First report of Senecio brasiliensis naturalised in Europe
Senecio brasiliensis (Asteraceae) is an erect glabrous herbaceous perennial (100-200 cm tall) native to South America (Argentina, Bolivia, Brazil, Paraguay and Uruguay). Outside its native range it has been recorded in the United States (Florida but no longer present) and it was recorded as a casual in the United Kingdom in the second half of the 19th century. A naturalized population of S. brasiliensis was recorded in the Matosinhos port area (Porto district, Santa Cruz do Bispo, Portugal) in May 2017. This is the first time a naturalised population of this species has been recorded in Europe. Seedlings, juvenile and adult flowering and fruit-bearing individuals were present. In 2017, 10–20 individuals were recorded in several habitat types, specifically hygrophilous woodlands, in the fringe of mixed plantations and on disturbed ground dominated by small shrubs, perennial grasses and forbs. In 2018, the hygrophilous woodland was clear-cut and the number of S. brasiliensis individuals increased to 50 or more specimens. The authors hypothesise that the most likely pathway of entry is via seed material contaminating imported wood material. The port receives shipments of logs of eucalyptus imported from Brazil and Uruguay. Climatic matching between the native range of the species and Europe shows that over 25 % of Europe has climatic conditions that are compatible with the requirements of the species. This includes areas in 14 countries: Albania, Bosnia-Herzegovina, Bulgaria, Croatia, Cyprus, France, Greece, Italy, Macedonia, Montenegro, Portugal, Slovenia, Spain and the United Kingdom (England). The authors conducted a risk assessment on the species using the Australian Weed Risk Assessment System (RS 2008/113) and concluded the species should be considered as a high risk as the results of the risk assessment give the species a score of 18 (any score over 6 highlights potential invasiveness). Control measures should be implemented against S. brasiliensis in Portugal and further surveys should assess if there are additional satellite populations in the wider vicinity.
Sources
Dana ED, Verloove F, Alves P, Heiden G (2021) Senecio brasiliensis (Spreng.) Less. (Asteraceae), another potentially invasive alien species in Europe. BioInvasions Records 10(3), 521–536. 536, https://doi.org/10.3391/bir.2021.10.3.02