Articles on this page are available in 1 other language: Spanish (3) (learn more)

Overview

Brief Summary

Introduction

Bracken (Pteridium aquilinum) is a conspicuous fern that forms large clonal colonies in a variety of habitats. The large, more or less triangular leaves develop from fiddleheads that develop widely spaced along the branches of an extensive subterranean rhizome that may reach nearly 400 m in length. The taxonomy of the genus remains controversial, but most botanists currently favor a classification involving five or more species. In this sense, Pteridium aquilinum is distributed widely in mostly the northern hemisphere, in both the New and Old Worlds.

Bracken produces a pharmacopeia of toxic compounds, including: thiaminase (which breaks down the amino acid thiamine and results in vitamin B deficiency), ecdysomes (hormones that stimulate uncontrolled early molting in insects), tannins (which bind to proteins and other compounds), and hydrogen cyanide, and also produces carcinogenic compounds. The combination of chemicals renders the plants toxic to most animals, both invertebrates and vertebrates, although some insect specialists ingest bracken tissue to become poisonous to their predators. Humans have long eaten the fiddleheads (emerging young leaves) of bracken, but over-ingestion of fresh or dried fronds has been linked to stomach and esophageal cancers.

Bracken is an aggressive colonizer of disturbed and other successional habitats and has been considered an invader of pastureland. It has been shown to be allelopathic (to produce compounds that inhibit the growth of other plant species) and can for dense monocultures. It is difficult to eradicate or control and, because it is toxic, renders such pasturage unfit for grazing. Pteridium aquilinum is considered a noxious weed, especially in portions of Great Britain and mainland Europe.

Creative Commons Attribution 3.0 (CC BY 3.0)

Missouri Botanical Garden

Trusted

Article rating from 2 people

Average rating: 3.75 of 5

Biology

Curled bracken shoots first appear in May, and are vulnerable to late frosts at this time (5). This species reproduces by means of spores, which are released from the brown spore-cases on the undersides of the fronds (5). It can also spread by vegetative reproduction, from a subterranean creeping storage organ known as a rhizome (2). When cut in half, the rhizome is said to display a pattern reminiscent of an oak tree, or outspread eagle wings (which may account for the specific name, aquila, which means eagle). It was also believed that letters could be seen in the patterns inside a rhizome; these were thought to show the initials of a future spouse (5). This fern also became associated with invisibility, although the reason is not entirely clear. It has been suggested that the lack of flowers may have fuelled the association; the mysterious absence of flowers was once thought to be magical (6). This species has been put to a wide range of practical uses, as manure, mulch, tinder, and fuel; in 18th Century Scotland it was burned to obtain potash needed for glass and soap manufacture, and it was (and still is in some areas) used as a bedding for livestock (6). One of its main uses, however, was as a packaging material (6). As these applications have declined, bracken cutting has ceased in many areas, and the species has spread dramatically as a result (6). Although livestock tend to avoid bracken, as it is extremely toxic, in dry years when there is very little else to eat livestock may browse on bracken, often with fatal results (6).
Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© Wildscreen

Source: ARKive

Trusted

Article rating from 1 person

Average rating: 3.0 of 5

Interesting Facts

Archaeologists excavating a ca. 30 m2 stable associated with Hadrian’s Wall in England (Roman, ca. 100 AD) found more than 250,000 puparia of the stable fly (Stomoxys calcitrans). Subsequently it was discovered that most of the larvae had pupated prematurely, before reaching full developmental maturity. The most likely cause of this phenomenon is that bracken was a major component of the plant litter used to line the floors of such structures, a testament to the efficacy of the insecticidal ecdysomes in the bracken. For a fascinating narrative on this situation and other aspects of bracken toxicology, see Robbin Moran’s (2004) excellent book, A Natural History of Ferns.

Creative Commons Attribution 3.0 (CC BY 3.0)

George Yatskievych

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Succinct

Medium- to large-size fern with an extensive underground rhizome, forming large colonies of broad, 2- to 4- times divided leaves.
Creative Commons Attribution 3.0 (CC BY 3.0)

George Yatskievych

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Comprehensive Description

Description

Rhizome widely creeping, subterranean, 5-10 mm in diameter; scales brown, very fine, up to 1 mm long. Fronds widely spaced, stiff, erect, hard, subglabrous, 0.5 - 1.75 m tall. Stipe up to 0.5 m long, underground portion swollen and covered with fine, brown hairs, above-ground portion pale-green, glabrous. Lamina 3-pinnatifid to 4-pinnate, triangular in outline. Pinnae stand out from the rhachis horizontally at nearly right angles. Basal pinnae as long as the frond; pinnae in the upper half 2-pinnate. Pinnules deeply incised, adnate to the costules and with apices that are long and narrow. Sori linear, continuous, situated just inside the inrolled margins; pseudo-indusium continuous. 
Creative Commons Attribution Non Commercial 3.0 (CC BY-NC 3.0)

© Mark Hyde, Bart Wursten and Petra Ballings

Source: Flora of Zimbabwe

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Derivation of specific name

aquilinum: of an eagle; either because the spreading pinnae resemble the wings of an aegle or a reference to the shape of the vascular bundle in the stipe.  
Creative Commons Attribution Non Commercial 3.0 (CC BY-NC 3.0)

© Mark Hyde, Bart Wursten and Petra Ballings

Source: Flora of Zimbabwe

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Description

Rhizome widely creeping, subterranean, 5-10 mm in diameter; scales brown, very fine, up to 1 mm long. Fronds widely spaced, stiff, hard, erect, pubescent fronds, 0.5-1.75 m tall, often forming large, dominant colonies in suitable habitats. Stipe up to 0.5 m long, underground portion swollen and covered with fine, brown hairs, above-ground portion pale-green, glabrous. Lamina 3-pinnatifid to 4-pinnate, triangular in outline. Pinnae standing out from the rhachis horizontally at nearly right angles; basal pinnae half as long as the frond; pinnae in the upper half 3-pinnatifid. Pinnules deeply incised, joined to the costules, with apices that are not long and narrow. Sori linear, continuous, situated just inside the inrolled margins; pseudo-indusium continuous.
Creative Commons Attribution Non Commercial 3.0 (CC BY-NC 3.0)

© Mark Hyde, Bart Wursten and Petra Ballings

Source: Flora of Zimbabwe

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Derivation of specific name

aquilinum: of an eagle; either because the spreading pinnae resemble the wings of an aegle or a reference to the shape of the vascular bundle in the stipe. 
capense: of the Cape
Creative Commons Attribution Non Commercial 3.0 (CC BY-NC 3.0)

© Mark Hyde, Bart Wursten and Petra Ballings

Source: Flora of Zimbabwe

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Nomenclatural History

Pteridium aquilinum was well-known to botanists in pre-Linnaean times, and Linnaeus (1753) cited older European literature sources in his description of Pteris aquilina. Maximilian Kuhn (1879), who studied pteridophyte specimens made during the African expedition of Baron Carl Claus von der Decken, determined that Pteris aquilina was best transferred to Pteridium, which had been described as a genus without a list of constituent species by Scopoli (1760). Pteridium aquilinum is thus the type species of the genus Pteridium Gled. ex Scop.

Creative Commons Attribution 3.0 (CC BY 3.0)

George Yatskievych

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Specimen Information

See GBIF. It should be noted that misdetermined or incompletely determined specimens in this difficult genus may result in spurious distributional data.
Creative Commons Attribution 3.0 (CC BY 3.0)

George Yatskievych

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Original Description

Basionym: Pteris aquilina L., Species Plantarum 2: 1075.
Linnaeus, C. 1753. Species Plantarum : Exhibentes Plantas Rite Cognitas, Ad Genera Relatas, cum Differentiis Specificis, Nominibus Trivialibus, Synonymis Selectis, Locis Natalibus, Secundum Systema Sexuale Digestas, vol. 2. Impensis Laurentii Salvii, Stockholm.

Combination: Pteridium aquilinum (L.) Kuhn, Botanik von Ost-Afrika 3(3): 11. 1879
von der Decken, C. C. 1869–1879. Baron Carl Claus von der Decken’s Reisen in Ost-Afrika in den Jahren 1859 bis 1861, 4 vols in 6 pts. C. F. Winter, Leibzig. [vol. 3, in 3 parts (1869–1879), = Beiträge zur Botanik, by various contributors]

Creative Commons Attribution 3.0 (CC BY 3.0)

George Yatskievych

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Distribution

Worldwide distribution

Angola, Burundi, Congo, DRC, Gabon, Malawi, Mozambique, Rwanda, Tanzania, Zambia, Zimbabwe.
Creative Commons Attribution Non Commercial 3.0 (CC BY-NC 3.0)

© Mark Hyde, Bart Wursten and Petra Ballings

Source: Flora of Zimbabwe

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Worldwide distribution

This subspecies is widespread in tropical Africa & South Africa, also in Madagascar, Mauritius and Réunion. The species as a whole is one of the most cosmopolitan fern species.
Creative Commons Attribution Non Commercial 3.0 (CC BY-NC 3.0)

© Mark Hyde, Bart Wursten and Petra Ballings

Source: Flora of Zimbabwe

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

National Distribution

Canada

Origin: Native

Regularity: Regularly occurring

Currently: Present

Confidence: Confident

United States

Origin: Native

Regularity: Regularly occurring

Currently: Present

Confidence: Confident

Creative Commons Attribution Non Commercial 3.0 (CC BY-NC 3.0)

© NatureServe

Source: NatureServe

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Occurrence in North America

     AL  AK  AZ  AR  CA  CO  CT  DE  FL  GA
     HI  ID  IL  IN  IA  KS  KY  LA  ME  MD
     MA  MI  MN  MS  MO  MT  NE  NV  NH  NJ
     NM  NY  NC  ND  OH  OK  OR  PA  RI  SC
     SD  TN  TX  UT  VT  VA  WA  WV  WI  WY
     AB  BC  MB  NB  NF  NS  ON  PE  PQ  YT
     MEXICO

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

More info for the term: fern

Western bracken fern occurs throughout the world with the exception of hot and
cold deserts [189].  Subspecies aquilinum is mostly north temperate in
distribution; subspecies caudatum is found primarily in the Southern
Hemisphere [189].  The distribution of subspecies and varieties found in
the United States and Canada is as follows [72,90,119,174,189,232]:

P. a. var. pubescens is found in western North America and ranges south
from southern Alaska through California and into Mexico and east into
Alberta, Montana, western South Dakota, Wyoming, Colorado, and western
Texas.  There are outlier populations in Quebec, Ontario, and northern
Michigan.

P. a. var. pseudocaudatum is primarily along the eastern coastal plain of
the United States from Cape Cod to Florida.  It is less frequent to the
west but extends across the southern states to Texas, southeastern
Kansas, and as far north as Illinois.

P. a. var. latiusculum is basically circumboreal in range, growing across
northern Europe, northern Asia and Japan, and much of North America, but
it has not been found in western North America.  It grows from
Newfoundland west to northeastern North Dakota, and south to North
Carolina, Oklahoma, and Tennessee.  There are occasional outlier
populations in Mississippi, Wyoming, South Dakota, and Colorado. 

P. a. var. decompositum is restricted to the Hawaiian Islands.

P. a. var. caudatum is present in Bermuda, southern Florida, the West
Indies, Central America, and into northern South America.

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Regional Distribution in the Western United States

More info on this topic.

