Category Archives: Ferns

Spreading Wood Fern, Dryopteris expansa

Spreading Wood Fern               The Wood Fern Family—Dryopteridaceae

Dryopteris expansa Adans.

(dry-OP-ter-is  ex-PAN-suh)

Names:  Dryo- comes from a Greek word meaning tree, or more specifically oak—the same root as is found in the words dryad and druid.  Pteris means fern.  Expansa means expanding or spreading.  Botanical synonyms include D. austriaca, D. assimilis, and D. dilatata.  This species is also known as Arching, Northern, Spiny, Redwood, or Creekbank Wood fern; Northern, Alpine or Broad Buckler Fern; or Shield Fern.

Relationships: There are about 250 Dryopteris sp. in the temperate northern hemisphere.  They are generally called Wood Ferns, Male Ferns, or Buckler Ferns.  Many are popular ornamentals.  About 18 species are found in the mainland United States, (several naturally occurring hybrids, too), about a dozen are native to Hawaii.

Distribution of Spreading Wood Fern from USDA Plants Database

Distribution: Spreading Wood Fern is native throughout much of the temperate regions in the northern hemisphere, from the subarctic to high altitudes in southern mountains.  In the U.S. it occurs from Alaska to northern California, mostly west of the Cascades in Washington and Oregon; it also is found spottily in the Rocky Mountain States, in the Great Lakes region, and eastern Canada.

Growth: Spreading Wood Fern grows to 3 feet (1m)

Habitat: It grows in moist forests, streambanks, and mountain slopes. Wetland designation: FACW, It usually occurs in wetlands, but is occasionally found in non-wetlands.

Diagnostic Characters: Deciduous fronds are usually clustered and erect to wide-spreading. They are triangular to oblong shaped; 2-3 pinnate.  The lowest pinnae pair are usually longer, triangular and asymmetrical.  Spore cases are rounded, on the undersides of pinnae.  The erect or ascending rhizome often produces offshoots, which may be divided.

In the Landscape: Spreading Wood Fern is easy to grow and its fine-textured, lacy leaves are ideal for a woodland garden.

Use by natives: Northwest natives ate the rhizomes, baking them in pits overnight.  Pounded roots were applied to cuts.  The leaves were soaked and used to wash hair.  Eskimos removed the chaffy covering and boiled the fiddleheads and ate them with seal oil and dried fish or in soups.  The root has been used to treat internal parasites, such as tape worms.

Use by Wildlife: Spreading Wood Fern is eaten in small amounts by Blue Grouse and Mountain Goats.  Some Dryopteris sp. are used as a larval food plant for moths.

Links:

USDA Plants Database

Consortium of Pacific Northwest Herbaria

WTU Herbarium Image Collection, Plants of Washington, Burke Museum

E-Flora BC, Electronic Atlas of the Flora of British Columbia

Jepson Eflora, University of California

Calphotos

Ladybird Johnson Wildflower Center

USDA Forest Service-Fire Effects Information System

Plants for a Future Database

Native American Ethnobotany, University of Michigan, Dearborn

 

Other Wood Ferns:

Coastal Wood Fern, Dryopteris arguta, is more common in California and western Oregon but can be found in a few locales northwards to areas surrounding Vancouver, B.C.  It is also known as Marginal Wood Fern, or Western Shield Fern.  Arguta means sharp-toothed.  Coastal Wood Fern grows in moist forest edges, rocky sea cliffs and drier oak woodlands.  It has scale-like chaff on its leaf stalk and evergreen glandular leaves.  Fronds are feather-shaped, 20-60 cm. long, 1-pinnate; deeply cut pinnae have small, tiny teeth along their margins.

Spinulose Wood Fern, Dryopteris carthusiana, is widespread across temperate and arctic regions in the northern hemisphere.  It is also known as Toothed Wood Fern, Narrow Buckler Fern or Shield Fern.  Spinulose means having small spines; carthusiana means from the Chartreuse Mountains in the French Alps.  Deciduous, 20-70 cm long, fronds are narrow and 2-3 pinnate, with the lowermost pinnae about the same length as adjacent pinnae.  It is preferred moose forage.

Male Fern, Dryopteris felix-mas, is common throughout much of the northern hemisphere.  It is found throughout northeastern and western North America, only spottily in the Pacific Northwest.  Felix-mas means fruitful or happy male.  Deciduous, sometimes evergreen, non-glandular fronds are broadly lance-shaped, 20-120 cm long, and 1-2 pinnate.  This very popular garden ornamental grows vase-like and withstands some drought in shade.  Some cultivated varieties are available.  It is often used for cut flower arrangements.  It is considered poisonous, but the root has been used to expel tapeworms.

 

 


 

Lady Fern, Athyrium filix-femina

Lady Fern                                                                   The Wood Fern Family–Dryopteridaceae

 Athyrium filix-femina(L.) Roth

(a-THEER-ee-um  FIH-liks–FEH-min-uh)

Names:  Athyrium possibly comes from the Greek athyros, meaning doorless, referring to the late opening of the spore cases.  Filix-femina means fern-lady, referring to its delicate fronds in comparison to the Male Fern, Dryopteris filix-mas. (Felix means happy or fruitful/fertile; a happy or fruitful lady could also be an appropriate name for this aggressive fern!)

