Species
+

Adiantum pedatum L.

Northern Maidenhair fern (EN), Northern maidenhair fern, five-finger fern, maidenfern

Climate known 53 photographs Fern or moss
Add one to my plants Sow seed

Every figure on this page is derived from public data by a stated rule and says its source; nothing here is written by a person or a model, except the Wikipedia passage, which is quoted and marked as such. How it is made.

Summary

Adiantum pedatum, the northern maidenhair fern, is a species of fern in the family Pteridaceae, native to moist forests in eastern North America. Like other ferns in the genus, the name maidenhair refers to the slender, shining black stipes. Taxonomy classification disputes occur due to the distribution of A. Pedatum in both North America and East Asia.

Text from Wikipedia, “Adiantum pedatum”, CC BY-SA 4.0, quoted as written. Kept separate from everything derived here.

About the genus · Adiantum

Adiantum, the maidenhair fern, is a genus of about 250 species of ferns in the subfamily Vittarioideae of the family Pteridaceae, though some researchers place it in its own family, Adiantaceae. The genus name comes from Greek, meaning "unwetted", referring to the fronds' ability to shed water without becoming wet.

Text from Wikipedia, “Adiantum”, CC BY-SA 4.0, quoted as written.

Family
Pteridaceae
Described by
L.
Native to
Amur, Khabarovsk, Primorye +53
Wild records
1643 in range· 447 open

At a glance

Warmest month
27°C
Jul, mean day; nights 18 °C (CHELSA)
Rain
1132mm/yr
12 wet months · peak Jul 113 mm (CHELSA)
Light
10–39DLI
mol/m²/day, winter to summer, open sky (CHELSA shortwave)
In short condensed by rule from the cultivation cards · not written by a person
Grouped as a fern or moss by the genus Adiantum, which is reliably one kind of plant (archetype table). Rain rule: no season, 70% of the rain takes 8 months (April to November in the northern hemisphere). Habitat rain 1132 mm a year, wettest July at 113 mm, driest February at 70 mm (habitat calendar, northern hemisphere). Open sky over the habitat: 10 to 39 mol/m²/day. Cold floor 5 °C (archetype minimum for a fern or moss, above the -22.7 °C habitat night).
Each sentence is one card's own one-line form, written by the same rule as the card (Its year, Rain, Light, Temperature); the note cannot say what a card does not. Months are given for the northern hemisphere (set your site in Settings to change this), and the habitat's own alongside. The cards · the figures.

Also known as Adiantum americanum Nieuwl.; Adiantum grandifolium Ching; Adiantum pedatum f. billingsae Kittr.; Adiantum pedatum f. billingsii Kittr.; Adiantum pedatum f. laciniatum (Hopkins) Weath. and 12 more.

Cultivation

Grouped as a fern or moss by the genus Adiantum, which is reliably one kind of plant (archetype table). The table supplies one figure for this group, a conventional minimum for the cold floor, and no prose.

Its year Rain rule: no season, 70% of the rain takes 8 months (April to November in the northern hemisphere).

This species’ habitat figures, and what two fixed rules read from them.

The rain rule reads no season: 70% of the year's rain (813 mm of 1132 mm) takes 8 months, April to November. Mean temperature moves 26.6 °C between the warmest and coldest month. Months are the habitat's, northern hemisphere; shifted six months for a southern-hemisphere collection: October to May.

Read from the median year of CHELSA monthly rainfall and mean temperature across the envelope cells: the rain rule takes the smallest set of months carrying 70% of the rain and calls it winter when its mean is more than half a degree below the year's, summer when more than that above, and neither in between; the temperature rule, used only under 120 mm, names the cooler six months when they are at least a degree cooler than the other six. Months are shifted for the other hemisphere only where the temperature curve gives a season to reverse. A reading of the curves, not an observation of the plant.

Rain Habitat rain 1132 mm a year, wettest July at 113 mm, driest February at 70 mm (habitat calendar, northern hemisphere).