This species can be found in the following regions of the western United States (according to the Bureau of Land Management classification of Physiographic Regions of the western United States):

    1  Northern Pacific Border
    2  Cascade Mountains
    3  Southern Pacific Border
    4  Sierra Mountains
    5  Columbia Plateau
    6  Upper Basin and Range
    8  Northern Rocky Mountains
    9  Middle Rocky Mountains
   11  Southern Rocky Mountains
   12  Colorado Plateau
   13  Rocky Mountain Piedmont
   14  Great Plains
   15  Black Hills Uplift
   16  Upper Missouri Basin and Broken Lands

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Range

Almost ubiquitous, bracken is extremely common throughout Britain, and its range has increased dramatically during the 20th century. It occurs around the world, with the exception of the Arctic and Antarctic regions (4).
Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© Wildscreen

Source: ARKive

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

In the New World, Pteridium aquilinum in the strict sense occurs nearly throughout the United States and southern Canada, with extensions northward to about 55° N Latitude. The species is distributed southward through the mountains of Mexico into Central America as far as Honduras. It is also present in the Caribbean Islands and one subspecies is endemic to Hawaii. In the Old World, P. aquilinum occurs nearly throughout Europe (north to near the Arctic Circle) and Africa (excluding the Saharan portion), is present on a number of islands, including Madagascar, Réunion, the Mascarenes, Mauritius, and Macaronesia. Its Asian distribution extends eastward across Russia and south through China and Indochina into Malaysia. Farther south in both the Old and New Worlds, other species of Pteridium replace P. aquilinum, but there is distributional overlap between P. aquilinum and the other taxa, mainly in Latin America and portions of Asia.

Creative Commons Attribution 3.0 (CC BY 3.0)

George Yatskievych

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Physical Description

Morphology

Description

More info for the terms: cover, fern, fronds, litter, mutualism, perfect, rhizome, sori, stipe

The leaves or fronds of western bracken fern are normally from 1 to 10 feet
(3-30 dm) long including a stipe (leaf-stalk) that may be as long as 39
to 59 inches (10-15 dm) but is usually shorter than the leaf blade
[119].  The blades of the fronds are divided into pinnae, the bottom
pair of which are sometimes large enough to give the impression of a
three-part leaf.  Each pinna is in turn divided into pinnules.  Above
the first division of the stipe into a frond, it is called a rachis.  On
fertile fronds the spores are borne in sori beneath the outer margins of
the pinnules.  The sori are protected by the inrolled pinnule margins on
one side and a thin membrane called an indusium on the other [119].

Nectaries are found at the base of the pinnae during spring and early
summer [141,232].  The largest nectaries are found near the base of the
frond and the nectaries get progressively smaller going up the rachis
[141].  Ants are attracted by and feed on sugars produced by these
extra-floral nectaries [110,111,227].  It has been suggested but not
proven that an ant-plant mutualism may exist where the ants would attack
other insects feeding on the plants.  The ants do attack introduced
caterpillars and they tend an aphid species on western bracken fern in Arizona
[110,111,144,227].

The fronds are killed by frost.  In northern climates they are killed
each winter and new fronds grow in spring; in mild areas individual
fronds persist for 2 to 3 years before being replaced [195].  Dead
fronds form a mat of highly flammable litter that insulates the
below-ground rhizomes from frost when there is no snow cover.  This
litter also delays the rise in soil temperature and emergence of
frost-sensitive fronds in the spring [237].

Rhizomes are the main carbohydrate storage organs [48,243].  Rhizomes
also store water and are consistently around 87 percent water [211].
Rhizomes can be up to 1 inch (2.5 cm) in diameter [79] and branching is
alternate [236,238,239].  The rhizome system has two components.  The
long shoots form the main axis or stem of the plant [239].  They
elongate rapidly, have few lateral buds, do not produce fronds, and
store carbohydrates [48,236,243].  Short shoots, or leaf-bearing lateral
branches, may be closer to the soil surface [33].  They arise from the
long shoots, are slow growing, and produce annual fronds and many
dormant frond buds.  Transition shoots start from both short and long
shoots and may develop into either [48].  Thin, black, brittle roots
extend from the rhizome and may extend over 20 inches (50 cm) deeper
into the soil [211,238,239].  Endotrophic mycorrhizae have been found on
the roots of western bracken fern [41,126].

Fossil evidence suggests that western bracken fern has had at least 55 million
years to evolve and perfect antidisease and antiherbivore chemicals
[192].  It produces bitter tasting sesquiterpenes and tannins,
phytosterols that are closely related to the insect molting-hormone,
and cyanogenic glycosides that yield hydrogen cyanide (HCN) when
crushed.  It generates simple phenolic acids that reduce grazing, may
act as fungicides, and are implicated in western bracken fern's allelopathic
activity [42].  Severe disease outbreaks are very rare in western bracken fern
[126,192].

Most work describing western bracken fern has been done on var. aquilinum which
is closely related to varieties latiusculum, pseudocaudatum, and
pubescens [232].  Some differences between the varieties are noted below
[90,106,198,205,232,239].

P. a. var. latiusculum - Growth of the long rhizomes is relatively slow with
rates of 4 to 7 inches (10-17 cm) versus 10 to 35 inches (25-90 cm)
annually so it is less weedy than other varieties. The growing tip of the
rhizome has no hairs or a few whitish hairs.  The terminal segment of
the frond is not much longer than lateral segments; thus the frond
appears triangular or three-parted.  The only pubescence is along the
pinnule margins and midvein.

P. a. var. pseudocaudatum - The frond blade is usually completely glabrous and
rarely ternate.  The terminal segment of the frond is much longer than
the lateral segments and between six and fifteen times as long as broad.
The growing tip of the rhizome usually has a tuft of dark hairs.

P. a. var. pubescens - The frond blade is ovate-triangular but not ternate,
while the upper surface of the frond is frequently pubescent and the
lower surface is usually densely pubescent.  There is a tuft of dark
hairs on the growing tip of the rhizome.

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Description

Petioles scattered along creeping stems, 0.3--3.5 m, shallowly to deeply grooved adaxially, base not strongly distinct from stem. Blades broadly deltate, papery to leathery, sparsely to densely hairy abaxially, rarely glabrous. Pinnae often opposite to subopposite [alternate]; proximal pinnae often prolonged basiscopically, each proximal pinna nearly equal to distal part of leaf in size and dissection (except in var. caudata ). Segments alternate, numerous.
Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© Missouri Botanical Garden, 4344 Shaw Boulevard, St. Louis, MO, 63110 USA

Source: Missouri Botanical Garden

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Size

Physical Description

Medium- to large-sized ferns with a usually extensive system of long-creeping, branched, subterranean, hairy rhizomes, often forming large clonal colonies. Leaves mostly 0.5–1.5 m long, rarely to 2.5 m long, glabrous or variously hairy, long-petiolate, the petioles grooved along the upper side. Leaf blades 2 to 3 times pinnately compound and lobed, broadly deltate to deltate-triangular, ovate-triangular, or nearly pentagonal, the ultimate lobes or segments rounded to pointed at the tip, with strongly recurved, often pale margins, these irregular and usually sparsely to densely fringed along the edge, acting as a pseudoindusium to cover the developing sporangia (a true, outward-oriented indusium absent or vestigial). Sporangia in a continuous band along the leaf margins, hidden by the pseudoindusium until maturity. Spores 64 per sporangium, brown, nearly spherical (slightly tetrahedral), with a 3-branched tetrad scar (trilete), 23–40 μm in diameter, the outer surface irregularly granular. Source documents: Tryon (1941), Tryon and Tryon (1982), Kramer (1990), Tryon and Lugardon (1991), Jacobs and Peck (1993), Mickel and Smith (2004).
Creative Commons Attribution 3.0 (CC BY 3.0)

George Yatskievych

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Diagnostic Description

Synonym

Pteris aquilina Linnaeus, Sp. Pl. 2: 1075. 1753
Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© Missouri Botanical Garden, 4344 Shaw Boulevard, St. Louis, MO, 63110 USA

Source: Missouri Botanical Garden

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Formal Description

Large clonal ferns with medium- to large-size fronds. Rhizomes deeply seated, very long-creeping, repeatedly branched (some branches more elongate and not producing leaves, others shorter and frondiferous), densely pubescent with pale to dark brown, multicellular hairs; stele complex, described as two, concentric, highly corrugated solenosteles. Leaves (fronds) produced singly and remotely at rhizome nodes, (30–)50–150(–250) cm long. Petioles (stipes) not sharply distinct basally from the rhizome, (10–)25–100 cm long, erect or ascending, shallowly to deeply grooved adaxially, glabrous, glabrescent or hairy, the trichomes usually a mixture of short white hairs and minute gland-tipped, reddish hairs (these mostly in the groove); vascular bundles several, forming a U-shaped, horseshoe-shaped, or Ω-shaped pattern in cross-section. Laminae (blades) 20–150(–200) × 15–100 cm, broadly deltate to deltate-triangular, ovate-triangular, or nearly pentagonal, 2-pinnate-pinnatifid to 3-pinnate-pinnatifid (proximally), the pinnae mostly opposite to subopposite; proximal pinnae often prolonged basiscopically, the rachis and costae shallowly to deeply grooved with confluent, grooves, lacking prickles, pubescent similar to the petiole; small glandular patches (nectaries) present at bases of proximal and sometimes also distal pinnae; pinnules short to elongate, unlobed or few- to many-lobed, the lobes triangular to narrowly oblong or oblong-linear, rounded to pointed at the tips, the margins strongly reflexed; tissue chartaceous to somewhat coriaceous, abaxially glabrous to more commonly variously hairy (sometimes only on the costae and veins), adaxially glabrous or very sparsely hairy, except sometimes near the margins; veins mostly 1-forked, the branches often confluent marginally into a commissural vein. Sori an uninterrupted submarginal band along the commissural vein; excurrent true indusium absent or vestigial, a very slight ridge; pseudoindusium strongly developed, consisting of the recurved pinnule margin, this often white or pale, erose and often sparsely to densely long-ciliate. Sporangia with well-developed, triseriate stalks, the vertical annulus usually with a well-developed stomium. Spores 64 per sporangium, trilete, tetrahedral-globose, 23–32 μm in diameter, brown; perispore irregularly granular; exospore thin, undulate. Source documents: Tryon (1941), Tryon and Tryon (1982), Kramer (1990), Tryon and Lugardon (1991), Jacobs and Peck (1993), Mickel and Smith (2004).

Creative Commons Attribution 3.0 (CC BY 3.0)

George Yatskievych

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Ecology

Habitat

Habitat characteristics

More info for the terms: bog, cover, fern, ferns, fronds, heath, litter, rhizome

Western bracken fern grows on a variety of soils with the exception of heavily
waterlogged soils [23].  Its efficient stomatal control allows it to
succeed on sites that would be too dry for most ferns, and its
distribution does not normally seem limited by moisture [230,235].
Western bracken fern grows best on deep well-drained soils with good
water-holding capacity, and it may dominate other vegetation on such
sites [57,68].  Its productivity increases with increasing soil profile
development on Michigan entisols and spodosols [113].  In northern Idaho
the surface soil horizon under western bracken fern is an acidic, dark mineral
layer, while under interspersed conifer stands the surface soil horizon
is an acidic, light mineral layer [59].

Western bracken fern rhizomes are particularly effective at mobilizing
phosphorus from inorganic sources into an available form for plant use
[168].  Western bracken fern contributes to potassium cycling on sites and is
associated with high levels of potassium [28,157,175].  Fertilization of
cultured plants increases frond dry weight; using both nitrogen (N) and
phosphate (P) increases rhizome length, while using N, P, and potassium
(K) increases both rhizome length and rhizome dry weight [49].  Bracken
fern is characteristically found on soils with medium to very rich
nutrients [91,105,235].  In southeastern Alaska western bracken fern prefers a
pH of 5.0 to 6.0 [225].  It is absent from soils contaminated with zinc
[131].

