ISOËTES

Isoëtes acadiensis Kott - Acadian Quillwort 2n = 44.

(The report of 2n = 44 (Kott and Britton 1980) for I. macrospora Durieu forma hieroglyphica (A. A. Eaton) N. E. Pfeiffer was later attributed (Kott 1981) to I. acadiensis). Shallow water of ponds and slow moving streams.

Isoëtes echinospora Durieu - Braun's Quillwort 2n = 22, 33.

Shallow water and shores of slightly acidic lakes, ponds, and streams. [I. echinospora var. braunii (Durieu) Engelmann; I. echinospora var. muricata (Durieu) Engelmann; I. muricata Durieu]

Isoëtes engelmannii A. Braun - Engelmann's Quillwort n = 11; 2n = 22.

Shallow water of ponds, lakes, streams, or in muddy ditches.

Isoëtes lacustris Linnaeus - Lake Quillwort 2n = 110.

Shores and shallow water of slightly acidic ponds, lakes, and streams. [I. macrospora Durieu; I. hieroglyphica A. A. Eaton]

Isoëtes prototypus D. M. Britton 2n = 22.

Deep water of cold, acidic lakes.

Isoëtes riparia Engelmann ex A. Braun - Riverbank Quillwort 2n = 44.

Muddy or sandy shores (including tidal shores and estuaries), usually of rivers. [I. riparia var. canadensis Engelmann; I. saccharata Engelmann var. amesii A. A. Eaton]

Isoëtes tuckermanii A. Braun ex Engelmann - Tuckerman's Quillwort 2n = 44.

Pond and lake margins, shores (frequently tidal), usually submersed in quiet water.

ISOËTES hybrids

Isoëtes x eatonii Dodge.

[= I. echinospora Durieu X I. engelmannii A. Braun; I. x gravesii A. A. Eaton; I. eatonii Dodge var. gravesii (A. A. Eaton) Clute]

Isoëtes x echtuckeri D. F. Brunton & D. M. Britton.

[= I. echinospora Durieu X I. tuckermanii A. Braun ex Engelmann]

Isoëtes x harveyi A. A. Eaton.

This hybrid was recognized only recently by Britton (1991). Herbarium specimens annotated as this hybrid are from southern Penobscot Co., Maine (US); Somerset Co., Maine (MAINE); and Mt. Desert Island, Maine (MO). Since the holdings of NEBC have not been examined critically for this hybrid, it is not mapped. [= I. lacustris Linnaeus X I. tuckermanii A. Braun]

DIPHASIASTRUM

Diphasiastrum complanatum (Linnaeus) Holub - Northern Running Pine n = 22-24, 23; 2n = 40, 44, 46, 48.

Dry, open coniferous or mixed forests. [Lycopodium complanatum Linnaeus]

Diphasiastrum digitatum (Dillenius ex A. Braun) Holub - Southern Running Pine n = 23; 2n = 46.

Usually dry woods, thickets, or open fields, in acid soils. [Lycopodium complanatum Linnaeus var. flabelliforme Fernald]

Diphasiastrum sitchense (Ruprecht) Holub - Sitka Clubmoss n = 23; 2n = 46.

Alpine meadows, open rocky barrens, conifer woods (rarely). [Lycopodium sitchense Ruprecht]

Diphasiastrum tristachyum (Pursh) Holub - Ground Cedar n = 23; 2n = 46.

Acid soils in open conifer or oak woods, thickets. [Lycopodium tristachyum Pursh]

DIPHASIASTRUM hybrids

Diphasiastrum digitatum (Dillenius ex A. Braun) Holub X Diphasiastrum x sabinifolium (Willdenow) Holub.

Diphasiastrum X habereri (House) Holub.

[= D. digitatum (Dillenius ex A. Braun) Holub X D. tristachyum (Pursh) Holub; Lycopodium x habereri House]

Diphasiastrum x issleri (Rouy) Holub.

[= D. alpinum (Linnaeus) Holub X D. complanatum (Linnaeus) Holub; Lycopodium xissleri (Rouy) Lawalrèe]

Diphasiastrum x sabinifolium (Willdenow) Holub - Savin-leaved Clubmoss 2n = 46.

Woods (often subalpine spruce), thickets, clearings. [= D. sitchense (Ruprecht) Holub X D. tristachyum (Pursh) Holub; Lycopodium sabinifolium Willdenow]

Diphasiastrum x verecundum A. V. Gilman.

[= D. complanatum (Linnaeus) Holub X D. digitatum (Dillenius ex A. Braun) Holub]

Diphasiastrum x zeilleri (Rouy) Holub.

[= D. complanatum (Linnaeus) Holub X D. tristachyum (Pursh) Holub]

HUPERZIA

Huperzia appressa (Desvaux) Á. Löve & D. Lõve - 2n = ca. 68.