Relationships:  There are about 180 species of Athyrium worldwide; with only two species in the mainland United States.

 

 

Distribution of Lady Fern from USDA Plants Database

Distribution: Lady Fern is abundant throughout the northern hemisphere; found in all the states and provinces in North America.

 

 

 

Habitat: It grows in moist to wet forests, meadows and streambanks. Wetland designation: FAC, Facultative, it is equally likely to occur in wetlands or non-wetlands.

Growth: Lady Fern grows to 6 feet, (2m) tall.

 

Diagnostic Characters: It has large, feathery 2-3 pinnate fronds, tapering at both ends, arising from a cluster of scaly rhizomes.  Sori, or spore cases, are elongated and curved, oblong to horseshoe-shaped.

 

 

 

 

 

 

 

 

In the Landscape: This species, with its graceful, lacy, bright, yellow-green fronds, is very eye-catching.  It may, however be a little too aggressive for a formal garden, but is ideal for a wild, moist, woodland garden, where it can freely multiply.  It dies back completely in winter.  Some may consider the withered fronds a bit unsightly.

Use by people: Natives ate the roots/rhizomes after roasting or baking in a pit.  They should always be cooked prior to consumption; many ferns contain carcinogens, so caution is advised.  A tea made from the rhizomes or stems were used for various women’s complaints and to ease pain.  The leaves were used to cover camas while baking, to cover berry baskets and to wipe fish.

Use by Wildlife: Roosevelt Elk and deer Eat Lady Fern in the fall on the Olympic Peninsula, but it is not a major food species.  Grizzly Bears also eat the fronds.

Alpine Lady Fern, Athyrium americanum is found on open, rocky slopes along streams in our mountains.  It is also known as A. distentifolium var. americanum, or A. alpestre var. americanum.  It is much smaller, with narrower, crinkled fronds.

 

Links:

USDA Plants Database

Consortium of Pacific Northwest Herbaria

WTU Herbarium Image Collection, Plants of Washington, Burke Museum

E-Flora BC, Electronic Atlas of the Flora of British Columbia

Jepson Eflora, University of California

Calphotos

Ladybird Johnson Wildflower Center

USDA Forest Service-Fire Effects Information System

Native Plants Network, Propagation Protocol Database

Plants for a Future Database

Native American Ethnobotany, University of Michigan, Dearborn

 

Western Sword Fern, Polystichum munitum

Western Sword Fern                                   The Wood Fern Family–Dryopteridaceae

 Polystichum munitum (Kaulf.) C. Presl

(Pol-ee-STIK-um  mew-NEE-tum)

Names: Polystichum means many rows, referring to the arrangement of the spore cases on the undersides of the fronds.  Munitum means armed with teeth, referring to its toothed fronds.  Western Sword Fern is also known as Sword Holly Fern, Giant Holly Fern, Christmas Fern, Pineland Sword Fern, or Chamisso’s Shield Fern.

Relationships: There are about 260 species of Polystichum worldwide with about 16 native to North America; and about 10 native to the Pacific Northwest.

 

 

Distribution of Western Sword Fern from USDA Plants Database

Distribution: Western Sword Fern is found from southeast Alaska to the central California coast, mostly on the west of the Cascades; eastward to northern Idaho into northwest Montana.  Disjunct populations have been found in South Dakota and on Guadalupe Island off Baja California.

 

 

 

 

Growth: Western Sword Fern grows up to 4.5 feet (1.5m) tall.

Habitat:  It is usually found in moist forests, but it is probably the most adaptable of all our ferns and can take a bit more sun than other ferns and some dry periods. Wetland designation: FACU, it usually occurs in non-wetlands but occasionally is found in wetlands.

Sword Fern is very common in the understory in our westside forests.

Diagnostic Characters: Large, erect fronds form from a crown of scaly rhizomes.  Fronds are once-pinnate with alternate pointed, sharp-toothed leaflets; each leaflet with a small lobe pointed forward at the base.  Sori (spore cases) are large and round arranged in two rows on the undersides of the fronds halfway between the midvein and margins.

 

 

 

 

 

 

 

In the Landscape: Western Sword Fern is the most widespread and versatile of all our native ferns.  Although at home in woodlands, it often adapts to drier, sunnier sites in landscapes.  Its tall arching fronds are most impressive planted in drifts in a woodland garden.   When grown in the sun, the fronds are dwarfed and more erect; and have pinnae (leaflets) that are crisped and crowded so that they overlap and appear overlapping.  Young ferns are also more frilly-looking.

 

Phenology: Fronds partially unroll their “fiddleheads” by late May; by late July the spores are near maturity.

Sword Fern Fiddleheads.

