Plant Introductions: Historical Sketches1

Plant species, their parts and derivatives have been transferred by humans since the beginning of history: unintentionally (e.g., with propagules adhering to clothes) or intentionally (e.g., when species or parts of them were used for food or as sources of tools). Numerous plant transfers resulted in species becoming permanently naturalized in new areas, in some cases with extremely negative effects for the region to which they were brought. However, transfers also often proved neutral or even beneficial. This article does not intend to give a comprehensive survey of the history and the consequences of plant transfers in space and time but presents and discusses illustrative examples of plant movements by people. Special emphasis is given to effects on islands and to historical, political, and economic aspects of long-distance plant trade in the Old World often little known by botanists.