Cyrtomium fortunei

Cyrtomium fortunei J. Smith (syn.: Polystichum fortunei Nakai) (temp. Asia) – A rare escape from cultivation but increasingly found since 2001, predominantly in urban areas, especially in some larger cities in Flanders (Antwerpen, Gent). Plants are usually found on old walls (often quays), basement walls, in sewers, against rain pipes,… In 2011 it was furthermore observed, apparently for the first time, terrestrial in woodland in Moen (Orveytbos), on the verge of the canal Kortrijk-Bossuit. Cyrtomium fortunei appears to be very persistent and hardy but is not yet really naturalised so far. However, in 2007 a remarkable concentration of plants was found on several basement walls in Deurne-Noord (Antwerpen).

Plants with less and wider pinnae have been ascribed with some doubt to Cyrtomium cf. macrophyllum (Makino) Tagawa (Edgington 2005). At least the Belgian plants revealed to be juvenile plants of Cyrtomium fortunei and this possibly also holds true for very similar plants from London (Edgington 2005, 2006).

Herbarium specimen

Cyrtomium fortunei leaflet

Cyrtomium fortunei, Antwerpen, old wall, 2005. Erik Molenaar
Cyrtomium fortunei, Antwerpen, old wall, 2005. Erik Molenaar  


Selected literature

Bonali F. (1996) Segnalazione di Cyrtomium fortunei J. Sm. una felce naturalizzata nuova per il Cremonese. Pianura 8: 137-140.

Denters T. & Verloove F. (2008) Smalle ijzervaren, Cyrtomium fortunei J. Sm. nieuw voor Nederland. Gorteria 33(2): 33-40.

Edgington J.A. (2005) Exotic ferns on London walls. BSBI News 100: 42-44.

Edgington J.A. (2006) Wall-to-wall ferns. BSBI News 102: 20-21.

Fontaine P. & Saintenoy-Simon J. (2007) Cyrtomium fortunei au domaine Solvay. Adoxa 57: 27-28.

Gholipour A. & Greuter W. (2010) A new genus for the fern flora of Iran: Cyrtomium. Fern Gaz. 18(8): 336-341. [available online at:]

Hulsey T.A. & Meier A.J. (2011) A record of Cyrtomium fortunei J. Sm. in Kentucky with comments on the spread of this exotic species in the Southeastern United States. Castanea 76(4): 427-428.

Page C.N. (2005) A second species of the fern genus Cyrtomium naturally established in West Cornwall. BSBI News 98: 39-41.

Pignatti E., Pignatti S. & Poldini L. (1983) Cyrtomium fortunei J. Sm., neu für die italienischen Ostalpen. Botanica Helvetica 93: 313-316.

Röhner G. (2012) Angesalbte und adventive Farnpflanzen an der Bergstrasse. Hess. Florist. Br. 60(2): 20-24.

Scratchpads developed and conceived by (alphabetical): Ed Baker, Katherine Bouton Alice Heaton Dimitris Koureas, Laurence Livermore, Dave Roberts, Simon Rycroft, Ben Scott, Vince Smith