In northern climates western bracken fern is frequently found on uplands and
side slopes, since it is susceptible to spring frost damage [47,150].
Fronds growing in the open or without litter cover are often killed as
crosiers by spring frost damage, since the soil warms earlier and growth
begins sooner [237].  The result is that fronds appear earlier in shaded
habitats [113,204].  Cultivated and shaded plants produce fewer, thinner
but larger fronds than open-grown plants [49].  A New York study found
that fronds growing in the shade were twice as likely as fronds growing
in the open to be cyanogenic [204].  That was also true in Great Britain
[43], however, a New Jersey study found no cyanogenic plants [226].
Shaded plants produce fewer spores than plants in full sun [189].

Elevation:  Elevational ranges in some western regions are [56,142,179]:

                        Minimum                  Maximum
                   feet      meters         feet      meters

New Mexico         8,000      2,438         9,500     2,896
California         sea level               10,000     3,048
Utah               5,500     1,676          8,000     2,438
Colorado           5,300     1,615         10,000     3,048
Wyoming            4,800     1,463          8,500     2,591
Montana            4,300     1,311          5,000     1,524

Var. pubescens is generally found in open forests, pastures, and on open
slopes; it is common following fire [189,232].  In the Pacific Northwest
western bracken fern is found along the coast on stabilized dune meadows and in
coastal prairies.  It is found in the forests of western Washington and
northwestern Oregon and it may be a dominant in grassy balds of the
Coast Mountains, subalpine meadows, and on avalanche tracks and
southerly slopes in the Cascades [57,78,169].  Western bracken fern increases
from west to east across the central Washington Cascades [53].  Within
the rain shadow area of the eastern slope of the Olympic Mountains,
western bracken fern is a dominant understory species in Oregon white oak
(Quercus garryana) savanna [50,228].  In the Columbia Basin of eastern
Oregon and Washington western bracken fern grows in riparian communities with
Douglas hawthorn (Crataegus douglasii) [78].  It is more frequent on
south-facing slopes in northern Idaho [175] and north-central Washington
where its cover is greater below 3,800 feet (1,150 m) than at higher
elevations [229].  It grows well on snow chutes in subalpine fir (Abies
lasiocarpa) habitat types in northwestern Montana [248].  In British
Columbia it grows best in areas with a humid climate, mild winters, and
a relatively long growing season [97].  In southeastern Alaska bracken
fern is found in the ecotone between forest and bog [180] or in muskegs
[225].  Western bracken fern is found in the coastal redwood region of
California and on flood plains and gentle slopes under the giant sequoia
(Sequoiadendron giganteum) in California's Sierra Nevada [108,235].  In
Arizona it is an understory species in deciduous, riparian forests [21].
In New Mexico and Arizona western bracken fern is found in the mountains under
blue spruce (Picea pungens) and Douglas-fir, in pinyon-juniper or Gambel
oak (Quercus gambelii) and ponderosa pine (Pinus ponderosa) woodlands,
and in grassy meadows [19,134,142,170,194].  Western bracken fern is found with
aspen in Colorado [15,121,122].

P. a. var. latiusculum:  In Wisconsin, northern Michigan, and probably
Minnesota, bracken-grasslands, doubtless initially caused by fire, are
found on soils ranging from loam to fine sand [47].  Some of these
bracken-grasslands occupy depressions with western bracken fern dominant on the
surrounding slopes.  Western bracken fern is also a common understory species in
Wisconsin oak (Quercus spp.) openings and barrens [47].  In New England
P. a. var. latiusculum and P. a. var. pseudocaudatum prefer dry woods, clearings,
fields, and thickets.  Western bracken fern is not found on limey soil [205].
In White Mountain forests it is most often found on dry areas of shallow
bedrock or outwash [147].

P. a. var. pseudocaudatum:  Southern western bracken fern is most common on
well-drained sandy soils under open stands of longleaf pine (Pinus
palustris), shortleaf pine (P. echinata), and mixtures of pine (Pinus
spp.) and oak [35,88,92,135].  It is also associated with pocosin [135].
In West Virginia western bracken fern was found on a high plateau growing among
other vegetation in a heath meadow with scattered small spruce [44].  On
the Alabama piedmont it is associated with upper slopes and ridges with
shallow soils [88].  Along the Atlantic Coastal Ridge of southern
Florida, western bracken fern is found on low hammocks and disturbed sites
[200].  Var. caudatum may also be found in this area on low hammocks and
disturbed sites [200].  On low hammocks western bracken fern is associated with
oaks and cabbage palmetto (Sabal palmetto) [200].  It is also found in
the margins of scrub vegetation where the sandy soil contains more clay
and silt and thus retains water better [178]

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Key Plant Community Associations

More info for the term: fern

Western bracken fern does not persist in forests beyond about 200 years [169].
It is a useful indicator of seral forest communities in western Oregon
[60].  In northwestern Colorado aspen (Populus tremuloides) communities,
western bracken fern indicates site deterioration [121].  Published
classification schemes listing western bracken fern as an indicator species or
as a dominant part of vegetation in community types (cts), habitat types
(hts), plant associations (pas), and ecosystem associations (eas) are
presented below:

Area               Classification           Authority

s CA               general veg pas, cts     Paysen and others 1980

CA: s Monterey     forest cts               Borchert and others 1988
County

nw CO: Routt NF    forest hts               Hoffman and Alexander 1980

w CO: White        forest hts               Hoffman and Alexander 1983
River NF

CO                 general veg, cts, pas    Baker 1984a

CO                 forest hts, cts          Alexander 1987

c ID               seral cts                Steele and Geier-Hayes 1989b

MI and WI          forest hts               Coffman and others 1980

s OR: Cascade Mtns forest pas               Atzet and McCrimmon 1990

nw OR              post-burn veg. cts       Bailey and Poulton 1968

OR, WA             general veg. cts         Franklin and Dyrness 1973

SD, WY: Black      forest and shrubland     Steinauer 1981
Hills NF           hts, cts

SD, WY: Black      forest and shrubland     Hoffman and Alexander 1987
Hills NF           hts

UT                 aspen cts                Mueggler and Campbell 1986

WA: Gifford        forest pas               Topik and others 1986
Pinchot N. F.

WA: Mt.Rainier NP  forest cts, hts          Moir and others 1976

WY                 forest hts               Alexander 1986

Intermountain      aspen cts                Mueggler 1988
Region: ID,NV,
UT,WY

Pacific            general veg. pas         Hall 1984
Northwest

Region 2: CO,NE,   general veg. pas         Johnston 1987
KS,SD,WY

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Habitat: Cover Types

More info on this topic.

This species is known to occur in association with the following cover types (as classified by the Society of American Foresters):

     1  Jack pine
     5  Balsam fir
    14  Northern pin oak
    15  Red pine
    16  Aspen
    17  Pin cherry
    18  Paper birch
    19  Gray birch - red maple
    20  White pine - northern red oak - red maple
    21  Eastern white pine
    22  White pine - hemlock
    23  Eastern hemlock
    25  Sugar maple - beech - yellow birch
    30  Red spruce - yellow birch
    31  Red spruce - sugar maple - beech
    32  Red spruce
    33  Red spruce - balsam fir
    35  Paper birch - red spruce - balsam fir
    42  Bur oak
    43  Bear oak
    44  Chestnut oak
    45  Pitch pine
    51  White pine - chestnut oak
    70  Longleaf pine
    71  Longleaf pine - scrub oak
    72  Southern scrub oak
    73  Southern redcedar
    74  Cabbage palmetto
    75  Shortleaf pine
    76  Shortleaf pine - oak
    80  Loblolly pine - shortleaf pine
    81  Loblolly pine
    82  Loblolly pine - hardwood
    83  Longleaf pine - slash pine
    98  Pond pine
   110  Black oak
   206  Engelmann spruce - subalpine fir
   210  Interior Douglas-fir
   211  White fir
   212  Western larch
   213  Grand fir
   215  Western white pine
   216  Blue spruce
   217  Aspen
   218  Lodgepole pine
   221  Red alder
   223  Sitka spruce
   224  Western hemlock
   225  Western hemlock - Sitka spruce
   226  Coastal true fir - hemlock
   227  Western redcedar - western hemlock
   229  Pacific Douglas-fir
   230  Douglas-fir - western hemlock
   232  Redwood
   233  Oregon white oak
   234  Douglas-fir - tanoak - Pacific madrone
   236  Bur oak
   237  Interior ponderosa pine
   243  Sierra Nevada mixed conifer
   244  Pacific ponderosa pine - Douglas-fir
   245  Pacific ponderosa pine
   249  Canyon live oak
   250  Blue oak - Digger pine
   255  California coast live oak

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Habitat: Plant Associations

More info on this topic.

This species is known to occur in association with the following plant community types (as classified by Küchler 1964):

   K001  Spruce - cedar - hemlock forest
   K002  Cedar - hemlock - Douglas-fir forest
   K003  Silver fir - Douglas-fir forest
   K005  Mixed conifer forest
   K006  Redwood forest
   K007  Red fir forest
   K008  Lodgepole pine - subalpine forest
   K009  Pine - cypress forest
   K011  Western ponderosa forest
   K012  Douglas-fir forest
   K013  Cedar - hemlock - pine forest
   K014  Grand fir - Douglas-fir forest
   K015  Western spruce - fir forest
   K017  Black Hills pine forest
   K018  Pine - Douglas-fir forest
   K019  Arizona pine forest
   K020  Spruce - fir - Douglas-fir forest
   K021  Southwestern spruce - fir forest
   K023  Juniper - pinyon woodland
   K025  Alder - ash forest
   K026  Oregon oakwoods
   K028  Mosaic of K002 and K026
   K029  California mixed evergreen forest
   K030  California oakwoods
   K033  Chaparral
   K047  Fescue - oatgrass
   K093  Great Lakes spruce - fir forest
   K095  Great Lakes pine forest
   K096  Northeastern spruce - fir forest
   K100  Oak - hickory forest
   K106  Northern hardwoods
   K107  Northern hardwoods - fir forest
   K108  Northern hardwoods - spruce forest
   K110  Northeastern oak -pine forest
   K111  Oak - hickory - pine forest
   K112  Southern mixed forest
   K114  Pocosin
   K115  Sand pine scrub
   K116  Subtropical pine forest

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Habitat: Ecosystem

More info on this topic.

This species is known to occur in the following ecosystem types (as named by the U.S. Forest Service in their Forest and Range Ecosystem [FRES] Type classification):

   FRES10  White - red - jack pine
   FRES11  Spruce - fir
   FRES12  Longleaf - slash pine
   FRES13  Loblolly - shortleaf pine
   FRES14  Oak - pine
   FRES15  Oak - hickory
   FRES18  Maple - beech - birch
   FRES19  Aspen - birch
   FRES20  Douglas-fir
   FRES21  Ponderosa pine
   FRES22  Western white pine
   FRES23  Fir - spruce
   FRES24  Hemlock - Sitka spruce
   FRES25  Larch
   FRES26  Lodgepole pine
   FRES27  Redwood
   FRES28  Western hardwoods
   FRES34  Chaparral - mountain shrub
   FRES36  Mountain grasslands

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

This fern is found in moorland, hill pasture and a variety of other habitats with acidic soils. It particularly thrives on deep loams and sands, but is rare on alkaline soil; it has been found at heights of up to 585 m, but probably occurs higher than this in some areas (3).
Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© Wildscreen

Source: ARKive

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Pteridium aquilinum is a terrestrial species that occurs in a wide variety of habitats, ranging from sand dunes to peatlands and open meadows to forests. It is especially aggressive in disturbed or successional habitats, including those prone to periodic disturbance by natural processes such as fires. Human-mediated perturbations such as grazing and timber removal tend to stimulate its growth and spread. It occurs from sea level to ca. 3300 m in soils derived from a wide variety of substrates and with various pH levels.

