 1952, 1968 and 1995 as mixed, nest and row croplands in the surface of complete clearance. It was found that in each of the areas the species composition and the size of the populations of individual species of mites differed. However, the dominant mite species in the pine area still remain dominant in experimental areas, although at different proportions. It suggests that probably mites primarily migrated from the neighboring pine tree stands to the newly established experimental areas. Moreover, it was shown that in the pine area the percentage of mites from the family Parasitidae was definitely the highest and the imbalance between the percentage of mites from the family Parasitidae and those from the suborder Uropodina was the biggest. On the other hand, in the experimental oak tree stands the populations of species did not differ so much in size.

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