Acta Scientiarum Polonorum
Silvarum Colendarum Ratio et Industria Lignaria

Abstract The dendroflora of the “Olszak I, II” ecological site includes 108 taxons from 25 families. Tree stands are dominated by stands with Pinus sylvestris and Betula pendula but there are also significant numbers of deciduous bushes and trees associated with oak-hornbeam forests, flood plain forests and alder forests. Stand fragments with species composition closest to the natural one can be found in flood plain forests, alder forests and oak-hornbeam forests, primarily in the valley of the Cybina River and the adjacent areas. Although the dendroflora of this land is under a strong anthropogenic pressure, it should be considered as one of the most valuable dendrofloric objects in Poznań. We can find here 4 species under legal protection, 7 species from the regional red list, 20 plants from the list of threatened species in Poznań and 76 trees selected for protection as monuments of nature.