L. Lőkös szerk.: Studia Botanica Hungarica 24. 1993 (Budapest, 1993)

Stollmayer-Boncz, Emilia: The flora of Réti-dűlő near Csömör

The majority of the protected area comprises meadows where most of the plants in need of protection occur. The greatest number of species (19) falls into the "very wet" group (W=9). Species classified as "wet" or "moderately wet" (W=7 and W=8) are also numerous, 16 and 17, respectively. 11 species were assigned to categories "damp" (W=5), "moderately damp" (W=4), and "moderately dry" (W=3). Species of the last group occur on the few, small, elevated parts of the area as well as in drier segments close to the road. Reeds and brookside habitats are naturally dominated by species belonging to the group W=9. The dry roadside area and the locust forests are inhabited by species overwhelmingly of the group W=3. The protected species belong to categories W=7-10. The wet habitats allow the survival of these plants amidst the surrounding cultivated land. Using the Nature Conservation Ranks (NCR) of Simon, half of the plants occurring in the area is natural and half is indicative of degradation. For a more accurate evaluation of degradation, 30% comprised by disturbance-resistant species (TZ) should be discounted, as most of the area is hay field (Fig. 7). (Their average ratio in the flora of Hungary is 40% to 60%). Due to the different vegetation of particular units, it is meaningful to analyze the distribution of NCR categories separately, similarly to the study of W values (Fig. 8). Obviously the locust forest and the roadside show most signs of degradation (76-80%). The percentage of natural and degraded constituents of the meadow flora is similar to the overall mean value of Hungary (58% and 42%, respectively). Edificator (E) and accompanying (K) species have a higher representation. The share of disturbance-resistant species (TZ) are significantly higher, due to the hay field use of the area. There are no unique (U) and natural pioneer (TP) elements; the percentage of strictly protected (KV) and protected (V) as well as the cultivated (G) and adventive (A) plants is lower than normal in Hungary. To obtain a more realistic picture, relative abundance of species was also taken into account in the evaluation (Fig. 9). The ratio of natural and degraded species is 65% to 35%. This is in accordance with the natural landscape pleasing to the eyes. The protected plants (7%) and the edificator plants are reasonably well represented (10%), whereas the share of accompanying species is outstanding (48%). The high proportion of disturbance-resistant species (27%) together with the common accompanying elements are indicative of a healthy wet hay field assemblage. The area "requires" mowing to prevent overgrowth by willow bushes. The mowing in May is unfavourable for the orchids. They can only bring seeds at the edge of reeds or the wet spots of the meadow with reedy patches. Parnassia palustris is fortunate because of its small size and late flowering. Iris pseudacorus cannot bring flowers in the small patch where it grows. Mowing in late September or in October would be more advantageous for Carex appropinquata and Eriophorum latifolium to reach greater number of specimens. The reeds are characterized by a large number of accompanying species. 62% of the floral elements are natural. The brook bank is dominated by accompanying, disturbance-resistant, edificator, and weed species. The evaluation of some habitats require further studies. A quantitative survey has been carried out in the meadow only. Further such work is being conducted and planned for the future. Upon completion, a more precise assessment of the assemblages of the area and the production of a vegetation map will be possible. The area can best be characterized by delineating the abundant and common species of each habitats (Table 1). The vegetation of the locust forest and the roadside serves as a buffer between the cultivated fields and the meadows and reeds. Thus these two areas also deserve a brief treatment. Abundant species of the locust forest include Robinia pseudo-acacia (G) which forms the canopy level, the soft-stemmed, fragrant Anthriscus cerefolium subsp. trichospermum (TZ), and Bromus sterilis (GY). They account for the high ratio of degraded species in the locust forest. There is a large number of common species; dicotyledons include Alliaria petiolata (TZ), An33