Creative Commons Attribution 3.0 (CC BY 3.0)

George Yatskievych

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Associations

In Great Britain and/or Ireland:
Plant / associate
fruitbody of Amanita fulva is associated with Pteridium aquilinum

Plant / associate
fruitbody of Ampulloclitocybe clavipes is associated with Pteridium aquilinum

Foodplant / open feeder
larva of Aneugmenus coronatus grazes on frond of Pteridium aquilinum
Other: major host/prey

Plant / associate
Aneugmenus f is associated with Pteridium aquilinum
Other: major host/prey

Plant / associate
larva of Aneugmenus padi is associated with frond of Pteridium aquilinum
Other: major host/prey

Plant / associate
Aneugmenus temporalis is associated with Pteridium aquilinum
Other: major host/prey

Foodplant / saprobe
colony of Arthrinium dematiaceous anamorph of Arthrinium phaeospermum is saprobic on dead leaf of Pteridium aquilinum
Remarks: season: esp. 7-8

Foodplant / saprobe
solitary or few, epiphyllous, immersed then erumpent to superficial pycnidium of Ascochyta coelomycetous anamorph of Ascochyta pteridis is saprobic on dead petiolule of Pteridium aquilinum
Remarks: season: 7

Plant / epiphyte
fruitbody of Athelia pyriformis grows on dead frond of Pteridium aquilinum

Foodplant / saprobe
fruitbody of Athelopsis lembospora is saprobic on decayed debris of Pteridium aquilinum

Foodplant / saprobe
fruitbody of Basidiodendron cremeum is saprobic on dead, standing rachis of Pteridium aquilinum

Foodplant / saprobe
fruitbody of Basidiodendron radians is saprobic on debris of Pteridium aquilinum

Foodplant / saprobe
fruitbody of Basidiodendron spinosum is saprobic on decayed debris of Pteridium aquilinum

Foodplant / saprobe
fruitbody of Boidinia furfuracea is saprobic on decayed debris of Pteridium aquilinum
Other: minor host/prey

Foodplant / saprobe
fruitbody of Botryobasidium danicum is saprobic on debris of Pteridium aquilinum

Foodplant / saprobe
fruitbody of Botryobasidium pruinatum is saprobic on debris of Pteridium aquilinum

Foodplant / parasite
effuse colony of Botryosporium anamorph of Botryosporium pulchrum parasitises live Pteridium aquilinum
Remarks: season: 5-11

Foodplant / saprobe
linearly arranged, subepidermal then epidermis turns brown and opens by a slit conidioma of Camarographium coelomycetous anamorph of Camarographium stephensii is saprobic on dead petiole of Pteridium aquilinum
Remarks: season: 5-7

Foodplant / feeds on
basidiome of Ceratobasidium anceps feeds on live frond of Pteridium aquilinum

Foodplant / saprobe
effuse colony of Chalara dematiaceous anamorph of Chalara fungorum is saprobic on dead Pteridium aquilinum

Foodplant / saprobe
effuse colony of Chalara dematiaceous anamorph of Chalara parvispora is saprobic on dead frond of Pteridium aquilinum
Remarks: season: 5

Foodplant / saprobe
effused Chalara dematiaceous anamorph of Chalara pteridina is saprobic on dead petiole of Pteridium aquilinum
Remarks: season: 4-11

Foodplant / saprobe
erumpent pycnidium of Coniothyrium coelomycetous anamorph of Coniothyrium pteridis is saprobic on dead pinna of Pteridium aquilinum

Foodplant / saprobe
fruitbody of Crepidotus luteolus is saprobic on dead stem of Pteridium aquilinum

Foodplant / saprobe
fruitbody of Cristinia helvetica is saprobic on decayed debris of Pteridium aquilinum

Foodplant / saprobe
short-stalked apothecium of Crocicreas cyathoideum var. cyathoideum is saprobic on dead stem of Pteridium aquilinum
Remarks: season: 3-10

Foodplant / saprobe
short-stalked apothecium of Crocicreas cyathoideum var. pteridicola is saprobic on dead stem of Pteridium aquilinum
Remarks: season: 4-7

Plant / resting place / on
adult of Cryptocephalus bipunctatus may be found on near ant nest Pteridium aquilinum
Remarks: season: 4-late 8

Foodplant / saprobe
conidioma of Cryptomycella coelomycetous anamorph of Cryptomycina pteridis is saprobic on dead frond of Pteridium aquilinum

Foodplant / pathogen
Dactylium dendroides ssp. leptosporum infects and damages diseased frond of Pteridium aquilinum

Foodplant / gall
larva of Dasineura filicina causes gall of frond of Pteridium aquilinum

Foodplant / saprobe
erumpent conidioma of Phomopsis coelomycetous anamorph of Diaporthopsis pantherina is saprobic on dead petiole of Pteridium aquilinum
Remarks: season: 2+

Foodplant / saprobe
epiphyllous, densely gregarious pseudothecium of Didymella lophospora is saprobic on dead frond of Pteridium aquilinum
Remarks: season: 7

Foodplant / saprobe
immersed, raising the epidermis pseudothecium of Didymella prominula is saprobic on dead stem of Pteridium aquilinum
Remarks: season: 6

Foodplant / saprobe
fruitbody of Endoperplexa enodulosa is saprobic on decayed debris of Pteridium aquilinum

Foodplant / saprobe
Exochalara anamorph of Exochalara longissima is saprobic on Pteridium aquilinum

Foodplant / debris feeder
larva of Fannia monilis feeds on rotten Pteridium aquilinum

Foodplant / saprobe
fruitbody of Galerina ampullaceocystis is saprobic on debris of Pteridium aquilinum

Foodplant / saprobe
fruitbody of Galerina cinctula is saprobic on debris of Pteridium aquilinum

Foodplant / saprobe
fruitbody of Galerina marginata is saprobic on debris of Pteridium aquilinum

Plant / associate
fruitbody of Geastrum triplex is associated with Pteridium aquilinum
Other: minor host/prey

Foodplant / saprobe
fruitbody of Hemimycena delectabilis is saprobic on decayed debris of Pteridium aquilinum

Plant / associate
fruitbody of Hygrocybe laeta var. laeta is associated with live Pteridium aquilinum

Foodplant / saprobe
fruitbody of Hyphodontia detritica is saprobic on dead, decayed frond of Pteridium aquilinum
Other: minor host/prey

Foodplant / saprobe
fruitbody of Hyphodontia griseliniae is saprobic on dead, decayed debris of Pteridium aquilinum

Foodplant / saprobe
fruitbody of Hypochnicium geogenium is saprobic on dead, fallen, decayed debris of Pteridium aquilinum
Other: minor host/prey

Foodplant / saprobe
apothecium of Lachnum pteridialis is saprobic on dead frond of Pteridium aquilinum
Remarks: season: 10

Foodplant / saprobe
apothecium of Lachnum pteridis is saprobic on dead stem of Pteridium aquilinum
Remarks: season: 8-5

Foodplant / saprobe
long stalked apothecium of Lachnum virgineum is saprobic on dead frond of Pteridium aquilinum
Remarks: season: 2-10

Plant / associate
fruitbody of Lactarius camphoratus is associated with Pteridium aquilinum

Foodplant / saprobe
Pycnothyrium anamorph of Leptopeltis litigiosa is saprobic on dead petiole of Pteridium aquilinum
Remarks: season: 6-9

Foodplant / saprobe
subcuticular, usually confluent thyriothecium of Leptopeltis pteridis is saprobic on dead frond (vein) of Pteridium aquilinum

Foodplant / saprobe
fruitbody of Leptosporomyces galzinii is saprobic on dead, decayed debris of Pteridium aquilinum
Other: unusual host/prey

Foodplant / saprobe
fruitbody of Leucoagaricus georginae is saprobic on dead, decayed debris of Pteridium aquilinum
Other: unusual host/prey

Foodplant / saprobe
thyriothecium of Lichenopeltella nigroannulata is saprobic on dead frond of Pteridium aquilinum

Foodplant / saprobe
fruitbody of Lindtneria trachyspora is saprobic on dead stem of Pteridium aquilinum

Foodplant / saprobe
fruitbody of Litschauerella clematidis is saprobic on dead stem of Pteridium aquilinum
Other: unusual host/prey

Foodplant / saprobe
fruitbody of Luellia cystidiata is saprobic on dead, decayed debris of Pteridium aquilinum
Other: unusual host/prey

Foodplant / saprobe
fruitbody of Luellia recondita is saprobic on dead stem of Pteridium aquilinum
Other: major host/prey

Foodplant / saprobe
fruitbody of Marasmiellus vaillantii is saprobic on dead stem of Pteridium aquilinum

Foodplant / pathogen
fruitbody of Marasmius undatus infects and damages dying rhizome of Pteridium aquilinum
Other: sole host/prey

Foodplant / saprobe
immersed, exposed by irregualr splitting of epidermis apothecium of Mellitiosporium pteridinum is saprobic on dead stem of Pteridium aquilinum
Remarks: season: 3-4

Plant / associate
fruitbody of Micromphale impudicum is associated with Pteridium aquilinum

Foodplant / saprobe
apothecium of Micropodia pteridina is saprobic on dead stem of Pteridium aquilinum
Remarks: season: 3-9

Foodplant / saprobe
hypophyllous, short-stalked apothecium of Microscypha grisella is saprobic on damp, dead frond of Pteridium aquilinum
Remarks: season: 5-8

Foodplant / saprobe
apothecium of Mollisia pteridis sensu Gillet is saprobic on locally blackened, dead, standing stem of Pteridium aquilinum
Remarks: season: 6-7

Foodplant / sap sucker
adult of Monalocoris filicis sucks sap of sporangia of Pteridium aquilinum
Other: major host/prey

Foodplant / gall
larva of Monochroa cytisella causes gall of stem, side-shoot of Pteridium aquilinum

Foodplant / saprobe
ascocarp of Monographos fuckelii is saprobic on dead petiole of Pteridium aquilinum
Remarks: season: 7-8

Foodplant / saprobe
fruitbody of Mycena amicta is saprobic on dead, fallen, decayed litter of Pteridium aquilinum
Other: unusual host/prey

Foodplant / saprobe
fruitbody of Mycena arcangeliana is saprobic on dead, decayed stem of Pteridium aquilinum
Other: unusual host/prey

Foodplant / saprobe
fruitbody of Mycena clavularis is saprobic on dead, decaying debris of Pteridium aquilinum
Other: unusual host/prey

Foodplant / saprobe
fruitbody of Mycena epipterygia is saprobic on dead, decayed debris of Pteridium aquilinum

Foodplant / saprobe
fruitbody of Mycena pterigena is saprobic on dead, decayed debris of Pteridium aquilinum

Foodplant / saprobe
toadstool of Mycena vulgaris is saprobic on dead, fallen, decaying debris of Pteridium aquilinum
Other: minor host/prey

Foodplant / parasite
Mycosphaerella aspidii parasitises Pteridium aquilinum

Foodplant / saprobe
epiphyllous, often grouped, immersed pseudothecium of Mycosphaerella pteridis is saprobic on dead frond of Pteridium aquilinum

Foodplant / saprobe
fruitbody of Oliveonia pauxilla is saprobic on dead, decayed debris of Pteridium aquilinum

Foodplant / saprobe
fruitbody of Phanerochaete martelliana is saprobic on dead stem of Pteridium aquilinum

