The existence of xeric grassland patches in the Lower Oder Valley can be traced back to human economic activity. They were created in the middle ages when, after logging on slopes and on the edges of the valley, pastures were established. In spite of the fact that their development was largely a result of human activity, these grasslands are incredibly rich and interesting habitats, with many (particularly floristic) rarities. Xeric grassland is subdivided according to soil conditions into sandy xeric grasslands (on sandy soil) and pannonic grasslands (on loamy soil).
Sandy Xeric Grasslands can be found throughout the Lower Oder Valley, even in elevated locations of the riparian zone itself. As a result of the flood dynamics, and the alternation of sedimentation and erosion, sandy xeric grasslands also exists on sedimented stretches of sand on the polder. The yellow blossoms of the Petasites spurius are a notable sight there as early as March, while later on, a number of small, rare species of Cerastium (Cerastium dubium, Cerastium pallens, Cerastium brachypetalum) blooms there. In summer, grey-hair-grass (Corynephorus canescens) and Silene tatarica dominate. As these locations become more established, meadows of maiden pink and thrift develop.
In more elevated places there are different types of sandy xeric grasslands, with species of fescue (Festuca trachyphylla, Festuca psammophila, Festuca polesica) being the most predominant among the grasses. Here, several species and subspecies of feather grasses (Stipa joannis, Stipa borysthenica) also occur, and with their long awns are a gorgeous sight in early summer. Rare herbs, such as Silene otites and Silene chlorantha, Hieracium echioides, Carthusian Pink (Dianthus carthusianorum), Orthantha lutea, Campanula sibirica and many more, complete the picture.
From a floristic and conservationist point of view, the Pannonic Grasslands in the National Park are especially notable. While the feathergrass-steppes of Stipa capillata grasses are still relatively monotone, the meadow-steppes near Geesow, Gartz, Stützkow, Gellmersdorf, Stolpe and Stozenhagen are rather reminiscent of blossoming gardens than conventional floristic communities.
Already in early spring, the light blue blossoms of the hairy violet (Viola hirta) create a strong contrast to the yellow blossoms of the Potentilla arenaria, which are soon interspersed with the vigorous white blossoms of the snowdrop anemone (Anemone sylvestris) and the Potentilla alba. As the dominant tor-grass (Brachypodium pinnatum) and the pretty quaking-grass (Briza media) develop, the inflorescences of the Anthericum ramosum, of the blue meadow sage, the blossoms of the different, colorful species of clover (Trifolium montanum, Trifolium alpestre), and the dark blue blossoms of the large self-heal (Prunella grandiflora) open up. The long stems of the Scorzonera purpurea, carrying its purple inflorescences, are complimented by the redish-pink raceme of the three-toothed orchid (Orchis tridentata). Before summer sets in, rare species of Orobranche (Orobanche vulgaris and Orobanche lutea) appear, which are holoparasites, meaning they are bound to specific host-species. Orobranche lutea, for instance, exists only where blue alfalfa (Medicago falcata) grows. Simultaneously, different species of bellflower (Campanula glomerata, Campanula cervicaria, Campanula bononiensis) begin their flowerage, which often lasts until late fall. On the periphery of brush, groups of bloody cranesbill blossoms (Geranium sanguineum) are often plentiful.
Gentiana cruciata, with its dark blue blossoms, inaugurates the height of summer and then signals the advent of the autumn flora. At that point, individual sections of the slopes look yellow, as multitudes of goldilocks aster (Aster linosyris) and goldenrod (Solidago virgaurea) appear, which are then overgrown by the towering Peucedanum cervaria. All this, however, covers only a small portion of the wonderful biodiversity present in these habitats.