shield ferns

genus Polystichum

Member of shieldfern family (family Dryopteridaceae)
eupolypods i (suborder Polypodiineae)
leptosporangiate ferns (subclass Polypodiidae)
ferns (class Polypodiopsida)

Except for historical records that I'm ignoring, there are no other wild species of this genus in the bay area.

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narrowleaf sword fern
Polystichum imbricans

• frond 1-pinnate
• stipe base scales lanceolate, ± 2–3 mm wide
• those above proximal pinnae generally < 1 mm wide, falling early
• rare

california shield fern
Polystichum californicum

• frond generally 2-pinnate, but pinnules range from 0% to 100% divided
• pinnules gradually tapered to attachment < 3 mm wide [or not fully divided]
• common

dudley’s shield fern
Polystichum dudleyi

• frond 2-pinnate
• pinnules abruptly narrowed to attachment < 0.5 mm wide
• common

Toxicity of christmas dagger fern (Polystichum spp.):
0 – Non-toxic.

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1 observed taxon / 3 unobserved taxons / 1 key

Chris’s observations: 10 (8 are research grade)

Locations:

• Russian Ridge OSP: 2
• Sanborn CP: 2
• El Corte de Madera OSP
• Huckleberry Botanic RP
• Lake Chabot RP
• Monte Bello OSP
• Pescadero Creek CP
• Purisima Creek Redwoods OSP

Months:

• Dec.: 1
• Jan.: 1
• Feb.: 1
• Mar.: 1
• Apr.: 1
• May: 1
• Jun.: 1
• Jul.: 1
• Aug.: 2

For more details, use advanced search.

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Taxon info: iNaturalist – Calflora – Jepson eFlora – FNA

Bay Area species: iNaturalist – Calflora