Wetland indicators

The U.S. Fish and Wildlife Service, the principal federal agency dealing with information on wetlands, has over the years researched species of plants and their probability of being found in wetlands.

A product of this work are wetland indicators, which include five basic designations and options for gradients in between. The implications for landscapers is that the designations can suggest relative moisture requirements for plants. For example, a wetland species will almost certainly require constant moisture, while an upland species can manage with dryer habitats.

Codes have been assigned to many native species. A summary of names and definitions:

OBL - Obligate Wetland. Probably of 99 percent that it occurs naturally in wetlands.

FACW - Faculatitive Wetland. Usually found in wetland, with a probability of 67 to 99 percent, but occasionally is found in non-wetlands.

FAC - Facultative. Equally likely to be found in wetlands or non-wetlands, with a probability of 34 to 66 percent in wetlands.

FACU - Facultative Upland. Usually occurs in non-wetlands, with a probability of 1 to 33 percent of being found in wetlands.

UPL - Oblilgate Upland. Occurs almost always naturally in non-wetlands, probability of 99 percent.

Occasionally found is the indicator "NI," which means insufficient information is available to assign an indicator status.

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Ferns and fern allies for the Poconos

Introduction

More than 80 species of ferns and fern allies (i.e., club mosses and horsetails) are considered native to Pennsylvania and identified as having distribution in the northeastern counties. Of them, 47 species are reported as commercially available from a variety of reputable nurseries within the United States and 37 appear to be unavailable.

Many of those which are not available are rare, have highly specific habitat requirements, or are natural hybrids of species found in the wild. The most dramatic landscape ferns are common in the marketplace.

Three species are unpalatable to deer and aggressive spreaders, making them ideal woodland alternatives to lawns (no mowing, no leaf raking, no fertilizing, thrive in acidic dry shade, and conservation of water all at once). Forming vast colonies of green are:

  • Dennstaedtia punctilobula (Hayscented fern)
  • Pteridium aquilinum (Northern bracken fern)
  • Thelypteris noveboracensis (New York fern)

Criteria for listing the species here are:

  • Availability at least by mail order as seed or live plants from a legitimate nursery in the United States
  • Reported as native to Pennsylvania and identified as being found in Carbon, Monroe, Pike or Wayne Counties, especially in all or several. This suggests the region contains suitable habitat for the species to be successfully grown.

Data presented for each species includes the currently-recognized Latin name, a popular common name, an indication of where the plant is typically found in nature, suggestions on suitable garden sites and care, soil pH when available, and wetlands indicators from the U.S. Fish and Wildlife Service if available.

 

Adiantum pedatum

Northern maidenhair is found in rich, deciduous woodlands, often on humus-covered talus slopes and moist lime soils; FAC-. Fronds 12-30 inches; rhizome: short creeping. Grow in part shade to shade in moist sandy organic loam, pH 5-7.

Asplenium platyneuron

Ebony spleenwort is found on the forest floor or on rocks, often invading masonry and disturbed soils; FACU. Fronds 8-18 inches; rhizome: short creeping to ascending. Grow in part shade to shade in dry to moist sandy clay loam, pH 5-7.5.

Asplenium trichomanes

Maidenhair spleenwort is found on acidic rocks such as sandstone, basalt, and granite, very rarely on calcareous rocks. Fronds 4-7 inches; rhizome: short creeping to ascending. Grow in part shade to shade in dry to moist rocky, humusy loam, pH 4-7.5.

Athyrium felix-femina

Lady fern is found in wooded valleys along streams, on rich wooded slopes and on floors of ravines, swamps, moist meadows and thickets; FAC. Fronds 12-24 inches; rhizome: erect or ascending in clumps. Grow in sun to part shade in moist rich sandy loam, pH 4-7.

Botrychium virginianum

Rattlesnake fern is found in moist shaded forests, wooded slopes and shrubby second growth, rare or absent in arid regions; FACU. Fronds 6-20 inches, rhizome: erect, subterranean. Grow in part shade to shade in moist rich sandy loam, pH 4-6.