Cliffs, talus slopes, damp, acidic rocks in alpine zones. [Lycopodium selago Linnaeus var. appressum Desvaux; The name Huperzia appressa Á. Löve & D. Lõve is here accepted only tentatively since a proper study of the Huperzia selago complex reviewing morphological and genetic evidence from specimens worldwide (including types) has not been done. The true status of Huperzia appressa (Desvaux) Á. Löve & D. Lõve, Huperzia appalachiana Beitel & Mickel, Huperzia selago var. densa Trevisan and Huperzia selago subsp.arctica (Tolmatchew) Á. Löve & D. Lõve can only be determined by such a study. Specimens mapped here are those filed as Huperzia appalachiana in the herbaria of the New England Botanical Club and Harvard University. Flora Europaea (http://rbg-web2.rbge.org.uk/FE/fe.html) includes var. appressum under H. selago subsp. arctica, while the Flora of NW Europe (http://nlbif.eti.uva.nl/bis/flora.php?) does not recognize H. appressa. A Chinese molecular study (Ji et. al., 2008) uses the name Huperzia appressa. Flora North America (1993) accepts Huperzia appalachiana without mention of appressa/appressum at any rank.]

Huperzia lucidula (Michaux) Trevisan - Shining Clubmoss n = 67; 2n = 134.

Cool, moist woods in rich and acid soils. [Lycopodium lucidulum Michaux]

Huperzia selago (Linnaeus) Bernhardi ex Schrank & Martius - Mountain Clubmoss n = 136II; 2n = 268.

Damp rocks, barrens, cold woods, in mountainous regions. [ Lycopodium selago Linnaeus]

HUPERZIA hybrids

Huperzia appressa (Desvaux) Á. Löve & D. Lõve x Huperzia lucidula (Michaux) Trevisan.

Huperzia x buttersii (Abbe) Kartesz & Gandhi.

[= H. lucidula (Michaux) Trevisan X H. selago (Linnaeus) Bernhardi ex Schrank & Martius]

Huperzia x josephbeitelii A. Haines.

[= H. appressa (Desvaux) Á. Löve & D. Lõve X H. selago (Linnaeus) Bernhardi ex Schrank & Martius]

LYCOPODIELLA

Lycopodiella alopecuroides (Linnaeus) Cranfill - Foxtail Clubmoss 2n = 156.

Bogs, marshes, ditches, sandy or peaty shores, wet barrens, in acid soils. [Lycopodium alopecuroides Linnaeus]

Lycopodiella appressa (Chapman) Cranfill - Appressed Bog Clubmoss 2n = 156.

Damp, acid or peaty soils in the open. [Lycopodium appressum (Chapman) Lloyd & Underwood; Lycopodium inundatum Linnaeus var. bigelovii Tuckerman]

Lycopodiella inundata (Linnaeus) Holub - Bog Clubmoss n = 78; 2n = 156.

Damp, acid, sandy, or peaty soils in the open. [Lycopodium inundatum Linnaeus]

Lycopodiella margueritae J. G. Bruce, W. H. Wagner, & Beitel. 2n = 312.
[The voucher for this species in New England has been re-identified as Lycpodiella inundata.]

LYCOPODIELLA hybrids

Lycopodiella x copelandii (Eiger) Cranfill

[= L. alopecuroides (Linnaeus) Cranfill X L. appressa (Chapman) Cranfill]

Lycopodiella x gilmanii A. Haines

[= L. appressa (Chapman) Cranfill X L. inundata (Linnaeus) Holub]

Lycopodiella x robusta (R. J. Eaton) A. Haines

[= L. alopecuroides (Linnaeus) Cranfill X L. inundata (Linnaeus) Holub; Lycopodium inundatum Linnaeus var. robustum R. J. Eaton]

LYCOPODIUM

Lycopodium annotinum Linnaeus - Stiff Clubmoss n = 34, 68II; 2n = ca. 50, 66, 68.

Woods, cool shaded thickets, exposed rocky or peaty habitats at higher elevations. [L. annotinum var. acrifolium Fernald; L. annotinum var. alpestre C. Hartman; L. annotinum var. pungens (Bachelot de la Pylaie) Desvaux]

Lycopodium clavatum Linnaeus - Staghorn Clubmoss
n = 22, 34, 34II, 34III, 34IV, 68 (69, 70); 2n = 34, 44, 68, 102, 136.

Open, usually dry, woods and thickets, clearings, exposed rocky situations, in acid soils. [L. clavatum var. subremotum Victorin]

Lycopodium dendroideum Michaux - Tree Clubmoss 2n = 68.

Dry, open woods and clearings. [L. obscurum Linnaeus var. dendroideum (Michaux) D. C. Eaton]

Lycopodium hickeyi W. H. Wagner, Beitel & R. C. Moran - Hickey's Clubmoss 2n = 68.

