Adiantum pedatum

Linnaeus

Sp. Pl. 2: 1095. 1753

Common names: Northern maidenhair adiante du Canada
Synonyms: Adiantum pedatum forma billingsae Kittredge Adiantum pedatum forma laciniatum (Hopkins) Weatherby
Treatment appears in FNA Volume 2.
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Illustrator: John Myers
Stems short-creeping; scales bronzy deep yellow, concolored, margins entire. Leaves lax-arching (rarely pendent), closely spaced, 40–75 cm. Petiole 1–2 mm diam., glabrous, occasionally glaucous. Blade fan-shaped, pseudopedate, 1-pinnate distally, 15–30 × 15–35 cm, glabrous; proximal pinnae 3–9-pinnate; rachis straight, glabrous, occasionally glaucous. Segment stalks 0.5–1.5(–1.7) mm, dark color entering into segment base. Ultimate segments oblong, ca. 3 times as long as broad; basiscopic margin straight; acroscopic margin lobed, lobes separated by narrow incisions 0–0.9(–1.1) mm wide; apex obtuse, divided into shallow, rounded lobes separated by shallow sinuses 0.1–2(–3.7) mm deep, margins of lobes crenulate or crenate-denticulate. Indusia transversely oblong, 1–3 mm, glabrous. Spores mostly 34–40 µm diam. 2n = 58.

Phenology: Sporulating summer–fall.
Habitat: Rich, deciduous woodlands, often on humus-covered talus slopes and moist lime soils
Elevation: 0–700 m

Distribution

V2 74-distribution-map.gif

N.B., N.S., Ont., Que., Ala., Ark., Conn., Del., D.C., Ga., Ill., Ind., Iowa, Kans., Ky., La., Maine, Md., Mass., Mich., Minn., Miss., Mo., Nebr., N.H., N.J., N.Y., N.C., Ohio, Okla., Pa., R.I., S.C., Tenn., Vt., Va., W.Va., Wis.

Discussion

Once considered a single species across its range in North America and eastern Asia, Adiantum pedatum is considered to be a complex of at least three vicariant species (A. pedatum and A. aleuticum occur in North America) and a derivative allopolyploid species (C. A. Paris 1991). Adiantum pedatum in the strict sense is restricted to deciduous woodlands in eastern North America.

References

None.

Lower Taxa

No lower taxa listed.