1. Eurybia divaricata (L.) Nesom (syn.: Aster divaricatus L., A. corymbosus Ait.) (N-Am.) – A very rare escape from cultivation or garden throw-out. First discovered in 1946 in young birchwood in the surroundings of a coalmine heap in Goutroux (along with Achillea nobilis) (Duvigneaud 1970, Lebeau 1973). Locally naturalised for several decades (last confirmed in 1984) but possibly gone now. Small but more or less naturalised populations have been recorded in a woody road verge in Belsele (Sint-Niklaas) in 2002 and in a clearing in woodland in Zedelgem (Merkenveld) in 2011. Occasionally seen elsewhere (Roeselare,…) but probably always ephemeral.
References
Duvigneaud J. (1970) Présence d’Aster divaricatus L. en Belgique. Nat. Mosana 23: 35-36.
Lebeau J. (1973) Excursion du 18 août 1973 dans la région au nord-ouest de Charleroi à Souvret et Goutroux. Nat. Mosana 26(4): 132-135.
Pyšek A. & Vobořil Z. (2002): Vzácný druh hvězdnice (Aster divaricatus L.) v Tachově a jeho blízkém okolí. Zpr. Čes. Bot. Společ. 37(1): 107-110.