A new lowland locality for the mountain plant Streptopus amfexifolius (L.) DC. (Silesian voivodeship, Southern Poland)

The occurrence of mountain plant species in the Polish lowlands has been at the centre of attention of many botanists. In 2008-2011 we carried out field studies aimed at describing a new lowland population of White Twisted-stalk S. amplexifolius discovered in 2008. We focused on the following aims: to determine the current status of the lowland population of S. amplexifolius; to characterize phytocenoses and habitat conditions in which the species occur; to identify factors that can potentially pose a threat on the population and to propose guidelines for its protection. The newly discovered population is located in the Trójca Forest District (50º 38.737’ N; 18º 48.945’ E), forest department 61L. The main part of the population (ca. 70%) occupies an area of approximately 100 m2. Currently, to protect the population from grazing, the whole area (about 0.25 ha) has been surrounded by metal mesh fence. The population occurs within a poorly developed patch of Fraxino- Alnetum. It contains 107 branched and fruiting individuals of S. amplexifolius and 83 smaller plants (branchless and sporadically fruiting). The number of fruits per plant varies between 6 and 20. One fruit contains an average of 5 seeds (a maximum of 12 seeds and a minimum of 3 seeds per fruit). The occurrence of numerous Padus serotina seedlings and young plants is recorded within the site. Human-related factors have caused substantial changes in the water relations and, subsequently, also in the species composition of these plant communities. The population of S. amplexifolius within the described site seems to be in good condition and develops normally