Camptosorus rhizophyllus

Walking fern is found in shaded, usually moss-covered boulders and ledges, usually on limestone or other basic rocks, but occasionally on sandstone or other acidic rocks, rarely on fallen tree trunks. Fronds 4-10 inches; rhizome: ascending. Grow in part shade to shade in dry to moist calcareous loam, pH 6.5-7.5.

Cheilanthes lanosa

Hairy lip fern is found on rocky slopes and ledges, on a variety of substrates including limestone and granite, mostly eastern Poconos. Fronds 6-16 inches; rhizome: short creeping. Grow in part sun to shade in dry sandy loam, pH 5-6.

Cystopteris bulbifera

Bublet bladder fern is found mostly on moist calcareous cliffs, but also grows on rock in dense woods and occasionally occurs terrestrially in northern swamps; FAC. Fronds 18-36 inches; rhizome: short creeping. Grow in part shade to shade in moist calcareous loam, pH 6.5 to 7.5.

Cystopteris fragilis

Fragile fern is found mostly on cliff faces, also in thin alkaline soil over rock; FACU. Fronds 5-16 inches; rhizome: compact. Grow in part shade to shade in moist to wet garden soil.

Dennstaedtia punctilobula

Hay scented fern is found on rocky slopes, meadows, woods, stream banks, and roadsides, in acid soils. Fronds 15-30 inches, rhizome: very long-creeping. Grow in sun to part shade in dry, well drained sandy and acidic loam, pH 4-6. Aggressive spreader; forms vast colonies, especially where deer pressure is high because deer ignore it.

Deparia acrostichoides

Silvery glade fern is found along stream bottoms and river bank and damp woods, often on shaly slopes; FAC. Fronds to 40 inches; rhizome: short creeping. Grow in part sun to shade in moist acidic sandy loam, pH 5-7 but prefers 5 to 5.7.

Diphasiastrum tristachyum

Deep-rooted running-pine is found in sterile, acidic soils in open coniferous forests and oak forests, sandy barrens and clearings. Stems 6-12 inches; rhizome: short creeping. Grow in part shade to shade in moist acidic humusy loam.

Diplazium pycnocarpon

Narrow-leaved glade fern is found in wooded glades and alluvial thickets, neutral soil, but not in ridge and valley provinces; FAC. Fronds 18-40 inches; rhizome: short creeping. Grow in part shade in moist organic circumneutral garden loam.

Dryopteris carthusiana

Spinose wood fern is found in swampy woods, moist wooded slopes, stream banks, and conifer plantations; FAC+. Fronds 12-36 inches; rhizome: ascending crown. Grow in part sun to shade in moist organic loam.

Dryopteris clintoniana

Clinton's wood fern is found in deep humus in swampy woods, especially maple swamps. Prefers wet mucky woods, thickets; FACW+. Fronds 24-48 inches; rhizome: short creeping. Grow in part shade to shade in moist to wet rich silty loam, pH 4-6.

Dryopteris cristata

Crested shield fern is found in swamps, swampy woods, or open shrubby wetlands; prefers wet mucky woods, thickets; FACW+. Fronds 12-36 inches, rhizome: short creeping. Grow in part shade to shade in moist rich silty loam, pH 4-6.

Dryopteris goldiana

Goldie's wood fern is found in dense, moist woods, especially ravines, limey seeps, or at the edge of swamps, in deep humus; FAC+. Fronds 36-48 inches, rhizome: short creeping. Grow in part shade to shade in moist rich humusy loam, pH 4-7.

Dryopteris intermedia

Evergreen wood fern is found in moist rocky woods, especially hemlock hardwoods, ravines, and edges of swamps; FACU. Fronds 18-36 inches. Rhizome: erect crown Grow in part shade to shade in moist organic loam, pH 4.5 to 7.5.

Dryopteris marginalis

Marginal wood fern is found on rocky, wooded slopes and ravines, edges of woods, stream banks and road banks, and rock walls. Fronds 18-30 inches, rhizome: erect crown. Grow in part sun to shade in moist rich sandy loam, pH 5-6

Equisetum arvense

Field horsetail is found in moist roadsides, riverbanks, fields, marshes, pastures, and tundra; FAC. Stems 8-18 inches, rhizome: long creeping. Grow in sun to part sun in moist rich sandy loam.