This species’ habitat figures, with their source.

1132 mm a year at the habitat, 813 mm of it April to November. Wettest month July at 113 mm, driest February at 70 mm. Across the envelope cells the year's total runs 855 mm to 1417 mm (10th to 90th percentile of each cell's own year) (median year across the envelope cells, CHELSA; habitat calendar, northern hemisphere).

CHELSA monthly precipitation, median year across the envelope cells. The rain that falls where the species is recorded; nothing about how the plant takes water.

Light Open sky over the habitat: 10 to 39 mol/m²/day.

This species’ habitat figures, with their source.

Open sky over the habitat: 10 to 39 mol/m²/day across the year (daily light integral, median year across the envelope cells, CHELSA; the lowest 10th-percentile month across the cells is 8, the highest 90th-percentile month 41).

CHELSA shortwave radiation at each envelope cell, a daily-mean flux taken to a daily total and converted at 2.07 mol of PAR per MJ. The sky over the habitat, measured; what reaches a plant under a rock, a shrub or a shade cloth is not.

Warmth and air Cold floor 5 °C (archetype minimum for a fern or moss, above the -22.7 °C habitat night).

This species’ habitat figures, with their source.

Temperature

Coldest: the 1st-percentile night over 44 years at the typical cell is -22.7 °C, the absolute minimum -38.9 °C, about 139 frost nights a year (NASA POWER daily minima). Warmest: the 99th-percentile day is 34.3 °C. Monthly means: coldest night -8.4 °C in January (across the envelope cells -14.6 °C to -1.4 °C), warmest day 27.1 °C in July (median year across the envelope cells, CHELSA). Cold floor: 5 °C. The habitat figure, the 1st-percentile night over 44 years at the typical cell (NASA POWER), is -22.7 °C; the archetype table's conventional minimum for a fern or moss (grouped by the genus Adiantum, which is reliably one kind of plant) is 5 °C, which is higher, and the floor rule takes the higher.

NASA POWER daily minima and maxima 1981–2024 at the typical cell, lapse-corrected to its elevation; CHELSA monthly means, median year across the envelope cells, CHELSA. The cold floor is the figure named in its sentence, and the archetype table's group minimum where that is higher. Not a measured survival limit for any plant in a pot.

Humidity

Relative humidity at the habitat: 56 to 61% across the year (monthly means, median year across the envelope cells, CHELSA). A figure about the air, saying nothing about how the plant takes water.

CHELSA relative humidity, median year across the envelope cells.

The figures the cards read from are in Climate below, and where they came from in Natural habitat.

Climate across the habitat

Habitat climate through the yearMean day from -1 °C in Jan to 27 °C in Jul; mean night from -8 °C in Jan to 18 °C in Jul. The cold quarter, Dec to Feb, is the three months around the coldest night. 1132 mm of rain a year, most in Jul. The bands show the 10th to 90th percentile across 1237 habitat cells. Over 44 years at the typical cell the absolute minimum was -38.9 °C and the 99th-percentile day 34.3 °C; neither is dated to a month. Beneath: daily light integral and relative humidity through the year, each on its own scale.-40°-20°20°40°frost34.3° 99th-percentile day (undated)-38.9° lowest night in 44 yrs (undated)°C · day and nightcold quarter0255075100125150mm rainDLI 10–39RH 56–61 %JanFebMarAprMayJunJulAugSepOctNovDec
day night rain 10th–90th percentile across 1237 habitat cells cold quarter: the three months around the coldest night extremes over 44 years at the typical cell, marked at the edge: undated DLI, mol/m²/dayRH %each on its own scale
Figures by month
JanFebMarAprMayJunJulAugSepOctNovDec
Day °C-1 / -5–82 / -3–107 / 2–1514 / 10–2020 / 17–2425 / 21–2927 / 24–3126 / 23–3022 / 19–2615 / 12–208 / 5–142 / -3–9
Night °C-8 / -15–-1-8 / -13–0-3 / -7–44 / 0–910 / 7–1415 / 12–1918 / 15–2117 / 15–2113 / 11–177 / 4–112 / -2–5-5 / -10–0
Rain mm77 / 25–11270 / 26–11485 / 45–12394 / 71–120106 / 84–138112 / 89–136113 / 89–141104 / 85–131101 / 84–12291 / 67–12192 / 52–12087 / 32–125
DLI13 / 10–1619 / 17–2126 / 25–2832 / 30–3537 / 35–3939 / 37–4138 / 37–4134 / 32–3627 / 24–3019 / 16–2413 / 10–1710 / 8–14
RH %61 / 57–6559 / 56–6357 / 55–5956 / 54–5757 / 55–5959 / 57–6159 / 57–6260 / 58–6260 / 57–6259 / 57–6160 / 57–6261 / 58–65

