Polystichum munitum

Polystichum munitum (Kaulfuss) C. Presl (N Am.) - An exceptional escape from cultivation. A single individual was discovered in young spontaneous woodland in Kontich (Vuile Plas) in 2019.

This species looks similar to native P. lonchitis. It usually is a coarser species with longer fronds. Most characteristic, however, is that basal pinnae are not markedly shorter than the longest.

Polystichum munitum is widely cultivated as an ornamental. It is sometimes locally naturalized in Europe, for instance in a few places in the British Isles and Ireland (Leslie 1981, Clement & Foster 1994, Stace 2010). A hybrid with native P. setiferum, P. x lesliei Rumsey & Acock, has been recorded in the localities where both species grow together in Britain (Acock & al. 2001).

Selected literature

Acock P.J., Rumsey F.J., Murphey R. & Bennallick I. (2001) Polystichum x lesliei (P. munitum x P. setiferum) (Dryopteridaceae: Pteridophyta) described and a second site reported. Fern Gaz. 16(5): 245-251. [available online at: https://www.ebps.org.uk/wp-content/uploads/2014/05/FGV16P5M5.pdf]

Chagneau D. (2003) Signalement de Polystichum munitum en Loire-Atlantique. Erica 18: 27-28.

Clement E.J. & Foster M.C. (1994) Alien plants of the British Isles. BSBI, London: XVIII + 590 p.

Leslie A.C. (1981) Polystichum munitum Presl - a new British alien. BSBI News 28: 24. [available online at: http://archive.bsbi.org.uk/BSBINews28.pdf]

Stace C. (2010) New flora of the British Isles, 3th ed.: XXXII + 1232 p. Cambridge University Press.

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