Foodplant / saprobe
hypophyllous apothecium of Phialina flaveola is saprobic on damp, dead frond of Pteridium aquilinum
Remarks: season: 6-7

Foodplant / saprobe
fruitbody of Phlebiella christiansenii is saprobic on debris of Pteridium aquilinum

Foodplant / saprobe
fruitbody of Phlebiella fibrillosa is saprobic on dead, decayed debris of Pteridium aquilinum

Foodplant / saprobe
fruitbody of Phlebiella filicina is saprobic on dead, decayed debris of Pteridium aquilinum
Other: major host/prey

Foodplant / saprobe
deeply immersed perithecium of Phomatospora endopteris is saprobic on dead frond of Pteridium aquilinum

Foodplant / saprobe
gregarious, lirelliform pycnidium of Phomopsis coelomycetous anamorph of Phomopsis aquilina is saprobic on dead rhachis of Pteridium aquilinum
Remarks: season: 8-9

Plant / resting place / on
puparium of Phytoliriomyza hilarella may be found on frond of Pteridium aquilinum

Foodplant / feeds on
Procas granulicollis feeds on Pteridium aquilinum
Remarks: Other: uncertain

Foodplant / saprobe
short-stalked apothecium of Psilachnum chrysostigmum is saprobic on dead frond of Pteridium aquilinum
Remarks: season: 10-5

Foodplant / saprobe
sessile apothecium of Psilachnum pteridigenum is saprobic on dead frond of Pteridium aquilinum
Remarks: season: 5-9

Plant / associate
fruitbody of Ramariopsis kunzei is associated with debris of Pteridium aquilinum

Foodplant / saprobe
subepidermal, often confluent stroma of Rhopographus filicinus is saprobic on dead petiole of Pteridium aquilinum
Remarks: season: 2-6

Foodplant / saprobe
subepidermal, splitting the epidermis stroma of Scirrhia aspidiorum is saprobic on dead petiole of Pteridium aquilinum
Remarks: season: 5-7

Plant / associate
fruitbody of Scleroderma cepa is associated with Pteridium aquilinum
Other: unusual host/prey

Foodplant / saprobe
fruitbody of Scotomyces subviolaceus is saprobic on dead, decayed debris of Pteridium aquilinum

Foodplant / saprobe
fruitbody of Sistotrema oblongisporum is saprobic on dead, decayed debris of Pteridium aquilinum

Foodplant / saprobe
Sphaerothyrium coelomycetous anamorph of Sphaerothyrium filicinium is saprobic on dead Pteridium aquilinum

Foodplant / saprobe
effuse colony of Stachylidium dematiaceous anamorph of Stachylidium bicolor is saprobic on dead stem of Pteridium aquilinum

Foodplant / open feeder
larva of Strombocerus delicatulus grazes on frond of Pteridium aquilinum
Other: major host/prey

Foodplant / open feeder
larva of Strongylogaster filicis grazes on frond of Pteridium aquilinum
Other: major host/prey

Foodplant / open feeder
larva of Strongylogaster lineata grazes on frond of Pteridium aquilinum
Other: major host/prey

Foodplant / open feeder
larva of Strongylogaster macula grazes on frond of Pteridium aquilinum
Other: major host/prey

Foodplant / open feeder
larva of Strongylogaster xanthocera grazes on frond of Pteridium aquilinum
Other: sole host/prey

Foodplant / internal feeder
larva of Syagrius intrudens feeds within rootstock of Pteridium aquilinum

Foodplant / open feeder
nocturnal larva of Tenthredo colon grazes on frond of Pteridium aquilinum

Foodplant / open feeder
nocturnal larva of Tenthredo ferruginea grazes on frond of Pteridium aquilinum

Foodplant / open feeder
nocturnal larva of Tenthredo livida grazes on frond of Pteridium aquilinum

Plant / associate
fruitbody of Tephrocybe confusa is associated with Pteridium aquilinum

Plant / resting place / on
fruitbody of Tomentella radiosa may be found on dead, decayed debris of Pteridium aquilinum

Foodplant / saprobe
fruitbody of Trechispora stellulata is saprobic on dead, decayed stem of Pteridium aquilinum

Foodplant / saprobe
fruitbody of Tricholomopsis rutilans is saprobic on dead, decayed debris of Pteridium aquilinum
Other: unusual host/prey

Foodplant / saprobe
Tubulicrinis regificus is saprobic on dead stem of Pteridium aquilinum

Foodplant / saprobe
basidiome of Tulasnella brinkmannii is saprobic on dead stem of Pteridium aquilinum

Foodplant / saprobe
fruitbody of Typhula quisquiliaris is saprobic on dead, decayed stem of Pteridium aquilinum
Other: major host/prey

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Population Biology

Frequency

Locally abundant
Creative Commons Attribution Non Commercial 3.0 (CC BY-NC 3.0)

© Mark Hyde, Bart Wursten and Petra Ballings

Source: Flora of Zimbabwe

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Frequency

Locally abundant
Creative Commons Attribution Non Commercial 3.0 (CC BY-NC 3.0)

© Mark Hyde, Bart Wursten and Petra Ballings

Source: Flora of Zimbabwe

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

General Ecology

Fire Management Considerations

More info for the terms: cover, fern, fronds, fuel, fuel loading, prescribed fire, rhizome

Fire can facilitate the spread of western bracken fern [23,70].  The least
favorable time for prescribed burning is just after the new fronds have
fully expanded and starch reserves in the rhizomes are at their lowest
level [31,136,154, 155,160,196,218,243].  A fire at this time can reduce
western bracken fern for up to 2 years [195].  Although more fronds may be
produced, total frond weight and rhizome starch are greatly reduced
[196].  If a prescribed fire at this time is followed with a second
treatment, the rhizome system will be further depleted and fewer dormant
buds may sprout.  Since there are more fronds, a herbicide would have
more entry points to the rhizome system [196].

Fine fuel loading in areas dominated by western bracken fern can be quite high
[2,128,95,162,234].  Brown and Marsden [1976] have developed a formula
to estimate fuel loading using the relationship between fuel loading and
the ground cover and height of western bracken fern.

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Broad-scale Impacts of Plant Response to Fire

More info for the terms: cover, fern, fire severity, frequency, hardwood, prescribed fire, rhizome, severity, wildfire

All varieties of western bracken fern are well adapted to fire, but there are
differences in rhizome growth rates and their response to disturbance
[73,189,192,232].  Among the most important North American varieties,
P. a. var. latiusculum and P. a. var. pseudocaudatum are slower growing and
considered less weedy [232,239].  This along with factors such as
season, fire severity and intensity, and site characteristics may
explain some reported differences in response following fire.

P. a. var. pubescens:  Western bracken fern invades recently logged and burned areas
in the Oregon Cascades, sometimes in the first year and sometimes after
several years [100,173,214,246].  Repeated fires or burns that are
delayed following logging favor a rapid increase in cover and
encroachment of western bracken fern [82].  Along the Pacific coast western bracken fern
invades recent burns by windborne spores and also spreads from its
buried rhizome [128].  After spring fires in northern Idaho, bracken
fern production dropped somewhat in the first year and then increased in
the second and third years [148].  Western bracken fern increased following
single or multiple broadcast fires in northern Idaho [175].  After
logging or fire in Arizona ponderosa pine communities, western bracken fern may
cover up to 30 percent of the area for 10 or more years [27,187,188].

P. a. var. latiusculum:  It is generally agreed that the bracken-grasslands
[47] of Wisconsin originated as a result of fires [233].  However,
following early spring prescribed fires in these areas, western bracken fern's
relative frequency decreased the year after the fire [233].  In New York
oak woods, Swan [223] also found a decrease in frequency following
spring fires; however, western bracken fern increased in abundance at the same
time.  He suggested that existing clumps became denser.  Studies in
Great Lakes area jack pine forests show that western bracken fern sprouts, and
its cover and biomass usually remain fairly stable, either decreasing or
increasing slightly after burning [4,5,163,184,185].  In red and white
pine (Pinus resinosa and P. strobus) forests of Ontario, western bracken fern
decreased slightly after logging without burning but increased strongly
following logging and early summer burning [207,208].  Increased bracken
fern following a spring fire in a Pennsylvania scrub oak community was
attributable to both spore germination and rhizome sprouts [99].  In
northeastern hardwood stands western bracken fern sprouts rapidly following fire
and repeated fires may lead to its domination [152,209].  In oak-pine
forests of the Pine Barrens region of New Jersey, western bracken fern thrives
following severe fires [17,161].  It increases moderately in canopy gaps
in these forests following surface fires.

P. a. var. pseudocaudatum:  Western bracken fern is well adapted to fires and
increases its cover greatly when it is burned repeatedly in longleaf
pine and slash pine forests [138].  After two successive wintertime
prescribed underburns, western bracken fern increased its frequency from 16.7 to
20.6 percent and doubled its biomass in a Florida slash and longleaf
pine forest [171].  Western bracken fern is common following fire in the
pocosins of the Southern Coastal Plain [32].  Its regrowth following a
severe July wildfire in mixed pine (Pinus taeda or P. palustris) and oak
(Quercus virginiana and Q. laurifolia) was vigorous, and cover increased
each of the first 2 years [51].  In South Carolina loblolly pine stands
that have been repeatedly burned for 20 years, western bracken fern is found
only in areas burned during the summer and not on winter-burned areas
[152].  In the southeastern United States, prescribed fire has been used
extensively since 1960, favoring western bracken fern and allowing it to
dominate other understory species, including wiregrass (Aristida
stricta) which had been prominent [224].

The following Research Project Summaries
provide information on prescribed

fire use and postfire response of plant
community species, including western

bracken fern, that was not available when this
species review was originally

written:

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Plant Response to Fire

More info for the terms: competition, fern, gametophyte

Western bracken fern is well known as a postfire colonizer in western
coniferous forests and eastern pine and oak forests [17,156].  Fire
benefits western bracken fern by removing its competition while it sprouts
profusely from surviving rhizomes [97,192,229].  New sprouts are more
vigorous following fire, and western bracken fern becomes more fertile,
producing far more spores than it does in the shade [191].  Sprouting is
slower following summer burns than following spring and fall burns [76].

Western bracken fern spores germinate well on alkaline soils, allowing them to
establish in the basic conditions created by fire [85,191,192].  In a
moist tropical habitat in Costa Rica, western bracken fern gametophyte plants
were observed covering the burned surface of bare ground and ash, but no
plants were observed on unburned sites [85].  In North America
establishment of new plants from spores on recently burned areas appears
to be most likely in the moister conditions near either coastline
[99,128].

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Immediate Effect of Fire

More info for the terms: fern, fronds

Western bracken fern is a survivor [220,221].  The fronds of plants are
generally killed by fire, but some rhizomes survive [1,74,75].  The
rhizomes are sensitive to elevated temperatures.  Except in the spring,
sprouting is less vigorous when rhizomes are exposed to temperatures of
113 degrees F (45 degrees C), and they die when exposed to temperatures
above 131 degrees F (55 degrees C) [74].  During fires the rhizome
system is insulated by mineral soil [74,75].  Depth of the main rhizome
system is normally between 3.5 and 12 inches (8 and 30 cm); short
rhizomes may be within 1.5 inches (3.7 cm) of the surface and some
rhizomes may be as deep as 39.4 inches (1 m) [37,68,74,75,79,87,113].