Mainly deciduous woods and thickets, usually in acid soils. [L. obscurum Linnaeus var. isophyllum Hickey]

Lycopodium lagopus (Laestadius ex C. Hartman) G. Zinserling ex Kuzeneva-Prochorova 2n = 68.

Grassy fields and openings in second-growth woods. [L. clavatum Linnaeus var. megastachyon Fernald & Bissell; L. clavatum Linnaeus var. monostachyon Hooker & Greville] Distribution data are primarily from the herbaria of the New England Botanical Club and Harvard University.

Lycopodium obscurum Linnaeus - Tree Clubmoss n = 34, 34II; 2n = 68.

Rich woods, clearings, edges of boggy forests, usually in acid soils.

LYCOPODIUM hybrids

Lycopodium dendroideum Michaux x Lycopodium obscurum Linnaeus.

PSEUDOLYCOPODIELLA

Pseudolycopodiella caroliniana (Linnaeus) Holub - Carolina Clubmoss n = 35, 68, 70, 115; 2n = 70, 78, 140.

Damp, open sands and peat in acid soils. [Lycopodium carolinianum Linnaeus]

SELAGINELLA

Selaginella apoda (Linnaeus) Spring ex Martius et al - Meadow Spikemoss 2n = 18.

Meadows, stream banks, moist lawns, wet rocks, often in circumneutral soils. [S. eclipes W. R. Buck]

Selaginella rupestris (Linnaeus) Spring - Rock Spikemoss 2n = 18.

Exposed, dry rocks or packed sands.

Selaginella selaginoides (Linnaeus) Palisot de Beauvois ex Martius & Schrank - Northern Spikemoss 2n = 18.

Damp shores and banks, bogs, springs, often calcareous.

EQUISETUM

Equisetum arvense Linnaeus - Field Horsetail n = 108; 2n = 200+, 216.

Open, low ground, roadsides, damp, open woods and thickets. [E. arvense var. boreale (Bongard) Ruprecht]

Equisetum fluviatile Linnaeus - Water Horsetail n = 108; 2n = 216.

Shores, shallow water of pond and river margins, swales.

Equisetum hyemale Linnaeus subsp. affine (Engelmann) Calder & Roy L. Taylor
- Common Scouring Rush n = 108.

Sandy banks and shores, alluvium, moist wooded slopes, roadsides. [E. hyemale var. affine (Engelmann) A. A. Eaton; E. hyemale var. pseudohyemale (Farwell) C. V. Morton]

Equisetum palustre Linnaeus - Marsh Horsetail n = 108.

Shores, flooded meadows, swamps, and marshes.

Equisetum pratense Ehrhart - Meadow Horsetail n = 108; 2n = 216.

Rich slopes in humus-rich neutral soils, meadows, alluvial thickets.

Equisetum scirpoides Michaux - Dwarf Scouring Rush n = 108.

Well-drained slopes, in cool woods, frequently under Tsuga, often growing in moss.

Equisetum sylvaticum Linnaeus - Wood Horsetail 2n = 216.

Cool moist woods, swamps, around springs. [E. sylvaticum var. pauciramosum Milde]

Equisetum variegatum Schleicher ex F. Weber & D. Mohr - Variegated Horsetail 2n = 216.

Riverbanks, shores, bog margins, moist gravel, and damp, calcareous sands.

EQUISETUM hybrids

Equisetum x ferrissii Clute.

Sandy shores, embankments, roadsides [= E. hyemale Linnaeus X E. laevigatum A. Braun; E. hyemale Linnaeus var. intermedium A. A. Eaton; E. hyemale Linnaeus var. elatum (Engelmann) C. V. Morton]

Equisetum x litorale Kuhlewein ex Ruprecht - Shore Horsetail.

Shores, ditches, meadows. [= E. arvense Linnaeus X E. fluviatile Linnaeus]

Equisetum x mackaii (Newman) Brichan 2n = 432.

Riverbanks, shores, bog margins, gravelly areas, damp, calcareous sands. [= E. hyemale Linnaeus X E. variegatum Schleicher ex F. Weber & D. Mohr; E. x trachyodon (A. Braun) Koch; E. variegatum Schleicher ex F. Weber & D. Mohr var. jesupii A. A. Eaton]

ASPLENIUM

Asplenium montanum Willdenow - Mountain Spleenwort 2n = 72.

Moist, sheltered crevices of chiefly non-calcareous cliffs and ledges.

Asplenium platyneuron (Linnaeus) Britton, Sterns & Poggenburg - Ebony Spleenwort n = 36, 36II.

Well-drained, rocky, circumneutral soils on slopes and ledges in deciduous forests (occasionally on crumbling mortar). [A. platyneuron var. incisum (E. C. Howe) B. L. Robinson]

Asplenium rhizophyllum Linnaeus - Walking Fern n = 36.

