Dryopteris marginalis

Marginal Shield Fern

Marginal Shield  Fern, Photo courtesy Wisconsin State Herbarium and Emmet J. Judziewicz
Marginal Shield Fern
Photo courtesy Wisconsin State Herbarium
and Emmet J. Judziewicz

Flora, fauna, earth, and sky...
The natural history of the northwoods


Name:

  • Dryopteris, from the Greek, drus (drys), "oak" and pteris (pteris), "fern", "fern of the oak wood"
  • marginalis, from the Latin marginatus, "to border, enclose with a margin".
  • Common name from the location of the spore bearing sori along leaf edge.
  • Other common names include Evergreen Wood Fern, Leather Wood Fern, Marginal Wood Fern, Marginal-fruited Shield Fern, Dryoptère à Sores Marginaux (Qué), Varen (NL)

Taxonomy:

  • Kingdom Plantae, the Plants
    • Division Polypodiophyta, the True Ferns
      • Class Filicopsida
        • Order Polypodiales
          • Family Dryopteridaceae, the Wood Ferns
            • Genus Dryopteris, the Wood Ferns
  • Taxonomic Serial Number: 17541
  • Also known as Aspidium marginale, Polypodium marginale, Thelypteris marginalis

Description:

  • A large, leathery woodland fern with fronds borne in crown-like cluster.
  • Fronds monomorphic, evergreen, 5"-8" wide and 12"-24" long; lanceolate to ovate-oblong.
    • Petiole (leaf stalk) stout and brittle with grooved face; reddish brown at swollen base, becoming brownish green above; covered with golden brown scales.
    • Blade ovate-lanceolate, blue green above with light green undersides; texture leathery.
    • Rachis (axis) pale, grooved in front, somewhat scaly.
    • Pinnae (primary leaflets) lanceolate and more-or-less in plane of blade; lowest pair slightly reduced in size.
    • Pinnules (secondary leaflets) lowest pair longer than adjacent pinnules; basal basiscopic pinnule (lowest downward pointing subleaflet on lowest pinnae) longer than basal acroscopic pinnule (lowest upward pointing subleaflet on lowest pinnae); pinnule edges shallowly crinkled to nearly smooth.
  • Rootstalk stout, erect or ascending, ungrooved, brown-green above, darker near base, 6"-12" long and 1"-2" thick, covered with brown, closely overlapping leaf bases and soft, brown, chaffy scales.
    • Roots many, shallowly spreading, and often exposed.
    • Fiddleheads densely covered with golden brown hairs.
  • Sori located on the pinnae edges or margins, hence the species name.
    • Indusia kidney shaped, prominent.

Identification:

  • Identifiable as a Wood Fern by its larger size, thrice-cut fronds, and woodland habitat.
  • Distinguished from more typical Wood Ferns (Dryopteris sp.) by its leathery texture and its characteristic sori, neatly arranged along the margins of the leaflets.
  • Field Marks
    • leathery blades
    • sori borne near margins

Distribution:

  • Ontario to Newfoundland and Greenland, south to Mississippi, Alabama, Georgia, and South Carolina.
  • Classified as Threatened in Minnesota.
  • While not collected from our area, it is known from similar habitat in northwestern Wisconsin and on Isle Royale, and should not be completely unexpected in northeastern Minnesota.

Habitat:

  • Rich woodlands, woodland edges, ravines, rocky slopes or outcroppings, stream banks and roadbanks.

Fire:

Associates:

History:

Uses:

Reproduction:

  • By spore and vegetatively by rhizome.

Propagation:

  • By division of small crowns near main rosette.

Cultivation:

  • Hardy to USDA Zone 3 (average minimum annual temperature -40ºF)
  • Cultural Requirements
    • Shade to part shade
    • Moist, organic soil
    • Protect from sun and drying winds
  • Size 18"-24"H x 12"-18"W
  • Available by mail order from specialty suppliers or at local nurseries
  • Good for shaded rock or woodland garden, native gardens. Spreads slowly.

Links:

Comments:

Valley Internet Company
Return to Home Page
Send Feedback to Webmaster

Last Updated on 26 February, 2004