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Post-fire Regeneration

   survivor species; on-site surviving rhizomes
   off-site colonizer; spores carried by wind; postfire years one and two

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Fire Ecology

More info for the terms: competition, fern, fronds, fuel

Western bracken fern is considered a fire-adapted species throughout the world
[192].  It is not only well adapted to fire, it promotes fire by
producing a highly flammable layer of dried fronds every fall
[2,79,128,234].  In the Pacific Northwest western bracken fern fronds grow to 6
feet, resulting in several tons of flashy fuel per acre [162] and
western bracken fern adds to the high fuel loads in northern Idaho brushfields
[95].  Repeated fires favor western bracken fern [2,127,128,206].

Most sources agree that western bracken fern's primary fire adaptation is its
deeply buried rhizomes which sprout vigorously following fires before
most competing vegetation is established [6,30,192,209,220,221,224].
Western bracken fern's windborne spores may disperse over long distances.  Fire
removes competition and creates the alkaline soil conditions suitable
for its establishment from spores [192].

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Successional Status

More info on this topic.

More info for the terms: competition, cover, eruption, fern, rhizome, shrubs, succession

Western bracken fern is basically a shade-intolerant pioneer and seral species
that is sufficiently shade tolerant to survive in light-spots in
old-growth forests [127,192,216].  A study in southwestern Oregon
suggested that western bracken fern is an indicator of light intensity.  In this
study western bracken fern cover was 75 percent at 60 to 100 percent of full
sunlight, and dropped to 50 percent between 25 and 60 percent of full
sunlight.  When light intensity was under 25 percent of full sunlight,
western bracken fern cover was less than 5 percent [61].

The light, windborne spores of western bracken fern allow it to colonize newly
vacant areas.  Western bracken fern has been documented as a pioneer on sterile,
cooled lava slopes [190].  After disturbance in western Washington and
northwestern Oregon forests, western bracken fern often invades sites where it
was not previously present [78,100].  It enters the dry meadow stage of
succession on coastal sand dunes of the Pacific Northwest and was an
early seral species following the eruption of Mount St. Helens where
some plants were observed originating from rhizome fragments
[78,101,164].

In areas unaffected by coastal moisture western bracken fern rarely establishes
from spores [68].  However, solitary plants may expand from rhizomes
following disturbance [220,221].  These plants may depend upon canopy
level removal or openings for establishment of a system of clonal
ramets.  Under a canopy of oak and pine in the New Jersey pine barrens,
western bracken fern distribution resembles that of sexually reproducing herbs
rather than that of clones [161].

In western forests very small amounts of western bracken fern persist under a
canopy for at least 200 to 400 years [94,133,169].  Following
disturbance, western bracken fern is a common seral species that may be dominant
in coastal forests from Oregon to Southern Alaska and in New England
[50,94,114,133].  In the Pacific Northwest annuals may be followed
closely by western bracken fern and other perennials [45,203].  It is seral in
Oregon's interior valleys [89], in California coastal redwoods, and in
valley oak (Quercus lobata), blue oak (Q. douglasii), and digger pine
(Pinus sabiniana) savannas [93,249].  It follows disturbance in grand
fir and cedar hemlock forests of the northern Rocky Mountains [153].  It
occurs in seral brush fields in northern Idaho and southwestern Oregon
[95,109].  In contrast, a study in white fir (Abies concolor) forests of
the Sierra Nevada found western bracken fern predominantly in mature or late
seral stands with low light intensities [36].  Authors of a New Jersey
study with similar results suggested that western bracken fern distribution in
their area was spotty and showed no real preference for low light [24].

In Southern longleaf pine plantations western bracken fern is associated with
disturbance following thinning operations but is absent from patch or
clearcut areas [245].  Following fire in a Pennsylvania scrub oak
(Quercus ilicifolia) community, western bracken fern increased rapidly
immediately after burning but declined sharply after the first year due
to competition from blueberry (Vaccinium spp.) and huckleberry
(Gaylussacia spp.) [99].

Where western bracken fern invades grasslands and low shrublands, it may exhibit
a cyclic succession.  If undisturbed, the dense western bracken fern cover
gradually deteriorates into sparse western bracken fern with grass and shrubs.
Eventually dense western bracken fern may reinvade [159,238].

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Regeneration Processes

More info for the terms: bisexual, fern, ferns, fronds, gametophyte, genotype, rhizome

Most regeneration in western bracken fern is vegetative.  Many investigators
have searched for young plants growing from spores [186, Stickney 1989,
personal communication], but few have found them.  However, spores do
germinate and grow readily in culture [7,33,37,40].

Young western bracken fern plants can produce spores by the end of the second
growing season in cultivation but normally do not produce spores until
the third or fourth growing season [40,97].  A single, fertile frond can
produce 300,000,000 spores annually [38,40].  Spore production varies
from year to year depending on plant age, frond development, weather,
and light exposure [40].  Production decreases with increasing shade
[40,189].  The wind-borne spores are extremely small.  Dry spores are
very resistant to extreme physical conditions, although the germination
of western bracken fern spores declines from 95 to 96 percent to around 30 to 35
percent after 3 years storage [190].  The spores germinate without any
dormancy requirement.  Under favorable conditions, young plants could be
found 6 to 7 weeks after the spores are shed [37,40].  Under normal
conditions the spores may not germinate until the spring after they are
shed [33,38].

Sufficient moisture and shelter from wind are important factors in fern
spore germination [167].  Western bracken fern spore germination appears to
require soil sterilized by fire [37,186].  On unsterilized soils spores
may germinate, but the new plants are quickly overwhelmed by other
growth [37].  Temperatures between 59 and 86 degrees F (15-30 degrees C)
are generally best for germination, although western bracken fern is capable of
germination at 33 to 36 degrees F (1-2 degrees C).  A pH range of 5.5 to
7.5 is optimal for germination [38,167].  Germination of western bracken fern is
indifferent to light quality; it is one of the few ferns that can
germinate in the dark [189,240].  Despite limitations on spore
germination, genotype analysis in the Northeast indicates that many
stands of western bracken fern represent multiple establishment of individuals
from spores [96,250].

When spores germinate, they produce bisexual, gamete-bearing plants
about 0.25 inch (0.6 cm) in diameter and one cell thick.  These tiny
plants (gametophytes or prothalli) have no vascular system and require
very moist conditions to survive.  The young spore-bearing plant
(sometimes called a sporling) which develops from the fertilized egg is
initially dependent on the gametophyte until it develops its first leaf
and roots.  The first fronds are simple and lobed.  They develop into
thin, delicate fronds divided into lobed pinnae.  They do not look like
adult plants and are frequently not recognized as western bracken fern [37,189].
Cultivated plants of var. aquilinum begin to resemble adult western bracken fern
after 18 weeks.  The rhizomes begin to develop after there are a number
(up to 10) of fronds and a well-developed root system or in the
fifteenth week of growth under optimal conditions.  In the first year
rhizomes may grow to 86 inches (217 cm) long [20].  By the end of a
second year the rhizome system may exceed 6 feet (18 dm) in diameter
[20,37].

Western bracken fern's aggressive rhizome system gives it the ability to
reproduce vegetatively and reduces the plant's dependence on water for
reproduction [42].  The rhizomatous clones can be hundreds of years old,
and some clones alive today may be over 1,000 years old [186,192,250].
Rhizomes have a high proportion of dormant buds [236].  When disturbed
or broken off, all portions of the rhizome may sprout, and plants
growing from small rhizome fragments revert temporarily to a juvenile
morphology [48, 192].  A recent study of western bracken fern genotypes using
isozyme patterns found individual clones in New England were up to 400
feet (120 m) in diameter, and clones often intermingled in an area
[250].

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Growth Form (according to Raunkiær Life-form classification)

More info on this topic.

More info for the term: geophyte

   Undisturbed State:  Cryptophyte (geophyte)
   Burned or Clipped State:  Cryptophyte (geophyte)

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Life Form

More info for the terms: fern, fern ally

Fern or Fern Ally

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Ecological Determinants/Niche

Pteridium aquilinum is especially aggressive in disturbed or successional habitats, including those prone to periodic disturbance by natural processes such as fires.

Creative Commons Attribution 3.0 (CC BY 3.0)

George Yatskievych

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Life History and Behavior

Cyclicity

Phenology

More info on this topic.

More info for the terms: fern, fronds

In North America, fronds usually begin to emerge between March and early
May.  Frost-killed fronds are replaced through mid-July [33].  In a
northern Idaho study, western bracken fern first appeared in early May and
continued growth through mid-July.  The fronds began to change color by
mid-August, probably because of limited soil moisture [58].  Spore
maturation and dispersal begins at the base of the frond and proceeds up
to the tip resulting in an extended period of spore dispersal [40].  In
New England and the Carolinas, western bracken fern produces spores from early
July to late September [198,205].  Spore release in Michigan is between
the first of June and mid-August [115] and from July to September on the
Great Plains [90].  In Canada sporulating begins as early as June 24 in
Ontario, June 29 in Quebec, July 16 in Nova Scotia, July 22 in British
Columbia, July 29 in New Brunswick, August 1 on Prince Edward Island,
and August 5 in Manitoba [33].

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Reproduction

Reproduction and Life History

Pteridium aquilinum is a genetically diploid, sexual, homosporous fern producing haploid spores that are dispersed by air and gravity. The spores germinate to produce small, potentially bisexual gametophytes. In spite of the potential for intragametophytic self-fertilization, genetic data suggest that bracken sporophytes in nature mainly are the result of outcrossing between gametophytes (Wolf et al., 1988, 1991). Klekowski (1972) presented data showing that this outcrossing was not due to the presence of a genetic incompatibility system, but that genetic load (the presence of deleterious alleles in natural populations that minimize the number of successful self-fertilizations) might play a role in enforcing outcrossing.

In vitro studies also have shown that bracken gametophytes have an antheridiogen system (Döpp, 1950); that is, the first gametophytes developing at a site become functionally female and produce hormonal substances (antheridiogens) that cause subsequently developing gametophytes nearby to become functionally male. In fact Döpp’s initial report on the existence of antheridiogens involved the study of cultured gametophytes of Pteridium aquilinum, and the species is still used a standard for assaying the production of antheridiogen A in ferns.

The studies of Wolf et al. (1991) on plants in Britain also have shown that the high dispersability of bracken spores leads to high rates of gene flow and consequently potentially very large metapopulations.
In nature, many bracken plants rarely produce sporangia. In such populations, sexual reproduction does not occur regularly. Vegetative reproduction is thus very important in bracken and is accomplished by fragmentation of the long-creeping, branched rhizomes. Some rhizome branches are leafless and elongate extensively as a mechanism to increase the overall size and spread of the clone. Bracken is one of the largest organisms in the world. Sheffield et al. (1989b) used isozyme data to document a single clone of Pteridium aquilinum in Great Britain whose rhizome apparently covered an area 390 m in length.

Apospory on aberrant fronds in nature was demonstrated by Farlow (1889) and confirmed by Whittier (1966a). Whittier (1966b) also demonstrated in vitro that normal haploid gametophytes and diploid gametophytes resulting from apospory could be induced to become apogamous.

