New and Historical Plant Introductions, and Potential Pests in the Juan Fernandez Islands, Chile

In 1935 the Juan Fernandez Islands in the Pacific Ocean were declared a Chilean National Park to protect the unique flora and fauna, and later given status as a Biosphere Reserve by IUCN. Exotic plants deliberately and inadvertently introduced are threats to the natural vegetation. We review the introduced and/or adventitious flora of the archipelago in this paper. We report 21 recent arrivals, eight earlier introductions from the mid-1700s to the 1900s that have not been recognized before in the flora, six misidentified taxa, and five taxa present earlier but now reported from another island, resulting in a total of 227 introduced and naturalized species. Each species is discussed briefly with its native distribution, uses, first arrival in Chile and/or the archipelago, and comments on conservation impact. Identities of some previously cited taxa are clarified (e.g., Cupressus macrocarpa appears to be a misidentification for two other species of the same genus). Other noxious weeds known worldwide have recently been deliberately introduced, especially as garden ornamentals. Two of the most serious potential pests are the bird-dispersed Lantana camara and Lonicera japonica. We recommend immediate eradication of these two taxa and restriction on reintroduction. A conservation program emphasizing strong physical and biological methods is urgently needed to control the introduced species