Equisetum fluviatile

Water horsetail is found in standing in water, in ponds, ditches, marshes, swales, edges of rivers and lakes; OBL. Stems 24-26 inches; rhizome: short creeping. Grow in sun to part sun in ponds and pond edges or frequently inundated or poorly drained low area with a base of silty loam.

Equisetum hyemale var. affine

Scouring-rush is found on riverbanks, lakeshores and woodlands; moist sandy and gravelly slopes; stream banks, embankments and roadsides; FACW. Stems 14-48 inches; rhizome: creeping. Grow in sun to part shade in rich moist sandy loam. Can be difficult to control because of deep rhizomes.

Equisetum sylvaticum

Woodland horsetail is found in moist open woods and wet meadows; FACW. Stems 10-30 inches. Rhizome: creeping. Grow in sun to part shade in moist sandy clay loam.

Gymnocarpium dryopteris

Common oak fern is found in cool, coniferous and mixed woods and at base of shale talus slopes often in pockets of humus; UPL. Fronds 9-12 inches; rhizome: wide or long creeping. Grow in part shade to shade in moist rocky humus.

Lycopodium annotinum

Bristly clubmoss is found in swampy or cool shaded often moist coniferous forests, mountain forests, and exposed grassy or rocky sites; FAC. Stems 2-10 inches; rhizome: long creeping. Grow in part sun to shade in mesic to moist rich acidic humus.

Lycopodium clavatum

Common clubmoss is found in bogs, open woods and rocky barrens; FAC. Stems 2-10 inches; rhizome: long creeping. Grow in part sun to part shade in mesic rich acidic humus.

Lycopodium obscurum

Flat branched ground pine is found in rich hardwood forests and successional shrubby areas; FACU. Stems 8-10 inches; rhizome: long-creeping. Grow in part shade to shade in mesic to moist rich acidic humus.

Lygodium palmatum

Climbing fern or Hartford fern is found in moist thickets, barrens, swamp edges, open woods, acidic, poorly drained and peaty soil; FACW. Twining, climbing to 15 feet; rhizome: short creeping. Grow in full shade in acidic, peaty sandy loam, pH 4-7. Can be difficult to grow.

Matteuccia struthiopteris

Ostrich fern is found in rich humus on rocky stream banks, moist alluvial flats, floodplains, mucky swamps and rich woods; FACW. Fronds 24-72 inches; rhizome: erect, but with wide reaching stolons. Grow in part sun to shade in moist organic loams. pH 5 to 7.5. Dramatic vase-like habit, but forms extensive colonies via multiple stolons.

Onoclea sensibilis

Sensitive fern is found in open swamps, thickets, marshes, or low woods, in muddy soil in sunny wet meadows or shaded stream bank locations, often forming thick stands; FACW. Fronds 12-36 inches; rhizome: short creeping. Grow in part sun to shade in moist silty humusy loams, pH 4.5 to 7.5 but prefers acidic soil.

Osmunda cinnamomea

Cinnamon fern is found in swamps, stream banks, roadsides, Moist areas, acidic soils, frequently in vernal seeps, ponds and swamps; FACW. Fronds 30-60 inches; rhizome: erect with occasional offshoots. Grow in part sun to part shade in moist acidic organic humusy to silty soils, pH 5.5 to 7.

Osmunda claytoniana

Interrupted fern is found in oozy mud swamps, bogs, and stream banks; also, rich, mesic woods and open woods and shaded roadsides; FAC. Fronds 24-48 inches; rhizome: erect with occasional offshoots. Grow in part sun to part shade in rich mesic to moist silty loam, pH 4-6.

Osmunda regalis

Royal fern is found in swamps, bogs, bluffs, stream banks in moist acidic soils; OBL. Fronds 24-60 inches; rhizome: erect with occasional offshoots. Grow in part sun to part shade in moist to wet silty organic loam, pH 4-6.

