Zs. P. Komáromy szerk.: Studia Botanica Hungarica 13. 1979 (Budapest, 1979)
Szerdahelyi, Tibor: Rare ferns of Hungary, I. Botrychium virginianum (L.) Sw. var. europeum Angstr. in the Kiskunság National Park
B. virginianum grows together with Rhamnus catharticus and Geranium Robertianum in two cases, and with Carex spicata ssp. Lumnitzeri , Thalic- trum minus , Muscari racemosum and Aegopodium podagraria in one case. In Table 3 and 4, the estimated values of the species coverage, and also the diversity values (H* ) of the various samples and of the individual species are to be found. The minimum is shown by sample No. 3. Two species, viz. Robinia pseudo-acacia and Bromus sterilis , are dominant here. The coverage values of the other species are small, and this even refers to that of Viola cyanea, although this occurs with high coverage values elsewhere. The maximum values can be found in sample No. 7. The proportion of Bromus sterilis is considerably smaller here. Although the coverage value of Robinia pseudoacaica is high, the other species have quite considerable values as well. B_. virginianum is also present in this sample. Of the diversity values by species, the greatest belong to the three dominant species, viz. Robinia pseudo-acacia , Bromus sterilis and Viola cyanea . Table 4. Cover values and H*, J, N, S values according to samplings Cover value % 1 2 3 4 5 6 7 8 9 10 N 190. 2 254.0 185.7 256.3 229.5 249.6 189.4 250.9 291.2 315.2 S 11 11 14 11 13 14 15 11 10 6 H' 2.0189 2.1288 1.4922 1.6964 2.2481 2.2492 2.4031 2.3349 2.0498 2.1324 J 0.5836 0.6154 0.3919 0.4904 0.6075 0.5907 0.6151 0.6749 0.6171 0.8249 In the case of Crataegus monogyna , Rhamnus catharticus , Geranium Robertianum and Geum urbanum the diversity values are also relatively high. The lowest diversity value is reached by Sambucus nigra . By studying further habitats, and with more data, a more accurate picture of B. virginianum will be available. Here I should like to express my thanks to Julia SzujkóLacza, Director of the Botanical Department, for her kind help in the necessary methods to be used.
