Schaffhausens emblematische Art Potentilla micrantha DC. – ihre Verbreitung 1915, 1943 und 2017

Abstract

The emblematic species of the Canton of Schaffhausen: Potentilla micrantha DC. – its distribution in 1915, 1943 and 2017. Potentilla micrantha DC. (pink barren strawberry) is a characteristic plant species of the xeric flora of the Canton of Schaffhausen (Switzerland) and is currently growing in a wide variety of habitats, mainly in forests, at forest edges or along forest paths and roads. Due to the well-studied flora of this canton, the reconstruction of the historical distribution of P. micrantha was achieved for the time periods around 1915 and 1943, and was then compared with the present species distribution based on an actual survey (2013–2017). The overall distribution of P. micrantha in the Canton of Schaffhausen changed little during the past century. Given the historical records from 128 precisely located sites, 73.4 % of these sites also harboured current occurrences of P. micrantha, while the species was extinct at the remaining localities (26.6 %). Only 14 new locations of the species were detected. However, the species lost a few former occurrences at the distribution limits, and the number of occurrences in or close to human settlements has clearly diminished.