Elaeagnus pungens Thunb. (Japan) – A very rare but increasing escape from cultivation. A single shrub was discovered in 2012 in spontaneous woodland on rough ground at the KULAK-university near Kortrijk. In 2013 seen on several occasions in the same area and in the same type of habitats. Probably overlooked elsewhere, especially in climatologically favourable areas.
Elaeagnus pungens is a reputed invasive environmental weed outside its native distribution range, for instance in North America and Australia (numerous references on www; see also Randall 2007). In western Europe, Elaeagnus pungens, seems to be much scarcer in the wild (the usual evergreen species of Elaeagnus in our gardens being E. xsubmacrophylla). It is claimed as locally naturalized in the Netherlands (Christenhusz & van Uffelen 2001). In the British Isles it is a mere relic of cultivation (Clement & Foster 1994). However, in parts of southern Europe and southernmost Central Europe Elaeagnus pungens is increasingly naturalizing. It is one of the characteristic species of the laurophyllisation process, the naturalization of broad-leaved evergreen exotic species as a result of climate change (e.g. Walther 2000, Klötzli 2003, Zäch 2005).
Selected literature:
Christenhusz M.J.M. & van Uffelen G.A. (2001) Verwilderde Japanse planten in Nederland, ingevoerd door von Siebold. Gorteria 27: 97-108.
Clement E.J. & Foster M.C. (1994) Alien plants of the British Isles. BSBI, London: XVIII + 590 p.
Klötzli F. (2003) Zur Einnistung von exotischen Wärmezeigern in Südtessiner (insubrischen) Wäldern. Bull. Soc. Frib. Sc. Nat. 92: 47-60. [available online at: http://www.unifr.ch/sfsn/pdf/vol%2092]
Randall R.P. (2007) The introduced flora of Australia and its weed status. CRC for Australian Weed Management. Available online at: http://www.weeds.org.au/docs/intro_flora_australia.pdf.
Walther G.-R. (2000) Laurophyllisation in Switzerland. PhD thesis. Available online at: http://e-collection.library.ethz.ch/view/eth:23429.
Zäch R. (2005) Ökologie und Ausbreitung von Neophyten auf dem Monte Caslano im Südtessin. Diplomarbeit Geobotanisches Institut ETH Zürich. Available online at: http://e-collection.library.ethz.ch/eserv/eth:28314/eth-28314-01.pdf.