Shaded, basic or circumneutral rocks, rarely on earth or at tree bases. [Camptosorus rhizophyllus (Linnaeus) Link]

Asplenium ruta-muraria Linnaeus - Wall-rue n = 36, 72; 2n = 144.

Shaded crevices of calcareous cliffs and ledges. [A. cryptolepis Fernald; A. ruta-muraria var. cryptolepis (Fernald) Wherry]

Asplenium trichomanes Linnaeus - Maidenhair Spleenwort
n = 36, 36II, 36II + 36I, 72, 81, 108, 144; 2n = 72, 144, ca. 216.

Shaded crevices of mainly calcareous rocks (occasionally on crumbling mortar). [A. trichomanes subsp. quadrivalens D. E. Meyer]

Asplenium trichomanes-ramosum Linnaeus - Green Spleenwort n = 36; 2n = 72.

Shaded, moist crevices and talus of calcareous and serpentine rocks and outcrops. [A. viride Hudson]

ASPLENIUM hybrids

Asplenium x clermontae Syme 3x = 108.

[= A. ruta-muraria Linnaeus X A. trichomanes Linnaeus]

Asplenium x ebenoides R. R. Scott - Scott's Spleenwort 2n = 72, 144.

[= A. platyneuron (Linnaeus) Britton, Sterns, & Poggenburg X A. rhizophyllum Linnaeus; xAsplenosorus ebenoides (R. R. Scott) Wherry]

AZOLLA

AZOLLA CAROLINIANA Willdenow - Mosquito Fern n = 48; 2n = 44, 66.

Floating in quiet waters. From south of our range.

WOODWARDIA

Woodwardia areolata (Linnaeus) T. Moore - Netted Chain Fern n = 35.

Swamps and boggy woods in acid soils.

Woodwardia virginica (Linnaeus) Smith - Virginia Chain Fern n = 35, ca. 36.

Acid swamps, bogs, and wet, wooded bottoms.

DENNSTAEDTIA

Dennstaedtia punctilobula (Michaux) T. Moore - Hay-scented Fern n = ca. 33, 34.

Open woods, roadsides, stream banks, pastures and rocky slopes in sterile soils.

PTERIDIUM

Pteridium aquilinum (Linnaeus) Kuhn subsp. latiusculum (Desvaux) Hultén - Bracken n = 52; 2n = 104.

Clearings, pastures, burns, thickets and woods, usually in dry, sterile soils. [P. aquilinum var. latiusculum (Desvaux) L. Underwood ex A. Heller]

Pteridium aquilinum (Linnaeus) Kuhn subsp. pseudocaudatum (Clute) Hultén - Bracken.

Same habitats as in subsp. latiusculum. [P. aquilinum var. pseudocaudatum (Clute) A. Heller]

ATHYRIUM

Athyrium filix-femina (Linnaeus) Roth ex Mertens subsp. angustum (Willdenow) R. T. Clausen
- Lady Fern n = 40; 2n = 80.

Moist woods, thickets, ravines, fields, meadows and swamps. [A. filix-femina var. angustum (Willdenow) G. Lawson; A. filix-femina var. michauxii (Sprengel) Farwell]

Athyrium filix-femina (Linnaeus) Roth ex Mertens subsp. asplenioides (Michaux) Hultén
- Southern Lady Fern 2n = 80.

Moist woods, thickets, swamps, meadows. [A. filix-femina var. asplenioides (Michaux) Farwell]

ATHYRIUM NIPONICUM (Mettenius) Hance - Japanese Painted Fern 2n = 80.

From east Asia.

CYSTOPTERIS

Cystopteris bulbifera (Linnaeus) Bernhardi - Bulblet Fern n = 42; 2n = 42.

Calcareous, usually moist, ledges, steep banks, rocky slopes, and ravines.

Cystopteris fragilis (Linnaeus) Bernhardi - Fragile Fern n = 42, 84, 126; 2n = 168.

Moist rocks, rocky (mostly wooded) slopes.

Cystopteris laurentiana (Weatherby) Blasdell. n = 126; 2n = 252.

Cliffs, often calcareous. [C. fragilis (Linnaeus) Bernhardi var. laurentiana Weatherby] Distribution data were not collected for this taxon, since it was generally not distinguished from C. fragilis (Linnaeus) Bernhardi in New England herbaria.

Cystopteris protrusa (Weatherby) Blasdell - Southern Bladder Fern n = 42, 63.

Moist, often calcareous, wooded slopes, rocky banks, and alluvium. [C. fragilis (Linnaeus) Bernhardi var. protrusa Weatherby]

Cystopteris tenuis (Michaux) Desvaux - Mackay's Fragile Fern n = 84; 2n = 168.

Moist, shaded rocks, rocky (mostly wooded) slopes, alluvium, open woods. [C. fragilis (Linnaeus) Bernhardi var. mackayi G. Lawson]

CYSTOPTERIS hybrids

Cystopteris fragilis (Linnaeus) Bernhardi x Cystopteris tenuis (Michaux) Desvaux
n = 53II + 60I + 2III, 53I + 56I + 2 III, 52I + 64I.