Each figure is the median across the 1237 grid cells holding the 1492 in-range records, with the 10th–90th percentile span across those cells after the slash where it differs. Extremes and elevation were read at the typical cell 963:1838 (41.825, -88.075). Over 44 years there: absolute minimum -38.9 °C, 1st-percentile night -22.7 °C, 99th-percentile day 34.3 °C. Normals: CHELSA V2.1 1981–2010 climatology, 0.05° cells (each the mean of ~36 1 km pixels). Envelope: median and 10th–90th percentile of each month across the 1237 distinct grid cells holding the 1492 in-range records; extremes and elevation at the typical cell 963:1838 (its coldest month's mean night nearest the median across cells); its position is the cell centre. Extremes: NASA POWER (MERRA-2) daily 1981–2024, cell 42.00_-88.125, lapse-corrected -10 m at 6.5 °C/km. Elevation: ETOPO 2022, 221 m (cell mean).

Natural habitat

Native range as published by WCVP; the marker is where the records are densest and decides nothing: the climate was read across every in-range record's cell, not at the marker.
Openly licensed records inside the range, framed on where they fall.
NativeAmur, Khabarovsk, Primorye, China South-Central, Manchuria, China North-Central, Qinghai, China Southeast, Tibet, Korea, Assam, East Himalaya, Nepal, Pakistan, West Himalaya, Myanmar, Alaska, New Brunswick, Nova Scotia, Ontario, Québec, Illinois, Iowa, Kansas, Minnesota, Missouri, Nebraska, Oklahoma, South Dakota, Wisconsin, Connecticut, Indiana, Maine, Massachusetts, Michigan, New Hampshire, New Jersey, New York, Ohio, Pennsylvania, Rhode I., Vermont, West Virginia, Alabama, Arkansas, Delaware, Georgia, Kentucky, Louisiana, Maryland, Mississippi, North Carolina, South Carolina, Tennessee, Virginia, District of Columbia
Kew's description“perennial or rhizomatous geophyte” · “temperate”· quoted from WCVP, RBG Kew (CC BY 4.0); not derived here
Map marker43.463, -72.441 · in the densest population, 834 records (51% of those in range)
Evidence usedThe map marker and the climate envelope rest on all 1643 georeferenced records inside the native range; the map shows only the 447 openly licensed ones, which alone would put the marker 193 km away. 275 records outside the range (gardens, roadsides, misidentifications) ignored. 151 in-range records are placed to worse than 10 km and stay on the map but off the climate.
The map markerthe map marker: the openly licensed record nearest the middle of the densest 1° population inside the densest 4° block of the 1643 in-range records; it decides nothing.

Photographs

Adiantum pedatumAdiantum pedatumAdiantum pedatumAdiantum pedatumAdiantum pedatumAdiantum pedatumAdiantum pedatumAdiantum pedatum

Photographs: no rights reserved · CC0 (8).

Photographs: iNaturalist and Wikimedia Commons did not answer when this page was built; what is shown came from the sources that did.

