Aesculus hippocastanum
Aesculus hippocastanum L. (SE Eur.) – A rather frequent and much increasing escape from cultivation. The escape of this species in Belgium is poorly documented. According to Van den Bremt & al. (1980) it was already naturalized in the Osbroek nature reserve in Aalst at the end of the 1970’s. This apparently was the first documented naturalization event in Belgium although previous attempts may have been merely neglected. Nonetheless, the naturalization and spread of Aesculus hippocastanum certainly is a relatively recent phenomenon (Verloove 2006). While at first most records were from parks and other urban habitats – always in close proximity to planted individuals – it is now increasingly found in more remote and natural habitats. For instance, it is locally naturalizing in riparian woodland along river Scheldt (Verloove 2011). Also in Wallonia A. hippocastanum has been reported from relatively remote areas; it is believed to be dispersed – among others – by birds, incl. spotted nutcracker (Kerger & al. 1994).
On a global scale and despite being widely cultivated outside its native distribution range, Aesculus hippocastanum is considered ‘vulnerable’ according to IUCN standards. Many populations have been severely damaged by a leafminer moth (Cameraria ohridella), both across its native and introduced range (http://www.iucnredlist.org/details/202914/0).
Selected literature:
Kerger M.-T., Parent G.H. & Thoen D. (1994) Matériaux pour la troisième édition de l’Atlas de la flore belge et luxembourgeoise (observations de 1982 à 1991). Adoxa 2: 13-20.
Van den Bremt P. Fobert L. & Lebcq J. (1980) Resultaten van een floristisch onderzoek in het Osbroekgebied in Aalst-Erembodegem: 1977-1979. Dumortiera 17: 1-13.
Verloove F. (2006) Aesculus hippocastanum. In: Van Landuyt W., Hoste I., Vanhecke L., Van den Bremt P., Vercruysse W. & De Beer D., Atlas van de flora van Vlaanderen en het Brussels gewest. Instituut voor Natuur- en Bosonderzoek, Nationale Plantentuin van België en Flo.Wer: 109.
Verloove F. (2011) Fraxinus pennsylvanica, Pterocarya fraxinifolia en andere opmerkelijke uitheemse rivierbegeleiders in België en Noordwest-Frankrijk. Dumortiera 99: 1-10. [available online at: http://www.plantentuinmeise.be/DUMORTIERA/DUM_99/Dum%2099_1-10_Fraxinus%...