Dry to moist cliffs and talus, moist ravines. Information for this hybrid is from Paler and Barrington (1995).

DEPARIA

Deparia acrostichoides (Swartz) M. Kato - Silvery Spleenwort n = 40; 2n = 80.

Rich moist woods, bottom lands, shaded slopes. [Athyrium thelypterioides (Michaux) Desvaux; Diplazium acrostichoides (Swartz) Butters]

DIPLAZIUM

Diplazium pycnocarpon (Sprengel) M. Broun - Narrow-leaved Spleenwort n = 40.

Moist, mostly calcareous, wooded slopes, ravines, and bottoms. [Athyrium pycnocarpon (Sprengel) Tidestrom; Homalosorus pycnocarpos (Sprengel) Small ex Pichi-Sermolli]

DRYOPTERIS

Dryopteris campyloptera (Kunze) Clarkson - Mountain Wood Fern n = 82; 2n = 164.

Moist, cool woods, thickets, and banks. [D. austriaca (Jacquin) Woynar ex Schinz & Thellung var. austriaca; D. spinulosa (O. F. Mueller) Watt var. americana (Fischer ex Kunze) Fernald; D. spinulosa (O. F. Mueller) Watt var. concordiana (Davenport) Eastman; D. austriaca (Jacquin) Woynar ex Schinz & Thellung var. concordiana (Davenport) Morton]

Dryopteris carthusiana (Villars) H. P. Fuchs - Spinulose Wood Fern n = 82; 2n = ca. 160, 164.

Low, moist (occasionally dry) woods and thickets, stream banks, swamps. [D. austriaca (Jacquin) Woynar ex Schinz & Thellung var. spinulosa (O. F. Mueller) Fiori; D. spinulosa (O. F. Mueller) Watt]

Dryopteris clintoniana (D. C. Eaton) Dowell - Clinton's Wood Fern n = 123; 2n = 246.

Wet (rarely only moist), often circumneutral woods and swamps. [D. cristata (Linnaeus) A. Gray var. clintoniana (D. C. Eaton) L. Underwood]

Dryopteris cristata (Linnaeus) A. Gray - Crested Wood Fern n = 41, 82, 123; 2n = 82, 164.

Swamps, wet woods, marshes, boggy thickets.

Dryopteris filix-mas (Linnaeus) Schott - Male Fern n = 82, 83; 2n = 41, 164.

Rocky wooded slopes, cold ravines, rich woods, upland pastures in chiefly calcareous soil, trap, or slate.

Dryopteris fragrans (Linnaeus) Schott - Fragrant Cliff Fern n = 41, 42.

Dry, often north-facing and calcareous, cliffs, ledges, talus, and rocky banks. [D. fragrans var. remotiuscula Komarov]

Dryopteris goldiana (Hooker ex Goldie) A. Gray - Goldie's Fern n = 41; 2n = 41.

Rich, moist woods, rocky slopes (mostly calcareous), ravines.

Dryopteris intermedia (Muhlenberg ex Willdenow) A. Gray - Glandular Wood Fern n = 41; 2n = 82.

Moist, rocky woods and moist thickets. [D. austriaca (Jacquin) Woynar ex Schinz & Thellung var. intermedia (Muhlenberg ex Willdenow) C. V. Morton; D. spinulosa (O. F. Mueller) Watt var. intermedia (Muhlenberg ex Willdenow) L. Underwood]

Dryopteris marginalis (Linnaeus) A. Gray - Marginal Shield Fern n = 41.

Rocky, usually rich, wooded slopes, ravines.

DRYOPTERIS hybrids

Dryopteris x benedictii Wherry.

[= D. carthusiana (Villars) H. P. Fuchs X D. clintoniana (D. C. Eaton) Dowell]

Dryopteris x boottii (Tuckerman) Underwood - Boott's Wood Fern n = 82, 123; 2n = 123.

Moist woods and thickets in mildly acid soils. [= D. cristata (Linnaeus) A. Gray X D. intermedia (Willdenow) A. Gray]. This common and widespread hybrid is not treated in Flora of North America (Flora of North America Editorial Committee 1993).

Dryopteris x burgessii Boivin.

[= D. clintoniana (D. C. Eaton) Dowell X D. marginalis (Linnaeus) A. Gray]

Dryopteris campyloptera (Kunze) Clarkson x Dryopteris intermedia (Muhlenberg ex Willdenow) A. Gray.

Dryopteris campyloptera (Kunze) Clarkson x Dryopteris marginalis (Linnaeus) A. Gray.

Dryopteris carthusiana (Villars) H. P. Fuchs x Dryopteris goldiana (Hooker ex Goldie) A. Gray.

