Remarks about the diversity of mountain Norway spruce forest in the Sudetes, with particular reference to the Szczeliniec Massif (Stołowe Mts, Poland)

Abstract: Between 2011 and 2012 from all sites in the Sudetes on which Calamagrostio villosae-Piceetum has been reported so far, 56 relevés were collected according to Braun-Blanquet approach. Collected material enabled us to compare the floristic compositions of the Norway spruce forests from the Karkonosze Mts, the Śnieżnik Massif, the Orlickie Mts, the Izerskie Mts, Wielka Sowa Mt. and the highest part of the Stołowe Mts. The results of
analyses revealed that the area of Calamagrostio villosae-Piceeteum is limited to the highest part of the Sudetes and the association is well developed only in the Karkonosze Mts and the Śnieżnik Massif, with exception of single locality in the Izerskie Mts (the Płonka stream valley). The diagnostic species of this association are Homogyne alpina, Plagiothecium undulatum, Sorbus aucuparia var. glabrata, Rumex alpestris, Athyrium distentifolium, Polygonum bistorta, Gentiana asclepiadea and the differentiating species are Trientalis europaea, Polytrichum commune, Deschampsia caespitosa and Nardus stricta. The rest of earlier described localities of high-mountain Norway spruce forest (including the Szczeliniec Massif in the Stołowe Mts) probably belong to two separate associations: to the acidophilous Vaccinio
vitis-ideae-Abietetum, with occurrence of Abies alba, Betula pubescens agg. and Vaccinium vitis-idaea and to the mesotrophic Luzulo luzuloidis-Abietetum with higher abundance of Fagus sylvatica, Melandrium rubrum, Senecio ovatus and Rubus idaeus. It suggests that the phytocoenoses which have been classified so far in Poland as Abieti-Piceetum (montanum) Szaf., Pawł. & Kulcz. 1923 em. J. Mat. 1978 should be divided into two separate
associations.