Checklist » Dryopteridaceae » Polystichum imbricans ssp. imbricans
Polystichum imbricans (D.C. Eaton) D.H. Wagner ssp. imbricans[FNA2, HC2]
imbricate fern, narrow-leaved sword fern

Publication: Pteridologia. 1: 50. 1979.

Origin: Native

Herbarium search: CPNWH

Notes: FNA2: "Polystichum imbricans subsp. imbricans grows in the Coast Ranges and the Sierra-Cascade axis. It is isolated in the Wallowa Mountains of eastern Oregon.

Sun forms of Polystichum munitum are often mistaken for P . imbricans ; characteristics of the distal petiolar scales and indusial margins are more reliable than gross morphologic features for distinguishing them. Polystichum imbricans has narrow distal petiolar scales that fall off early; P . munitum has wide distal petiolar scales (the largest more than 1 mm wide) that are persistent. Polystichum imbricans hybridizes readily with P . munitum , the hybrids usually being sterile but in some places forming hybrid swarms because of partial fertility of the hybrids (D. H. Wagner 1979). The hybrids with P . californicum are discussed under that species."

Last updated 9/28/2023 by David Giblin.

Synonyms & Misapplied Names:
Polystichum munitum (Kaulf.) C. Presl ssp. nudatum (D.C. Eaton) Ewan
Polystichum munitum (Kaulf.) C. Presl var. imbricans (D.C. Eaton) Maxon[HC, Peck]