Crepis bursifolia L. (Italy) – A very rare alien. A single individual was discovered as a pavement weed in the city of Menen in 2016, very close to the French border. In 2020 the species was also discovered in Koksijde. About 20 individuals are growing on a semi-paved private parking lot, near to the coastal dunes.
Crepis bursifolia originally has a very limited distribution area in Sicily and parts of continental Italy. However, since the 20th century it started expanding further north. It now occurs in many parts of France (Duvigneaud & Lambinon 1976, Tison & de Foucault 2014) and recently reached Lille in northwestern France (Tela Botanica). The latter populations are very close to the Belgian frontier and may explain its occurrence in our country. Alternatively, its locality in Menen being next to a garden center (where large containers with olive trees from southern Europe are offered for sale), it may also have been introduced via the horticultural trade (e.g. Hoste & al. 2009, Hoste 2013).
Crepis bursifolia is a fairly distinct species: the combination of runcinate rosette leaves, the absence of stem leaves and achenes with very long beaks (up to twice as long as body) separates it from all other Belgian representatives of the genus.
Crepis bursifolia is a perennial and often considered weedy, outside of Europe for instance in California in the U.S.A. (Bogler 2006).
Bogler D.J. (2006) Crepis. In: Flora of North America Editorial Committee (eds.), Flora of North America, vol. 19. Oxford University Press, New York-Oxford: 222-239. [available online at: http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=108351]
Duvigneaud J. & Lambinon J. (1976) Quelques mots sur la distribution de Crepis bursifolia L. (Asteraceae). Soc. Ech. Pl. Vasc. Eur. Occid. Bassin Medit., Bull. 16: 89-90.
Hoste I. (2013) Olijfbomen, palmen en tuincentra: een inleiding tot de containerfloristiek. Dumortiera 102: 10-16. [available online at: http://www.br.fgov.be/DUMORTIERA/DUM_102/Dum_102.pdf]
Hoste I., Verloove F., Nagels C., Andriessen L. & Lambinon J. (2009) De adventievenflora van in België ingevoerde mediterrane containerplanten. Dumortiera 97: 1-16. [available online at: http://www.botanicgarden.be/DUMORTIERA/DUM_97/Dum%2097_1-16_Mediterrane%...
Tison J.-M. & de Foucault B. (coord.) 2014) Flora Gallica. Flore de France. Editions Biotope, Mèze : xx + 1196 p.