Papers naming this species

Works whose title or abstract names Adiantum pedatum, most cited first, from OpenAlex (CC0). A mention, not a cultivation source: nothing on this page is drawn from them.

Geomorphology and forest ecology of a mountain region in the central Appalachians
John T. Hack, John C. Goodlett (1960) · USGS professional paper
Pure polyploidy: Closing the gaps in autopolyploid research
Jonathan P. Spoelhof, Pamela S. Soltis, Pamela S. Soltis (2017) · Journal of Systematics and Evolution
The photosynthetic capacity in 35 ferns and fern allies: mesophyll CO 2 diffusion as a key trait
Tiina Tosens, Keisuke Nishida, Jorge Gago, Rafael E. Coopman (2015) · New Phytologist
Medicinal plants and other botanical products from the Brazilian Official Pharmacopoeia
Maria G.L. Brandão, Gustavo Pereira Cosenza, Raquel Assis Moreira, Roberto L. M. Monte-Mór (2006) · Revista Brasileira de Farmacognosia
The Eastern Asian and Eastern and Western North American Floristic Disjunction: Congruent Phylogenetic Patterns in Seven Diverse Genera
Qiu‐Yun Xiang, Pamela S. Soltis, Pamela S. Soltis (1998) · Molecular Phylogenetics and Evolution
The evolution, morphology, and development of fern leaves
Alejandra Vasco, Robbin C. Moran, Barbara A. Ambrose (2013) · Frontiers in Plant Science
Volcanic mercury and mutagenesis in land plants during the end-Triassic mass extinction
Sofie Lindström, Hamed Sanei, Bas van de Schootbrugge, Gunver Krarup Pedersen (2019) · Science Advances
Morphology of gymnosperms,
John M. Coulter, Charles J. Chamberlain, John M. Coulter (1917)
THE INDUCTION OF APOGAMY IN THE BRACKEN FERN
Dean P. Whittier, Taylor A. Steeves (1960) · Canadian Journal of Botany
Hybridization, Reticulation, and Species Concepts in the Ferns
David S. Barrington, Christopher H. Haufler, Charles R. Werth (1989) · American Fern Journal

Similar habitat climate the 6 species whose habitat climate is nearest this one's: mean day and night, month by month, and rain on a log scale, in calendar order, so a habitat with the same seasons six months out is far, not near. Nothing else counts: not range, not family.

Other Adiantum 1 in the reference

History & registers

Where this page came from built 2026-09-20 · dossier v2 · node
gbif.species answeredcarried from build of 2026-09-20 (offline re-derivation; the backbone was not asked)
gbif.synonyms answeredcarried from build of 2026-09-20 (offline re-derivation; the backbone was not asked)
gbif.vernacular answeredcarried from build of 2026-09-20 (offline re-derivation; the backbone was not asked)
wcvp.distribution answered
gbif.occurrences answeredGBIF occurrence download https://doi.org/10.15468/dl.3h4zam
climate answered
wikidata answeredcarried from build of 2026-09-20 (rederive); that build: carried from build of 2026-09-19 (rederive); that build: carried from build of 2026-09-19 (rederive)
wikipedia answeredcarried from build of 2026-09-20; this build: skipped
inat.taxon not askedcarried from build of 2026-09-20 (rederive)
inat.photos.wild answeredcarried from build of 2026-09-20; this build: skipped
inat.photos.cultivated nothing to reportcarried from build of 2026-09-20 (rederive); that build: carried from build of 2026-09-19 (rederive); that build: carried from build of 2026-09-19 (rederive)
commons not askedcarried from build of 2026-09-20 (rederive); that build: carried from build of 2026-09-19 (rederive); that build: carried from build of 2026-09-19 (rederive)
gbif.media answered
openalex answeredcarried from build of 2026-09-20; this build: skipped

Every upstream is recorded as having answered, reported nothing, or refused. Only “nothing to report” is ever shown as an absence. Records came from 124 datasets via GBIF.org; each carries its own licence.