Creative Commons Attribution 3.0 (CC BY 3.0)

George Yatskievych

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Evolution and Systematics

Fossil History

Paleontology

The mostly northern hemisphere distribution of Pteridium aquilinum sensu stricto vs. the mostly southern hemisphere distribution of the remaining diploid species in the genus is suggestive of a Laurasian/Gondwanan split, however, there is no fossil evidence to directly confirm the development this biogeographic pattern. Currently, there is a large area of geographic overlap between the two groups in Latin America and portions of southern Asia. Rymer (1973) reviewed the fossil history of Pteridium. The oldest macrofossils attributed to the genus date to the Oligocene of Hungary, and unequivocal leaf compressions of Pteridium have been recorded from the late Miocene of England and late Pliocene of New Zealand (Oliver, 1928). Rymer reviewed the Quaternary history of Pteridium in Great Britain in somewhat more detail, noting that its distribution waxed and waned during successive glacial and interglacial stages, and that generally the current distribution of P. aquilinum is a relatively recent phenomenon affected greatly by prehistoric and historic human-mediated perturbations such as clearing of forests and introduction of livestock.
Creative Commons Attribution 3.0 (CC BY 3.0)

George Yatskievych

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Systematics or Phylogenetics

Concepts and Synonymy

Although the taxonomy of the genus Pteridium is still controversial, four or five species are often accepted in modern accounts, including: P. aquilinum (L.) Kuhn sensu stricto, P. arachnoideum (Kaulf.) Maxon, P. caudatum (L.) Maxon, P. esculentum (G. Forst.) Cockayne, and P. semihastatum (Wall. ex J. Agardh) S.B. Andrews (P. yarrabense (Domin) N.A Wakef.) (Thomson, 2004).

The list of epithets that have been applied as infraspecific taxa within P. aquilinum when the genus was still considered monospecific includes nearly 20 names. A number of these are now applied to segregate species within the genus and the taxonomic status of most others still has not been fully resolved.

Creative Commons Attribution 3.0 (CC BY 3.0)

George Yatskievych

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Classification

The genus Pteridium is a member of the homosporous fern family Dennstaedtiaceae. Generic relationships within the family still are not fully understood, but the genus is morphologically quite distinct. The taxonomy and classification within Pteridium continues to be controversial. Traditionally and as monographed by Tryon (1941), the genus was thought to comprise a single, highly variable and nearly cosmopolitan species, P. aquilinum, which could be divided into two subspecies, with a complex series of eight and four varieties respectively. However, over time, some of the morphological variants became elevated to separate species status, with the result that more than a dozen species epithets have been published within the genus. Long-term research on the systematics and phylogeny of Pteridium, mainly by John Thomson (National Herbarium of New South Wales) and his collaborators (Thomson, 2004) has resulted in the recognition of four or five species: a New and Old World northern hemisphere diploid (P. aquilinum sensu stricto), a pair of closely related New and Old World mostly southern hemisphere diploids (P. arachnoideum, P. esculentum), an uncommon neotropical tetraploid (P. caudatum), and a Malaysian/Australian tetraploid (P. semihastatum, aka. P. yarrabense). Within P. aquilinum sensu stricto, infraspecific classification also continues to be controversial, with ten or more geographically and morphologically defined subspecies possibly recognized.
Creative Commons Attribution 3.0 (CC BY 3.0)

George Yatskievych

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Functional Adaptations

Functional adaptation

Cyanide protects from herbivores: brackenfern
 

Bracken protects its leaves from being eaten by filling them with cyanide.

   
  "Bracken, that most widespread of ferns in Britain, fills its young tender leaves with cyanide. That deters most insects...By the time the leaves are mature and so tough that they seem likely to be of interest only to larger grazers such as rabbits and deer, they have manufactured a cocktail of toxins so powerful that they can cause blindness and cancer in mammals." (Attenborough 1995:70)
  Learn more about this functional adaptation.
  • Attenborough, D. 1995. The Private Life of Plants: A Natural History of Plant Behavior. London: BBC Books. 320 p.
Creative Commons Attribution Non Commercial 3.0 (CC BY-NC 3.0)

© The Biomimicry Institute

Source: AskNature

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Physiology and Cell Biology

Physiology

Physiology and Biochemistry

Much has been written on the biochemistry of bracken because of its toxicity (see under Toxicity).  As noted under Life History, Pteridium aquilinum was the first species in which the production of antheridiogens (hormones that cause gametophytes to become exclusively male, thus facilitating cross-fertilization) was detailed.  Gametophytes of the species also have been model systems for the in vitro study of gametophyte growth and development, as well as the induction of apogamy and apospory (e.g., Whittier, 1966b, c; Sobota and Partanan, 1967; Raghavan, 1969, 1970
Creative Commons Attribution 3.0 (CC BY 3.0)

George Yatskievych

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Cell Biology

Chromosomal Data

The genus Pteridium has been nearly uniformly reported as having n=52 or 2n=104 from numerous reports covering several of the described taxa within P. aquilinum (for a summary, see Löve et al., 1977). This ploidy generally is regarded as the current diploid in the genus. However, a few exceptions exist. Löve and Kjellqvist (1972) reported a count of n=26 from a plant that they referred to P. herediae. This count, which was published without documenting photos or illustrations, was later refuted as based on an aberrant cell by Sheffield et al. (1986, 1989a). Additionally, an apparent tetraploid count of 2n=208 was reported by Jarrett et al. (1983) from the Galapagos and a second tetraploid from Malaysia and Australia was inferred by Thomson (2000a, b) based on morphometric and DNA fingerprinting data (but no cytological data). However, these unusual New and Old World polyploids are best treated as allopolyploid species separate from P. aquilinum sensu stricto (Thomson, 2004). Sheffield et al. (1993) also reported an unusual, partially fertile, triploid clone from England with 2n=156, whose taxonomic affinities await further research.
Creative Commons Attribution 3.0 (CC BY 3.0)

George Yatskievych

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Molecular Biology and Genetics

Molecular Biology

Barcode data: Pteridium aquilinum

The following is a representative barcode sequence, the centroid of all available sequences for this species.


Creative Commons Attribution 3.0 (CC BY 3.0)

© Barcode of Life Data Systems

Source: Barcode of Life Data Systems (BOLD)

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Statistics of barcoding coverage: Pteridium aquilinum

Barcode of Life Data Systems (BOLDS) Stats
Public Records: 9
Specimens with Barcodes: 13
Species With Barcodes: 1
Creative Commons Attribution 3.0 (CC BY 3.0)

© Barcode of Life Data Systems

Source: Barcode of Life Data Systems (BOLD)

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Molecular Biology and Genetics

A number of systematic and phylogenetic studies have been published on the genus involving molecular and other genetic data, but thus far there has not been a comprehensive account. Papers involving Pteridium aquilinum: cpDNA restriction site analysis (Jubrael et al., 1986, 1990; Tan and Thomson, 1990b; Thomson et al., 1995); arbitrarily-primed PCR fingerprinting of nuclear genome (Thomson 2000a, b; Thomson and Alonso-Amelot, 2002; Thomson et al., 2005); ISSR analysis (Thomson et al., 2005); isozyme analysis (Wolf et al., 1988, 1991; Sheffield et al., 1989a, b, 1993, 1995; Rumsey et al., 1991; Bridges et al., 1998; Speer et al., 1999); genome size (Tan and Thomson, 1990a); chloroplast sequence data (Wolf et al., 1995; Speer, 2000); mitochondrial sequence data (Wolf et al., 1995); nuclear sequence data (Thomson et al., 1995, 2000; Wolf et al., 1995).

See under Reproduction and Life History for additional references on genetics.

Creative Commons Attribution 3.0 (CC BY 3.0)

George Yatskievych

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Conservation

The species Pteridium aquilinum is considered globally Secure. Conversely, it is considered a noxious weed (officially or unofficially) in portions or North America, Europe, New Zealand, and Australia.
Creative Commons Attribution 3.0 (CC BY 3.0)

George Yatskievych

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Conservation Status

National NatureServe Conservation Status

Canada

Rounded National Status Rank: N5 - Secure

United States

Rounded National Status Rank: N5 - Secure

Creative Commons Attribution Non Commercial 3.0 (CC BY-NC 3.0)

© NatureServe

Source: NatureServe

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

NatureServe Conservation Status

Rounded Global Status Rank: G5 - Secure

Creative Commons Attribution Non Commercial 3.0 (CC BY-NC 3.0)

© NatureServe

Source: NatureServe

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Status

Very widespread and common (3).
Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© Wildscreen

Source: ARKive

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Threats

Not threatened at present.
Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© Wildscreen

Source: ARKive

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

How to Grow (Kill)

Control of bracken is very difficult. Mechanical control of aboveground portions of the plants is ineffective, because of the deep-seated perennial rhizome, as is application of controlled burns. Plowing is somewhat effective when crop fields have been infested, but is not feasible in most natural habitats. Under natural conditions, bracken frond density decreases with increasing shade as forest canopies develop closure, but this is a lengthy process and sometimes at odds with other management objectives for given parcels of land.

On a small scale, bracken ferns can be controlled by foliar application of herbicides such as glyphosate and asulam, with repeated application to resprouting fronds necessary and the use of a surfactant to facilitate uptake of the herbicide through the waxy cuticle increasing the chances of success. At larger geographic scales, herbicides have been applied by aircraft, but this process has the potential to impact adjacent nontarget plant species.

Biological controls have thus-far not been implemented successfully to control stands of Pteridium aquilinum in nature. However, searches for potential organisms with which to develop a biocontrol program have been going on for years, principally in Great Britain, mainly involving potential fungal and insect pathogens. Source documents: Gaskin et al. (1986), Sharma and Kirkwood (1995), Womack et al. (1995); Petrov and Marrs (2000), Robinson (2000), Robinson and Page (2000), Fowler (2002).

Creative Commons Attribution 3.0 (CC BY 3.0)

George Yatskievych

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Cultivation

Pteridium is not recommended for gardens, as it is too aggressive, the deep-seated, creeping rhizomes are difficult to control, and the plants release allelopathic compounds into the soil that inhibit the growth of other plants. Occasionally, it is planted in places where a large space needs to be filled.
Creative Commons Attribution 3.0 (CC BY 3.0)

George Yatskievych

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Management

Management considerations

More info for the terms: competition, fern, fronds, litter, rhizome, shrub, tree

Competition:  Western bracken fern is competitive plant that invades cultivated
fields and disturbed areas [54,79,129,218,222,234].  It effectively
competes for soil moisture and nutrients.  Its rhizomes grow under the
roots of herbs and tree or shrub seedlings, and when the fronds emerge,
they shade the smaller plants.  In the winter dead fronds may bury other
plants and press them to the ground [46,117,150,162].  On some sites
shading may protect tree seedlings and increase survival [162].  In a
western Washington study, dense western bracken fern protected planted
Douglas-fir seedlings from snowshoe hare and black-tailed deer browsing
until the trees overtopped the western bracken fern; tree growth, however, was
slower than normal [54,55].  Control may be needed until tree seedlings
are taller than the western bracken fern and sturdy enough to withstand the
weight of dead fronds [112].  Scots pine (Pinus sylvestris) has
successfully invaded stands of dense western bracken fern (var. aquilinum) [159].

Allelopathy:  Western bracken fern's production and release of allelopathic
chemicals is an important factor in its ability to dominate other
vegetation [13,84,86].  The release of these toxic chemicals varies by
environment or perhaps by variety of western bracken fern.  In tropical areas
rainfall leaches toxins from green fronds.  Farther north no
allelopathic chemicals are released from the green fronds but are
readily leached from standing dead fronds [84].  In the Pacific
Northwest, water extracts from green fronds did not inhibit sampled
plants, but extracts from litter did [52].

A Pacific Northwest study found that water-soluble extracts from dead
western bracken fern fronds affected thimbleberry (Rubus parviflorus) and
salmonberry (R. spectabilis) germination but did not affect Douglas-fir
(Pseudotsuga menziesii).  Western bracken fern litter reduced the emergence of
all three species [217].  In Pennsylvania, water extracts from green
fronds reduced germination of black cherry (Prunus serotina) [124].  In
an Idaho study, when subalpine fir (Abies lasiocarpa), Engelmann spruce
(Picea engelmannii), Douglas-fir, and grand fir (Abies grandis) seed was
sown under western bracken fern, most of the new germinants died before shedding
seed coats [71].  Herbs may be inhibited for a full growing season after
western bracken fern is removed, apparently because active phytotoxins remain in
the soil [124,87].