Pellaea atropurpurea

Purple cliffbrake is found in dry soils adjacent to dolomite glades and crevices of limestone and dolomite outcrops, bluffs, boulders and sink holes. Fronds 8-20 inches; rhizome: short creeping. Grow in part sun to part shade in dry to mesic sandy loam, pH 5.5 to 7.5 but prefers 6.5 to 7.5

Phegopteris connectilis

Long or narrow beech fern is found in cool shade, woods in moist loose humus, strongly to moderately acid soil, or on rocks in shaded rock crevices. Fronds 8-18 inches; rhizome: medium creeping. Grow in part shade to shade in mesic to moist rocky sandy humusy loam, pH 4 to 6.

Phegopteris hexagonoptera

Broad beech fern is found in moist woods, usually in full shade, often in moderately acid soils; FAC. Fronds 12-24 inches, rhizome: long creeping. Grow in part shade to shade in moist acidic garden loam.

Polypodium virginianum

Common polypody is found on rocks, boulders, cliffs, ledges, rocky woods; on a variety of substrates. Fronds 4-14 inches; rhizome: sort to medium creeping. Grow in part shade to shade in moist rich loam, pH 4 to 6.

Polystichum acrostichoides

Christmas fern is found on forest floors and shady, rocky slopes in organically rich, dry to medium wet, well-drained soil. Fronds 12-24 inches; rhizome: multiple crown. Grow in part shade to shade in dry to moist sandy rich loam, pH 4 to 7.

Polystichum braunii

Braun's holly fern is found in moist places in boreal forests; interior moist forests; cool rocky shaded ravines. Fronds 8-36 inches; rhizome: clump-forming. Grow in part shade to shade on cool sites in peaty, humusy moist loam.

Pteridium aquilinum

Northern bracken fern is found in sunny to partly shaded dry areas with infertile soil in barrens, pastures, and open woodlands in moderately to strong acid soil, abundant, forming large colonies; FACU. Fronds 18-50 inches; rhizome: very long creeping. Grow in sun to part shade in dry to mesic sterile sandy loam, pH 4 to 5. Unpalatable to deer; aggressive spreader and forms large colonies.

Selaginella apoda

Meadow spikemoss is found in swamps, meadows, marshes, pastures, damp lawns, open woods, and stream banks, in basic to acidic soil; FACW. Mat forming, low creeping multi-branched rhizome. Grow in part sun to part shade in moist to wet rich loam.

Thelypteris noveboracensis

New York fern is found in terrestrial in moist woods, especially near swamps, streams, and in vernal seeps of ravines, often in slightly disturbed secondary forests, frequently forming large colonies; prefers dry oak, beech, maple and birch woods; FAC. Fronds 12-24 inches; rhizome: long creeping. Grow in high shade in mesic to moist humus rich sandy loam, pH 4 to 6. Aggressive spreader and can become invasive, forming huge woodland colonies.

Thelypteris palustris var. pubescens

Marsh fern is found in swamps, bogs, and marshes in soft rich muddy soil, also along riverbanks and roadside ditches, and in wet woods; FACW. Fronds 18-30 inches; rhizome: long creeping. Grow in part sun to part shade in moist to wet rich silty loam, pH 4 to 7 but prefers 4.5 to 6.5.

Woodsia ilvensis

Rusty woodsia is found on sunny cliffs and rocky slopes, usually in contact with rock; found on variety of substrates. Fronds 3-8 inches; rhizome: erect to ascending. Grow in part sun to part shade in moist to wet acidic garden soil, pH 5 to 6.

Woodsia obtusa

Blunt lobed woodsia is found on cliffs and rocky slopes (rarely terrestrial); found on a variety of substrates including both granite and limestone. Fronds 5-15 inches; rhizome: short creeping or ascending. Grow in part sun to part shade in dry to mesic sandy humusy loam, pH 5 to 7.5.

Woodwardia areolata

Netted chain fern is found in acidic bogs, seeps, and wet woods; FACW. Fronds 12-24 inches, rhizome: long-creeping. Grow in part sun to part shade in moist to wet rich loam.

Woodwardia virginica

Virginia chain fern is found in acidic swamps, marshes, bogs, and roadside ditches over noncalcareous substrates; OBL. Fronds 18-24 inches; rhizome: long creeping. Grow in high shade to dappled shade in acidic moist to wet garden soil.