Euonymus alatus (Thunb.) Siebold (E-As.) – An exceptional escape from cultivation. A single young shrub was discovered in a ditch in Balen (Mol) in 2011. In 2014 also found on the verge of a former clay pit in Kortrijk.
Euonymus alatus, at least in its typical form (var. alatus), is a very distinctive species. Only two species of Euonymus have conspicuous corky wings: E. alatus and E. phellomanus Loes. Both are frequently cultivated in western Europe (De Koning & al. 2000, Roloff & Bärtels 2006) and are very similar in the non-flowering state. However, they are not even remotely related and are accommodated in different sections by Ma (2001), respectively sect. Melanocarya and sect. Euonymus. Euonymus alatus has nearly sessile leaves (leaf stalk at most 2 mm long) and capsules with four lobes that are free nearly to base; E. phellomanus, in turn, has distinctly petiolate leaves (leaf stalk up to 10 mm long) and a four-lobed capsule with lobes united for most of their length. The shrubs found in Kortrijk are characterized by the absence of corky wings. Such plants have been erroneously ascribed to var. apterus Loes. but this is a synonym of E. verrucosoides Loes., a fairly different species (e.g. Ma 2001). Such plants resemble E. europaeus a lot but are distinguished by leaves that are subsessile.
Despite being frequently cultivated as an ornamental shrub there are surprisingly few records of Euonymus alatus in the wild in western Europe (see for instance Wilmore 2000 for the British Isles). In parts of the United States it is a noxious environmental weed (numerous references on www).
De Koning J., Van den Broek J.W., Van de Laar H.J. & Fortgens G. (2000) Nederlandse dendrologie (13e druk). H. Veenman & zonen, Ede: 585 p.
Ma J. S. (2001) A Revision of Euonymus (Celastraceae). Thaiszia 11: 1-264.
Roloff A. & Bärtels A. (2006) Flora der Gehölze (2e Auflage). Ulmer, Stuttgart: 844 p.
Wilmore G.T.D. (2000) Alien plants of Yorkshire. Nats. Union, Bradford.