Plant exchange networks in the 19th century – 200 years of citizen science

Abstract

Plant exchange networks in the 19th century have been investigated in a largescale study, firstly by identifying as many plant exchange organizations (PEOs) as possible and secondly by searching for exchange partners in a 19th century private herbarium from Southwest Germany, and by analysing exchange activities related to the rare central European endemic Saxifraga rosacea subsp. sponhemica (C.C.Gmel) D.A.Webb. In this paper a first overview on selected results is given: 101 PEOs – founded from 1819 to 1947 – with a total of 3000 to 5000 members have been found; they distributed 15 to 20 million specimens; 111 collectors have been identified in the exemplary private herbarium, from which specimens have been found in 27 herbaria; S. rosacea subsp. sponhemica has been collected by 242 individuals, 233 exchange partners received duplicates distributed by 12 PEOs.