 

 

 

 

 

 

 

 

Use by natives:  The roots/rhizomes were generally viewed by natives as a famine food. (This plant probably should only be consumed in small quantities, if at all, due to possible presence of carcinogens or other toxins.)  The rhizomes were peeled and then boiled or baked in a pit on hot rocks covered with fronds.  The fronds were used frequently for lining baking pits and storage baskets; and were spread on drying racks to prevent berries from sticking.  They were variously used for placemats, floor coverings, bedding; and for games, dancing skirts and other decorations.  They are frequently used today in flower arrangements.

Use by wildlife:  Western Sword Fern is browsed by deer, elk, Black Bear and Mountain Beaver; frequently eaten by Roosevelt Elk on the Olympic Peninsula. The fronds may be used as nesting material for rodents.

 

Western Sword Fern outcrosses frequently and hybrids have been identified from crosses with Anderson’s Holly Fern (P. andersonii), Mountain Holly Fern, (P. scopulinum) California Sword Fern (P. californicum), Shasta Fern (P. lemmonii), and Narrowleaf Sword Fern, (P. imbricans)

Links:

USDA Plants Database

Consortium of Pacific Northwest Herbaria

WTU Herbarium Image Collection, Plants of Washington, Burke Museum

E-Flora BC, Electronic Atlas of the Flora of British Columbia

Jepson Eflora, University of California

Calphotos

Ladybird Johnson Wildflower Center

USDA Forest Service-Fire Effects Information System

Hardy Fern Library

Native Plants Network, Propagation Protocol Database

Plants for a Future Database

Native American Ethnobotany, University of Michigan, Dearborn

 

Other Polystichum sp., native to the Pacific Northwest:

Narrowleaf Sword Fern, P. imbricans is similar to Western Sword Fern and once was classified as a variety of P. munitum.  It is smaller (20-60cm) with overlapping, somewhat infolded leaflets and only scarcely scaly stipes (petioles).  It is a better choice for a sunny spot.

Anderson’s Holly Fern, P. andersonii is much rarer; found in deep woods in the mountains.  Fronds grow to 1 meter.   It has a conspicuously chaffy fiddlehead and leaf stalk.  Pinnae are deeply cut making it appear doubly pinnate.  Bulblets form at the base of pinnae near the tip and may grow into a new plant when the frond touches the ground!

Anderson’s Holly Fern

Braun’s Holly Fern, P. braunii, is big (to 1m) and has twice pinnate leaves with no basal lobes. It grows in moist woodlands.  (Native to British Columbia, southern Alaska, the Idaho panhandle—Listed as threatened or endangered in several eastern U.S. states).

California Sword Fern, P. californicum, has finely toothed leaflets rather than the prominently toothed leaflets in Western Sword Fern; each tooth is short, ending abruptly. It will grow in a variety of habitats from moist, shaded woods to open slopes, and dry, rocky terrain.  It is rare in Washington & Oregon, listed as sensitive in Washington, only found in or near the Cascades in Pierce & Thurston counties).

Kruckeberg’s Holly Fern, P. kruckebergii is believed to be a fertile hybrid of P. lonchitis & P. lemmonii. It is found sporadically in the Cascades, Sierras, & Rocky Mountains on rocks and cliffs and is considered rare or imperiled in Alaska, Montana, Idaho, California and B.C.; and “of concern” in Oregon.  Fronds are about 10-25cm long.  Short leaflets are oval to triangular, overlapping and twisted; with teeth tipped with spines.  It is named after Dr. Arthur Kruckeberg, the well-known botanist and native plant gardener and enthusiast.

Kwakiutl Holly Fern, P. kwakiutlii is known only from the type specimen, collected at Alice Arm, British Columbia in 1934. It is presumed to be one of the diploid progenitors of P. andersonii.  It also produced bulblets, but differs from P. andersonii in its completely divided pinnae (leaflets).  Kwakiutl is a name applied to the native people in British Columbia on Vancouver Island and surrounding areas.

Lemmon’s or Shasta Holly Fern, P. lemmonii: Fronds are twice pinnate; pinnae have no spines and are overlapping and twisted, making it appear cylindrical.  This species grows in serpentine rock crevices; and is found sporadically in the Cascades from B.C. to northern California.  It is only known from one site in B.C. where it is listed as threatened.

Northern Holly Fern, P. lonchitis, grows in mountains, often in rock crevices, throughout much of the northern hemisphere.  Lonchitis is from the Greek logch meaning spear, referring to its spear-shaped leaves.  It is once pinnate with spiny leaflets; resembling a miniature Sword Fern.  It is listed as endangered in New York; and is on a review list in California.

Mountain Holly Fern or Rock Sword Fern, P. scopulinum is also like a smaller Sword Fern but is shinier and more leathery with spiny-toothed leaves.  It is nearly bipinnate with long hairs on the teeth of each leaflet.  It is found in dry coniferous forest or more commonly on cliffs and talus slopes.  It is more frequent east of the Cascades and the Rocky Mountains; it also grows in eastern Canada.

Alaska Holly Fern, P. setigerum, is presumed to a hybrid between P. munitum and P. braunii.  Fronds are 2-pinnate about the middle, finely spiny-toothed.  It is found in lowland coastal forests in Alaska and B.C.  It may be able find a niche in a cool, moist woodland garden.