Catalpa bignonioides Walter (U.S.A.) – A rather rare but much increasing escape from cultivation, usually ephemeral. First reported as an escape from Brussel around 1999 (Geerinck 1999). Subsequently seen in several different and widely scattered locations (see Verloove 2002) but nearly always in urban habitats: cracks in pavement, foot of walls, abandoned railway yards or industrial sites, near parks, etc. Sometimes also observed on river banks. A subspontaneous specimen in Profondeville flowers since 2006 (Saintenoy-Simon 2008). A local naturalisation in a near future seems very likely.
Records of the two other species in this account might erroneously pass as Catalpa bignonioides.
Selected literature
Adolphi K. (1995) Neophytische Kultur- und Anbaupflanzen als Kulturflüchtlinge des Rheinlandes. Nardus 2: 272 p.
Geerinck D. (1999) De la découverte de Catalpa bignonioides Walter à l’état subspontané en région de Bruxelles-Capitale. Les Naturalistes Belges 80: 441-442.
Kirkbride J.H. & Olsen R.T. (2011) Identity of Catalpa tibetica (Bignoniaceae). J. Bot. Res. Inst. Texas 5(2): 625-631. [available online at : http://www.brit.org/sites/alienplantsbelgium.bedefault/files/public/BRIT%20Press/JBRIT5%282%29/625-631_KirkbrideOlsen_Catalpa_JBRIT5%282%29625-631_20c.pdf]
Saintenoy-Simon J. (ed.) (2008) Trouvailles floristiques récentes (2006-2007. Adoxa 59: 17-51.
Verloove F. (2002) Ingeburgerde plantensoorten in Vlaanderen. Mededeling van het Instituut voor Natuurbehoud n° 20: 227 p.