Misidentification of Gunnera plants
Misidentification and incorrect labelling of ornamental plants can lead to the movement of invasive alien plants (RS 2022/094). The genus Gunnera (Gunneraceae) comprises 63 species mostly distributed in the Southern Hemisphere. In the EPPO region, two species have been present in horticulture: Gunnera tinctoria (EPPO List of Invasive Alien Plants) which is regulated as a species of Union concern (EU Regulation 1143/2014) and banned from sale, and G. manicata which is not regulated, and it is traded. Both species are similar in form and flower only after numerous years therefore major distinguishing characters to tell the two species apart are missing when in trade. Molecular and morphological studies were undertaken on Gunnera plants in trade, from botanical gardens and from wild populations (native populations and invasive populations from New Zealand and Ireland). The results showed that the plants in Western Europe and New Zealand which are considered to be G. manicata are hybrids with the mother plant being G. manicata and the father plant G. tinctoria. Gunnera plants in horticulture in Western Europe are predominantly mislabelled as G. manicata but many are actually G. tinctoria.
Sources
van Valkenburg JLCH, Osborne BA, Westenberg M (2023) The large Gunnera’s (G. tinctoria and G. manicata) in Europe in relation to EU regulation 1143/2014. PLoS ONE 18(4), e0284665. https://doi.org/10.1371/journal.pone.0284665