Risk prioritization of bamboo species in the EPPO region

Bamboos are popular ornamental plants in the EPPO region though some of them have been observed to escape the confines of planting and establish in the natural environment. The aim of this study is to produce a risk-based list of bamboo species which are recorded in the natural environment in the EPPO region, and to determine if any of the species require a pest risk analysis. Forty-two bamboo species were identified as being present in the natural environment in the EPPO region. Of these, 11 species fulfil the three pre-selected criteria for species to be considered potentially harmful: (1) the species is naturalized in at least one EPPO country; (2) the species has a running dispersal behaviour (leptomorph); and (3) there is evidence of invasive behaviour in at least one country. These 11 species were prioritized using the EPPO prioritization process for invasive alien plants. Owing to their high spread potential and potential high impact, three species, namely Phyllostachys aurea, Pseudosasa japonica and Sasa palmata, proceeded to the second stage of the prioritization process (risk management stage). All three species were identified as having a high priority for a pest risk analysis. In 2024, the EPPO Panel on Invasive Alien Plants agreed with the results of the study but noted that further information on impacts would be beneficial and therefore the Panel agreed that Ph. aurea and S. palmata should be added to the EPPO Alert List along with the already included P. japonica. This will raise awareness of these species in the region and further information can be gathered to support the development of a risk assessment.