Smyrnium olusatrum L. (S Eur., W As., N Afr.) – A very rare alien. Discovered in 2016 in two localities. First seen as an escape from a garden in Heverlee (a few individuals), subsequently also in a roadside of the E40 motorway near Nieuwpoort (a single individual). In the latter locality there is no obvious vector of introduction. However, there is a direct connection between this motorway and the Eurotunnel in Calais. Smyrnium olusatrum being very common on the southern coasts of the British Isles, it is not unlikely that in Nieuwpoort the species was introduced inadvertently by road traffic coming from there.
The status of this species in Belgium is hard to assess, given its recent arrival. However, Smyrnium olusatrum is a very prolific species and sometimes considered invasive. A future naturalization, especially in coastal areas, is likely. This southern species is known since quite some time from the Netherlands (van der Meijden 2005); hence, its appearance in Belgium was more or less predictable. In identical circumstances it was found, also in 2016, for the first time in northwestern France near Calais (Toussaint 2016).
Smyrnium olusastrum used to be a common kitchen herb in medieval Europe (incl. the Netherlands) (Brinkkemper 2015). It may have become more popular again in recent times as a ‘forgotten vegetable’.
A very valuable account about the species’ biology and ecology in the British Isles is presented by Randall (2003).
Anonymous (1996) Plant profile. Alexanders. Smyrnium olusatrum. Flora Facts and Fables 5: 10-12.
Brinkkemper O. (2015) Smyrnium olusatrum L. (Alexanders): an ancient kitchen herb from late medieval Rotterdam (the Netherlands). Vegetation History and Archaeobotany 24(1): 249-252. [available online at: https://www.researchgate.net/publication/263504089_Smyrnium_olusatrum_L_...
Llewellyn-Jones J. (1980) History of a plant, 7. Alexanders-Smyrnium olusatrum L. Bull. Basildon Nat. Hist. Soc. 62: 17.
Randall R.E. (2003) Biological Flora of the British Isles: Smyrnium olusatrum L. J. Ecol. 91(2): 325-340. [available online at: http://onlinelibrary.wiley.com/doi/10.1046/j.1365-2745.2003.00761.x/full...
Terrisse A. (1990) Note historico-nomenclaturale sur le maceron (Smyrnium olusatrum L.). Bull. Soc. Bot. Centre-Ouest, n.s. 21: 71-74.
Toussaint B. (2016) Découvertes & curiosités 2016. Smyrnium olusastrum. Le Jouet du Vent 29: 3.
Van der Meijden R. (2005) Heukels’ Flora van Nederland (23e druk). Wolters-Noordhoff, Groningen: 685 p.