There is one known collection for this taxon. Other collections so identified are variations of D. goldiana (report in preparation, W. H. Wagner, Jr., pers. comm.).

Dryopteris clintoniana (D. C. Eaton) Dowell x Dryopteris cristata (Linnaeus) A. Gray.

Dryopteris clintoniana (D. C. Eaton) Dowell x Dryopteris filix-mas (Linnaeus) Schott.

Dryopteris clintoniana (D. C. Eaton) Dowell x Dryopteris goldiana (Hooker ex Goldie) A. Gray.

Dryopteris x dowellii (Farwell) Wherry.

[= D. clintoniana (D. C. Eaton) Dowell X D. intermedia (Muhlenberg ex Willdenow) A. Gray]

Dryopteris filix-mas (Linnaeus) Schott x Dryopteris marginalis (Linnaeus) A. Gray.

Dryopteris goldiana (Hooker ex Goldie) A. Gray x Dryopteris intermedia (Muhlenberg ex Willdenow) A. Gray.

Dryopteris intermedia (Muhlenberg ex Willdenow) A. Gray xDryopteris marginalis (Linnaeus) A. Gray.

Dryopteris x neowherryi W. H. Wagner.

[= D. goldiana (Hooker ex Goldie) A. Gray X D. marginalis (Linnaeus) A. Gray]

Dryopteris x pittsfordensis Slosson.

[= D. carthusiana (Villars) H. P. Fuchs X D. marginalis (Linnaeus) A. Gray]

Dryopteris x slossoniae Wherry ex Lellinger.

[= D. cristata (Linnaeus) A. Gray X D. marginalis (Linnaeus) A. Gray]

Dryopteris x triploidea Wherry. 3n = 123.

Rocky or swampy (often rich) woods. [= D. carthusiana (Villars) H. P. Fuchs X D. intermedia (Muhlenberg ex Willdenow) A. Gray; D. austriaca (Jacquin) Woynar ex Schinz & Thellung var. fructuosa (Gilbert) C. V. Morton; D. spinulosa (O. F. Mueller) Watt var. fructuosa (Gilbert) Trudell]. This common and widespread hybrid is not treated in Flora of North America (Flora of North America Editorial Committee 1993).

Dryopteris x uliginosa (A. Braun ex Dowell) Druce.

[= D. carthusiana (Villars) H. P. Fuchs X D. cristata (Linnaeus) A. Gray]

GYMNOCARPIUM

Gymnocarpium dryopteris (Linnaeus) Newman - Oak Fern n = 40, ca. 73, 80; 2n = 80, 160.

Cool, moist, often rocky, woods and banks. [Dryopteris disjuncta (Ruprecht) C. V. Morton (misapplied)]

Gymnocarpium jessoense (Koidzumi) Koidzumi subsp. parvulum Sarvela - Nahanni Oak Fern 2n = 80, 160.

Acid or neutral substrates of cool talus slopes, cliffs and outcrops. This taxon also is reported to occur in Connecticut in Flora of North America (Flora of North America Editorial Committee 1993), but neither specimens nor specific citations of specimens in the literature have been seen. Kathleen Pryer (pers. comm.) indicates that the Connecticut report may be based on a mislabeled specimen.

MATTEUCCIA

Matteuccia struthiopteris (Linnaeus) Todaro - Ostrich Fern n = 39, 40; 2n = 78.

Alluvium, bottomland thickets, swamps and moist woods, often in circumneutral soils. [M. pensylvanica (Willdenow) Raymond; M. struthiopteris var. pensylvanica (Willdenow) C. V. Morton; Pteretis pensylvanica (Willdenow) Fernald]

ONOCLEA

Onoclea sensibilis Linnaeus - Sensitive Fern n = 37; 2n = 74.

Swamps, low woods, alluvial thickets, meadows, in neutral to slightly acid soils. [O. sensibilis var. obtusilobata (Schkuhr) Torrey]

POLYSTICHUM

Polystichum acrostichoides (Michaux) Schott - Christmas Fern n = 41; 2n = 82.

Rocky woods and slopes, occasionally swamps.

Polystichum braunii (Spenner) Fée - Braun's Holly Fern n = 82; 2n = 164.

Cool, damp, rocky woods, ravines, and banks in circumneutral soils. [P. braunii var. purshii Fernald; P. braunii subsp. purshii (Fernald) Calder & Roy L. Taylor]

POLYSTICHUM hybrids

Polystichum x potteri Barrington
n = 71I + 26II, 74I + 23II + 1III, 77I + 23II, 79I + 22II, 81I + 21II, 85I + 19II, 87I + 18II.

[= P. acrostichoides (Michaux) Schott X P. braunii (Spenner) Fée]

WOODSIA

Woodsia alpina (Bolton) S. F. Gray - Northern Woodsia n = 82; 2n = 156, 164.

