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D. affinis resources
Descriptive
brief accountbrief account
good close-ups with diagnostic dark spotsgood close-ups with diagnostic dark spots
Monograph
Hoshizaki and WilsonHoshizaki and Wilson
Photo
good images, ssp borrerigood images, ssp borreri
lower frondlower frond
Photo index
Bioimages: many good images, ssp borreriBioimages: many good images, ssp borreri
Taxonomy
<b>Affinis Watch</b>: 10 naturally-occuring formsAffinis Watch: 10 naturally-occuring forms

All Ferns
  Dryopteridaceae
   Dryopteris
     aemula  affinis
     amurensis  arguta
     bissetiana  campyloptera
     carthusiana  caucasica
     celsa  championii
     clintoniana  crassirhizoma
     cristata  cycadina
     cystolepidota  decipiens
     dilatata  erythrosora
     expansa  filix-mas
     formosana  fragrans
     fuscipes  goldiana
     hondoensis  intermedia
     kuratae  lacera
     lepidopoda  ludoviciana
     marginalis  mindshelkensis
     oreades  pacifica
     polylepis  pseudo-filix-mas
     purpurella  remota
     sacrosancta  saxifraga
     sieboldii  stewartii
     sublacera  tokyoensis
     uniformis  varia
     wallichiana

 Other Genera
    Adiantum  Arachniodes
    Aspidotis  Asplenium
    Astrolepis  Athyrium
    Blechnum  Cheilanthes
    Cryptogramma  Cyrtomium
    Cystopteris  Dennstaedtia
    Deparia  Diplazium
    Gymnocarpium  Lygodium
    Matteuccia  Onoclea
    Oreopteris  Osmunda
    Pellaea  Phegopteris
    Pleopeltis  Polypodium
    Polystichum  Pteridium
    Pteris  Pyrrosia
    Thelypteris  Woodsia
    Woodwardia
 
Dryopteris affinis (Lowe) Fraser-Jenkins

Scaly male fern

Etymology affinis, Latin: neighboring or akin to, perhaps referring to similarity to the male fern, D. filix-mas
Description Rhizome: erect, stout.
Frond: 100 cm high by 20 cm wide, deciduous early in colder areas, monomorphic, blade/stipe ratio: 4:1.
Stipe: grooved, golden-brown, dense, conspicuous scales with a dark base, petering out only after the fourth or fifth set of pinnae, vascular bundles: 3-7 in a c-shaped pattern.
Blade: 2-pinnate, lanceolate, usually tapering towards the base, leathery, lustrous, yellow-green, scales continue on underside of costa.
Pinnae: 30 to 35 pair, subopposite on rachis, base with a dark blotch (diagnostic fresh, missing when dried); pinnules oblong, usually truncated at the apex; costae grooved above; segments oblong; margins somewhat crenate; veins free, forked.
Sori: round, in 1 row between midrib and margin, indusium: doughnut-shaped, convex, steel-gray when young, aging to brown, at a sinus, sporangia: black, maturity: mid to late summer.
Culture Habitat: woods and shady places, open areas among rocks. Distribution: Europe to Caspian to North Africa. Hardy to -30°C, USDA Zone 4.
Distinctive Characteristics dark blotch on the costa at its junction with rachis
Synonyms
Dryopteris pseudomas (Wollaston) Holub et Pouzar
Dryopteris borreri Newm.
Dryopteris abbreviata Newm.
Lastrea abbreviata Woll.
Nephrodium abbreviatum Lowe
Polystichum abbreviatum Lam. & DC.
Dryopteris affinis
Dryopteris affinis. top left: pinna base and sori; stipe scales.  Illustration from Scandinavian Ferns by Benjamin Ĝllgaard and Kirsten Tind, Rhodos, 1993.
Notes
Compare to D. filix-mas and D. oreades. C.N. Page writes "The more generally shining frond which is more yellow green on flushing, the denser, generally more golden-brown scales ..., the stiffer, more leathery frond texture, the narrow pinnae with usually more truncated segments, the laxer crozier when flushing, and the dark patch to the base of each pinna distinguish most specimens of all subspecies of D. affinis from both D. filix-mas and D. oreades, the only other species with which they are likely to be confused."
Progeny All D. affinis are apogamous, i.e., the offspring are identical to the parent plant, hence, no variation except for the occasional mutations that have given rise to all the cultivars.
ssp. borreri frond/stipe ratio 2:1, i.e., a longer stipe than ssp affinis, stipe scales straw to pale gray-brown rather than golden-brown. The dark blotch at the junction of rachis and costa is mentioned as true for the species, but shows up in none of the subspecies images above.
ssp. cambrensis blade longer, narrower, lower pinnae gradually shorter, the lowest half the middle, pinnules of uneven length, often twisted, often with margins folded down, scales reddish-golden, glossy, twisted on the upper stipe. This taxon may include parentage from D. oreades or D. caucasica or both.
Dryopteris affinis
Dryopteris affinis.  Illustration from The Cultivated Species of the Fern Genus Dryopteris in the United States, Barbara Joe Hoshizaki and Kenneth A. Wilson, American Fern Journal, 89, 1, (1999), with permission.
Dryopteris affinis
Dryopteris affinis. Frond.  Illustration from Scandinavian Ferns by Benjamin Ĝllgaard and Kirsten Tind, Rhodos, 1993.
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