Practical ecological knowledge for the temperate reader.

Northern Maidenhair - Adiantum aleuticum

Thiaminase Basketry, Hair Wash Congestion, Fevers, Rheumatism



"Adiantum pedatum is a FERN growing to 0.5 m (1ft 8in) by 0.5 m (1ft 8in) at a slow rate.
It is hardy to zone (UK) 3. The seeds ripen from Aug to October.
Suitable for: light (sandy), medium (loamy) and heavy (clay) soils and prefers well-drained soil. Suitable pH: acid, neutral and basic (alkaline) soils. It can grow in semi-shade (light woodland). It prefers moist soil." [PFAF]

This species as listed subtaxa [E-flora]


General: "Deciduous perennial, palmately branched, from a stout, scaly rhizome, 15-75 cm tall." [IFBC-E-flora]
Leaves: "Broadly fan-shaped, 10-75 cm long; stalks reddish-brown to purplish-black; blades more or less palmately-pinnate, set at right angles to the stalks and more or less parallel to the ground, 10-40 cm long, 10-40 cm wide, rounded to kidney-shaped, forked at the bases into 2 recurved-spreading divisions which in turn bear 2-several shorter divisions, the larger divisions with 15-35, alternate, short-stalked" [IFBC-E-flora]
Notes: "Small plants with small fronds (5 to 15 cm across) and strongly overlapping ultimate segments were described as A. pedatum L. var. subpumilum Wagner. They clearly belong to this species, but no formal nomenclatural transfer has been done yet. This variety is rare on coastal bluffs from northern Vancouver Island south to the Olympic Peninsula, WA." [IFBC-E-flora]
Habitat / Range
"Moist forests, rocks, scree, cliffs, banks and waterfall spray zones in the lowland and montane zones; frequent throughout BC, mostly S of 55°N, infrequent in SC BC; amphiberingian, N to AK, E to SW AB and S to CO, AZ and CA; disjunct E to PQ and NF and S to PA, WV and MI; E Asia."[IFBC-E-flora]
"N. America - Alaska to Quebec and Nova Scotia, south to California and Georgia. E. Asia" [PFAF]


Thiaminase containing family: "Although we have found no reports of toxicity for this species, a number of ferns contain carcinogens so some caution is advisable[200]. Many ferns also contain thiaminase, an enzyme that robs the body of its vitamin B complex. In small quantities this enzyme will do no harm to people eating an adequate diet that is rich in vitamin B, though large quantities can cause severe health problems. The enzyme is destroyed by heat or thorough drying, so cooking the plant will remove the thiaminase[172]." [PFAF]

Other Uses

Medicinal Uses

"This plant was highly valued as a medicinal plant in the 19th century and merits scientific investigation[222]." [PFAF]

Adiantum pedatum; "The Cherokee of North America gathered dried fronds, powdered them, and then smoked the powder for heart problems (Hamel and Chiltoskey 1975). The complete plant was powdered and smoked to relieve asthma attacks."[UAPDS] "The blades, stem and root of this fern are all used in the treatment of female maladies. In syrup or infusion, the roots of this fern have been used by the white man in the treatment of chronic affections of the respiratory tract. It is also said to be of value for the relief of cough."[HuronSmith Menomini] "The Forest Potawatomi used an infusion of the root to cure caked breasts in the nursing mother. It is drunk as a tea. Among the whites,227 the entire plant has been used for its pectoral, mucilaginous, expectorant, refrigerant and tonic properties. Another authority228 says that the herb has been used for its refrigerant, expectorant, tonic and sub-astringent properties. It has been used as a decoction in febrile diseases, helps coughs, catarrh, hoarseness, influenza, asthma and pleurisy."[HuronSmith Zuni]

Adiantum pedatum
  • "PH2 entries apply to European maidenhair. Grieve’s A Modern Herbal says A. pedatum is used like A. capillus-veneris “in similar ways and more highly valued by many” (GMH)."
  • "Activities (Northern Maidenhair) —Antirheumatic (f; HHB); Demulcent (f; PH2); Diuretic (f; DEM; WO3); Emetic (f; DEM); Expectorant (f; HHB; PH2); Pectoral (f; DEP; PH2); Propecic (f; PH2)."
  • Select Indications (Northern Maidenhair) — Cough (f; GMH; PH2); Rheumatism (f; DEM; HHB); Water Retention (f; DEM; WO3)."
  • Dosages (Northern Maidenhair) — 1.5 g herb/cup tea (PH2)."
  • Hazards "Not for use during pregnancy (PH2)." [HMH Duke]



"Easily grown in a cool moist shady position[1, 187]. Requires an abundance of moisture in the air and soil[1]. Prefers an alkaline soil[200]. Requires an acid soil according to another report. A very ornamental plant[1], it does not always succeed outdoors in Britain[1]. It probably prefers to be covered in snow overwinter - could a mulch help[1]? This species is often divided into three separate species by botanists - the type species is found in eastern N. America, A. aleuticum is found in western N. America and a third species is found in eastern Asia[270]. Members of this genus are rarely if ever troubled by browsing deer[233]. Plants have a slowly-increasing rootstock[233]." [PFAF]


"Spores - best sown as soon as ripe on the surface of a humus-rich sterilized soil. Keep the compost moist, preferably by putting a plastic bag over the pot. Pot on small clumps of plantlets as soon as they are large enough to handle and keep them humid until they are well established. Do not plant outside until the ferns are at least 2 years old and then only in a very well sheltered position. Division in spring or autumn." [PFAF]


  1. [E-flora] - Adiantum aleuticum,, Accessed April 8, 2015
  2. [PFAF]Adiantum pedatum - Northern Maidenhair,American Maidenhair Fern,, Accessed April 8, 2015

Adiantum Sp.

"Plant in soil or rock crevices; rhizome short-creeping, scales variously colored. Leaf: < ± 1 m; stipe cylindric, generally dark red-brown to ± black, shiny, ± scaly at base; blade 2–3-pinnate or ± palmate-pinnate (1st division ± palmate, subsequent ones pinnate), pinnae stalked, fan-shaped or oblong, generally lobed, toothed, or both; axes, blades lacking colored exudate. Sporangia: borne along veins on and covered by highly modified, recurved part of segment margin, appearing to run together at maturity; false indusia ± semicircular to linear; spores generally smooth, tan.
± 200 species: tropics, temperate. (Greek: unwettable) Widely cultivated." [Jepson]

Local Species;

  1. Adiantum aleuticum - northern maiden-hair

Other non-local Species in B.C.

  1. Adiantum capillus-veneris - southern maiden-hair (common maidenhair) [Rare in Eastern B.C.]


Adiantum sp

Emmenagogue Duke,1972; Expectorant Duke,1972 [Duke]

Maidenhair - Adiantum capillus-veneris

Adiantum capillus-veneris "The only convincing evidence that Adiantum capillus-veneris has truly been a folk herb in Britain or Ireland comes from the latter’s remote Aran Islands, where it is sufficiently frequent in the wild for its dried fronds to have been used to make a tea.33" [MPFT]


Page last modified on Monday, January 10, 2022 6:41 AM