Cool, calcareous (sometimes slaty) rock crevices. [W. alpina var. bellii Lawson]

Woodsia glabella R. Brown ex Richardson - Smooth Woodsia n = 39, ca. 40, ca. 82; 2n = 78, ca. 80.

Moist, shaded crevices of calcareous rocks.

Woodsia ilvensis (Linnaeus) R. Brown - Rusty Woodsia n = 39, 41; 2n = 78, 82.

Dry, often exposed, cliffs and talus.

Woodsia obtusa (Sprengel) Torrey - Blunt-lobed Woodsia n = 76.

Shaded ledges and rocky woods, mostly in calcareous soils.

WOODSIA hybrids

Woodsia x gracilis (Lawson) Butters.

[= W. alpina (Bolton) S. F. Gray X W. ilvensis (Linnaeus) R. Brown]

TRICHOMANES

Trichomanes intricatum Farrar - Appalachian Bristle Fern.

Sheltered, moist, noncalcareous rock crevices and other protected places in deep ravines and gorges. Known only as gametophytes.

LYGODIUM

Lygodium palmatum (Bernhardi) Swartz - Climbing Fern n = 30.

Damp thickets and woods, stream banks, in acid soils.

MARSILEA

MARSILEA QUADRIFOLIA Linnaeus - Water Clover n = 20; 2n = 40.

Lakes, ponds and quiet streams. From Europe.

BOTRYCHIUM

Botrychium dissectum Sprengel - Cut-leaved Grape Fern n = 45.

Woods, open thickets, clearings, sandy barrens. [B. dissectum Sprengel var. obliquum (Muhlenberg ex Willdenow) Clute]

Botrychium lanceolatum (S. G. Gmelin) Ångström subsp. angustisegmentum (Pease & A. H. Moore) R. T. Clausen
- Triangle Grape Fern n = 45; 2n = 90.

Moist, cool, rich woods, swamp margins, meadows, peaty slopes, clearings. [B. lanceolatum var. angustisegmentum Pease & A. H. Moore]

Botrychium lunaria (Linnaeus) Swartz - Common Moonwort n = 45; 2n = 90.

Open, gravelly or rocky slopes, pastures, meadows, shores, chiefly in calcareous soils.

Botrychium matricariifolium (Döll) A. Braun ex W. D. J. Koch - Daisyleaf Grape Fern n = 90.

Rich, usually moist, deciduous woods and thickets.

Botrychium minganense Victorin - Mingan Moonwort n = 90; 2n = 180.

Habitats similar to those of B. lunaria. [B. lunaria (Linnaeus) Swartz forma minganense (Victorin) Clute; B. lunaria var. minganense (Victorin) Dole]

Botrychium multifidum (S. G. Gmelin) Ruprecht - Leathery Grape Fern n = 45; 2n = 90, 180.

Peaty, sandy, or gravelly slopes, sparse woods, thickets, clearings, usually in acid soils. [B. multifidum var. intermedium (D. C. Eaton) Farwell]

Botrychium oneidense (Gilbert) House - Oneida Grape Fern n = 45; 2n = 90.

Moist, acidic woods and swamps. [B. dissectum Sprengel var. oneidense (Gilbert) Farwell; B. multifidum (S. G. Gmelin) Ruprecht var. oneidense (Gilbert) Farwell]. Distribution data were not collected for this taxon as it was inadequately distinguished from B. dissectum Sprengel and B. multifidum (S. G. Gmelin) Ruprecht in New England herbaria.

Botrychium pallidum W. H. Wagner 2n = 90. A species reported in Flora of North America (Flora of North America Editorial Committee 1993) as occurring in Maine; no voucher seen, no specific voucher for New England cited.

Botrychium rugulosum W. H. Wagner n = 45.

Open fields and secondary forests. We found no annotated vouchers for this relatively recently recognized taxon in New England herbaria. The distribution data are taken from W.H. Wagner, Jr. And F. S. Wagner (1982).

Botrychium simplex E. Hitchcock - Least Grape Fern n = 45.

Meadows, moist woods, edges of swamps and pastures, open shores, usually in poor soils. [B. simplex var. tenebrosum (A. A. Eaton) R. T. Clausen]

Botrychium virginianum (Linnaeus) Swartz - Rattlesnake Fern n = 92; 2n = 184.

Rich woods and thickets in neutral to slightly acid soils. [B. virginianum var. europaeum Angström]

OPHIOGLOSSUM

Ophioglossum pusillum Rafinesque - Northern Adder's Tongue n = 480; 2n = 960.

Peaty or grassy swales, meadows, damp thickets, damp sands. [O. vulgatum Linnaeus var. pseudopodum (S. F. Blake) Farwell]

OSMUNDA

Osmunda cinnamomea Linnaeus - Cinnamon Fern n = 22.

