Brassica barrelieri (L.) Janka (W-Medit.) – An exceptional and ephemeral alien. Recorded only once, in 2013, on rough ground near a grain storage in the Roeselare port area.
Brassica barrelieri apparently is a rather rare alien in Europe. In the British Isles there are only historical, no recent records (Clement & Foster 1994). In France it is naturalized and expanding in the Beaujolais region (Cornier & Girod 2002, Munoz 2003, Tison & de Foucault 2014). It is a noxious weed in parts of Australia as well (numerous online references).
This species is reminiscent of B. tournefortii. It has, however, bright yellow petals and very typical runcinate-pinnatifid rosette leaves that are tightly appressed to the soil; the leaves usually have more numerous lateral leaflets.
Selected literature:
Clement E.J. & Foster M.C. (1994) Alien plants of the British Isles. BSBI, London: XVIII + 590 p.
Cornier B. & Girod C. (2002) Brassica barrelieri (L.) Janka (Brassicaceae), plante nouvelle pour la France naturalisée dans le département de la Loire. Bulletin Mensuel de la Societe Linneenne de Lyon 71(2): 75-88. [available online at: https://www.researchgate.net/publication/235339775_Brassica_barrelieri_L...
Munoz F. (2003) Une nouvelle station de Brassica barrelieri (L.) Janka (Brassicaceae) dans la région lyonnaise. Bulletin Mensuel de la Societe Linneenne de Lyon 72(7): 247-248. [available online at: https://www.researchgate.net/publication/253954529_Une_nouvelle_station_...
Tison J.-M. & de Foucault B. (coord.) (2014) Flora Gallica. Flore de France. Editions Biotope, Mèze : xx + 1196 p.