Smilax aspera L. (syn.: S. maculata Roxb., S. mauritanica Poiret, S. nigra Willd.) (Medit., SW-As.)
An exceptional escape from cultivation. Discovered in 2008 in a cemetery in Roeselare, possibly bird-sown (a single specimen in a crack on a gravestone). Confirmed in 2009 but apparently killed by frostbite in 2010. Smilax aspera was furthermore recorded in 2008 as a container weed in nurseries (with imported olive trees; see Hoste & al. 2009).
The origin of the plant from Roeselare is obscure. Smilax aspera is only rarely cultivated as an ornamental and obviously not fully hardy. However, an introduction by birds seems most feasible.
Bay T. (2016) Smilax aspera. Kletternder Bodensanierer. Gartenpraxis 10-2016: 28-29.
Hoste I., Verloove F., Nagels C., Andriessen L. & Lambinon J. (2009) De adventievenflora van in België ingevoerde mediterrane containerplanten. Dumortiera 97: 1-16.