Swamps, damp thickets, stream banks, and other moist, shaded places in acid soils. [O. cinnamomea var. glandulosa Waters]

Osmunda claytoniana Linnaeus - Interrupted Fern n = 22; 2n = 44.

Moist woods, margins of swamps, moist thickets, occasionally in the open, in acid or neutral soils.

Osmunda regalis Linnaeus var. spectabilis (Willdenow) A. Gray - Royal Fern n = 22; 2n = 44.

Swamps, peaty thickets, shores, meadows, bogs, mostly in acid soils.

OSMUNDA hybrids

Osmunda cinnamomea Linnaeus X Osmunda claytoniana Linnaeus.

Osmunda x ruggii R. M. Tryon.

[= O. claytoniana Linnaeus X O. regalis Linnaeus var. spectabilis (Willdenow) A. Gray]

POLYPODIUM

Polypodium appalachianum Haufler & Windham - Appalachian Polypody n = 37; 2n = 74.

Cliffs and rocky slopes. [Data are from the herbaria of the New England Botanical Club and Harvard University.]

Polypodium virginianum Linnaeus - Common Polypody n = 74; 2n = 148.

On rocks, cliffs, tree bases, rocky (occasionally sandy) slopes, usually in acid soils. [P. vulgare Linnaeus var. virginianum (Linnaeus) D. C. Eaton]

POLYPODIUM hybrids

Polypodium x incognitum Cusick.

[= P. appalachianum Haufler & Windham X P. virginianum Linnaeus]

ADIANTUM

Adiantum aleuticum (Ruprecht) Paris - Aleutian Maidenhair Fern n = 29.

Serpentine barrens. [A. pedatum Linnaeus var. aleuticum Ruprecht; A. pedatum subsp. calderi Cody]

ADIANTUM HISPIDULUM Swartz - A species from Asia reported in Flora of North America (Flora of North America Editorial Committee 1993) as escaped in Connecticut; no voucher seen, no specific voucher for New England cited. n = 171.

Adiantum pedatum Linnaeus - Common Maidenhair Fern
n = 29, 58II, 57II + 2I, 56II + R4, 56II + chIV, 54I + 2II; 2n = 58, 60.

Rich, deciduous woods, in circumneutral or basic soil.

ADIANTUM hybrids

Adiantum x viridimontanum Paris n = 58.

[= A. aleuticum (Ruprecht) Paris X A. pedatum Linnaeus]

CHEILANTHES

Cheilanthes lanosa (Michaux) D. C. Eaton - Hairy Lip Fern n = 30.

Rocks and cliffs, calcareous or siliceous. [C. vestita (Sprengel) Swartz]

CRYPTOGRAMMA

Cryptogramma stelleri (S. G. Gmelin) Prantl - Slender Cliff-brake n = 30.

Shaded, moist, calcareous cliffs and rock ledges, typically in coniferous woods.

PELLAEA

Pellaea atropurpurea (Linnaeus) Link - Purple Cliff-brake n = 87.

Dry, exposed, calcareous rocks (occasionally on crumbling mortar), trap rock.

Pellaea glabella Mettenius ex Kuhn - Smooth Cliff-brake n = 116.

Dry, calcareous rocks and cliffs.

SALVINIA

SALVINIA NATANS (Linnaeus) Allioni - Floating Fern n = 18; 2n = 18, 36.

On still waters of ponds or slow streams. From Europe and Asia. [Records from New England are likely to be misidentified as S. rotundifolia Willdenow (Nauman 1993)]. This species is mentioned, but not treated in Flora of North America (Flora of North America Editorial Committee 1993).

PHEGOPTERIS

Phegopteris connectilis (Michaux) Watt - Long Beech Fern n = 60, 90; 2n = 90.

Rich, damp woods, cool, shaded, rocky banks, moist cliffs. [Dryopteris phegopteris (Linnaeus) C. Christensen; Thelypteris phegopteris (Linnaeus) Slosson]

Phegopteris hexagonoptera (Michaux) Fée - Broad Beech Fern 2n = 60.

Rich woods and thickets. [Dryopteris hexagonoptera (Michaux) C. Christensen; Thelypteris hexagonoptera (Michaux) Nieuwland]

THELYPTERIS

Thelypteris noveboracensis (Linnaeus) Nieuwland - New York Fern n = 27.

Moist woods and thickets. [Dryopteris noveboracensis (Linnaeus) A. Gray]

Thelypteris palustris Schott var. pubescens (Lawson) Fernald - Marsh Fern n = 35.

Swamps, low damp thickets, meadows, marshes, bogs, along ditches and streams. [Dryopteris thelypteris (Linnaeus) A. Gray var. pubescens (Lawson) Weatherby]

Thelypteris simulata (Davenport) Nieuwland - Massachusetts Fern n = 64.

Swampy or boggy woods and thickets, on knolls in bogs, in acid soils. [Dryopteris simulata Davenport]