Western bracken fern control:  Timing is important in any treatment of bracken
fern [68, 154,155,244].  The most effective time for treatment is summer
just after the new fronds have fully expanded and starch reserves in the
rhizome are at their lowest level [31,136,154,155,160,196,218,243].  Two
or more annual treatments and combinations of cutting and herbicide are
more effective than single treatments or even single annual treatments
[154].

Mechanical Treatment:  Cutting early in the summer, allowing the
rhizomes to regenerate a second crop of fronds, then recutting will
deplete the resources of the rhizome much faster than a single cutting.
However, single, annual cuttings or deep ploughing can be effective
during midsummer [70,154].  A north Florida slash pine (Pinus elliottii)
site with small amounts of western bracken fern was clearcut in late fall.
Debris and residual vegetation were mechanically chopped the following
April and again in August, followed by mechanical preparation and
planting.  Western bracken fern amounts remained fairly steady and did not
increase to harmful levels [35].

Biological control:  Biological methods for control of western bracken fern in
Great Britain are being investigated and two South African moths
(Conservula conisigna and Panotima sp. near angularis) appear promising.
Both moths are capable of severely damaging the fronds in the spring,
but no biocontrol agent capable of damaging the rhizomes has yet been
identified [146].  Lawton [143] evaluates potential control insects and
potential problems with their use.  The possibility of using disease
fungi, either alone or in conjunction with herbicides, to control
bracken is also being studied [25].

Chemical control:  Asulam is a relatively specific and environmentally
safe herbicide that is very effective for western bracken fern control
[26,118,129,160,197].  Asulam is more effective if the western bracken fern is
cut first [54].  Dead fronds may need to be cut away from growing trees
after spraying with asulam [212].  Glyphosate (Roundup) is also
effective and reduces carbohydrate reserves of the rhizome
[12,26,48,136,160,241].  Other effective chemical controls include
amitrole-T, dicamba, karbutilate, picloram, 4-CPA, sodium
chlorate/borate, chlorthiamid, and dichlobenil [31,165].  The
effectiveness of these is variable in the Pacific Northwest [26].  Two
applications increases control [222].  Methods and timing of herbicide
application are discussed by Hamel [103], Robinson [201], Miller and
Kidd [166], and Burrill and others [26].  Spraying vegetation with other
herbicides may reduce competition and allow western bracken fern expansion
[182,219].

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Conservation

No conservation action is required for this very common species.
Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© Wildscreen

Source: ARKive

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Relevance to Humans and Ecosystems

Benefits

Whole plant: Plant is boiled, and the water used as an antiseptic, by the Guyana Patamona. Plant is boiled along with Lantana camara and Scoparia dulcis and the water used as an herbal bath for cold sweat, by the Guyana Patamona. Juice from macerated young shoots is used as an antiinfective or for treating cuts and wounds or for treating sores, by the Guyana Patamona.

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Other uses and values

More info for the terms: fern, fresh, fronds, fuel, litter, rhizome

Western bracken fern was considered so valuable during the Middle Ages that it
was used to pay rents [202].  Western bracken fern was used as thatch for
roofing and as a fuel when a quick hot fire was desired.  The ash was
used as a source of the potash used in the soap and glass industry until
1860 and for making soap and bleach.  The rhizomes were used to dye wool
yellow and in tanning leathers [202].  Western bracken fern is still used for
winter livestock bedding in parts of Wales since it is more absorbent,
warmer, and easier to handle than straw [77,125].  It is also used as a
green mulch and compost [70,183,202].

Western bracken fern is most commonly used today as a food for humans.  The
newly emerging croziers or fiddleheads are picked in spring and may be
consumed fresh or preserved by salting, pickling, or sun drying
[120,202].  Both fronds and rhizomes have been used in brewing beer, and
rhizome starch has been used as a substitute for arrowroot [232].  Bread
can be made out of dried and powered rhizomes alone or with other flour
[202].  American Indians cooked the rhizomes, then peeled and ate them
or pounded the starchy fiber into flour [102,107,149,183].  In Japan
starch from the rhizomes is used to make confections [120,202].  Bracken
fern is grown commercially for use as a food and herbal remedy in
Canada, the United States, Siberia, China, Japan, and Brazil [70] and is
often listed as an edible wild plant [107,120].  Powdered rhizome has
been considered particularly effective against parasitic worms [79,202].
American Indians ate raw rhizomes as a remedy for bronchitis [79,183].

Western bracken fern has been found to be mutagenic and carcinogenic in rats and
mice, usually causing stomach or intestinal cancer [62,63,70,80].  It is
implicated in some leukemias, bladder cancer, and cancer of the
esophagus and stomach in humans [63,80].  All parts of the plant,
including the spores, are carcinogenic, and face masks are recommended
for people working in dense bracken [63].  The toxins in western bracken fern
pass into cow's milk [62,70,80].  The growing tips of the fronds are
more carcinogenic than the stalks [62,141].  If young fronds are boiled
under alkaline conditions, they will be safer to eat and less bitter
[63,70,120].

Western bracken fern is a potential source of insecticides and it has potential
as a biofuel [140].  Western bracken fern increases soil fertility by bringing
larger amounts of phosphate, nitrogen, and potassium into circulation
through litter leaching and stem flow; its rhizomes also mobilize
mineral phosphate [28,140,157,158,242].  Western bracken fern fronds are
particularly sensitive to acid rain which also reduces gamete
fertilization.  Both effects signal the amount of pollutants in rain
water making western bracken fern a useful indicator [64,65,66].

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Value for rehabilitation of disturbed sites

More info for the term: cover

Nonnative grasses are often seeded onto disturbed sites in some areas of
the West to control erosion.  Sites with predisturbance cover of bracken
fern do not normally need seeding and should be low in priority for such
activities [229].

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Cover Value

More info for the terms: cover, fern, litter

Western bracken fern clumps are used for cover by deer in England [43].  Birds,
including pheasants, meadow pipits, and grouse, may use it for escape
cover.  In England, woodcocks, chats, and wrens nest in western bracken fern
[172,181], and small animals such as foxes, rabbits, voles, shrews, and
mice find cover in it [181].  Sheep ticks and other insects are often
found in the decomposing litter of western bracken fern [23,77,104].

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Nutritional Value

More info for the terms: fern, fronds

The crude protein content of western bracken fern decreases during the growing
season, from 20 to 25 percent to 5 to 10 percent in fronds and from 10
to 15 percent to 2 or 3 percent in petioles (stems) [141].  Frond
carbohydrate levels are highest early in the summer and begin to drop by
mid-July [243].  Lignin, tannin, and silicate levels tend to increase
through the growing season making the plants less palatable [141].
Cyanide (HCN) levels fall during the season as do the levels of a
thiaminase which prevents utilization of B vitamins [141].  Tannin
production may be related to edaphic conditions; water stress may reduce
the amount produced [226].

Toxicity:  Western bracken fern is known to be poisonous to livestock throughout
the United States, Canada, and Europe [92,234].  Losses are greatest
when livestock is fed hay mixed with western bracken fern [234].
Simple-stomached animals like horses, pigs, and rats develop a thiamine
deficiency within a month.  Vitamin B1 is effective in curing the animal
if it is administered early [67].  Acute bracken poisoning affects the
bone-marrow of both cattle and sheep and causes anemia and hemorrhaging
which is often fatal [67,104].  Bright blindness and tumors of the jaws,
rumen, intestine, and liver are also found in sheep feeding on bracken
fern [104].  Sheep and cattle are most often poisoned by western bracken fern
when young animals are moved from an area without western bracken fern to a
field containing the fern.  Cumulative poisoning may occur in older
sheep that have ingested small amounts of western bracken fern over a period of
years [104].

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Palatability

More info for the terms: fern, fronds

Western bracken fern's palatability is usually nil to poor, although
occasionally it is eaten by livestock after autumn frosts [234].  In the
southern and northeastern United States, newly emerging fronds of
western bracken fern are most palatable to deer and livestock [92,227].  Cattle
sometimes eat it for roughage [62].  A study using captive mule deer
gave western bracken fern a low preference rating, since the deer only consumed
it in July [210].

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Importance to Livestock and Wildlife

More info for the terms: fern, fronds

In Montana, elk eat western bracken fern only in June when new fronds are
unfurling [247].  Likewise New Jersey deer use is restricted to spring
fiddleheads [227].  In the southern states western bracken fern is ranked as a
low-use forage for deer which eat it only in the spring [92].
White-tailed deer eat western bracken fern in trace amounts only in the summer
and fall [132] or not at all [116].  However, western bracken fern foliage
accumulated high concentrations of nutrients and was heavily used by
deer in Pennsylvania during the first spring following fire [99].
Rabbits occasionally eat the fronds and rhizomes [181].

Goats are the only livestock that normally eat western bracken fern [79].
Cattle feeding on lush grass may eat western bracken fern for roughage or if it
is mixed in hay [33,62]. In the Pacific Northwest sheep avoid mature
fronds of western bracken fern so it increases in cutover areas grazed by sheep
[128].  The fronds may release hydrogen cyanide (HCN) when they are
damaged (cyanogenesis), particularly the younger fronds [42,96].
Herbivores, including sheep, selectively graze young fronds that are
acyanogenic (without HCN) [43,96].

Despite western bracken fern's production of bitter-tasting compounds, chemicals
that interfere with insect growth, and toxic chemicals, western bracken fern
hosts a relatively large number and variety of herbivorous insects
[141,142].  In Great Britain 27 to 35 insect species eat western bracken fern.
The number and diversity of insect species increase toward the end of
the season, possibly because of declining levels of toxic chemicals
[141].  A study in the southwestern United States found only five to
seven insect species feeding primarily on bracken; however, in the
Southwest western bracken fern grows in a very restricted area [142].  Some
North American sawflies feed on western bracken fern [141].

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Where is it Grown

Occasionally, in gardens around the world that have sufficient space to allow for a colony.
Creative Commons Attribution 3.0 (CC BY 3.0)

George Yatskievych

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Ethnobotany

Rymer (1976) reviewed the ethnobotany of Pteridium aquilinum. Historically, dried fronds of bracken were used to stuff mattresses, as other bedding, and as litter to cover floors, because of their insecticidal properties. Whole plants were used in thatch for houses and fronds were used to shade and cover other items. The fronds also decay quickly when mixed with urine, dung, or other organic material; thus the species has been used in composting. Bracken was burned historically to produce potash, which is used in the manufacture of soap and glass, as well as in dyeing, bleaching, and wool scouring. It also was a fuel for cookfires and lime kilns. Minor uses included as a tanning agent for leather and as a substitute or adulterant for hops in beer brewing.

The emerging young fiddleheads are collected for human consumption in most regions where the fern is abundant, especially in portions of Asia. This practice is to be discouraged, however, because of the strong link between heavy ingestion of fresh or dried bracken leaves and the incidence of stomach cancer (see also under toxicity).

According to Rymer (1976), bracken had a number of medicinal uses in Europe. As with many ferns, the rhizome was used as an anthelmintic. The rhizomes and leaves also were used in various tonics and even as an aphrodesiac.

Moerman (1998 and http://herb.umd.umich.edu) noted a number of medicinal uses among North American Indian tribes, including: the use of rhizomes as an antiemetic, antihemorrhagic, analgesic, tonic, and for skin problems; an infusion of fronds used as a gynecological aid, antirheumatic, and for liver, urinary, and venereal problems; and a poultice of leaves for skin sores. Plants also were used in basketry and sleeping mats, to cover produce and fish, and cooking aid.

Creative Commons Attribution 3.0 (CC BY 3.0)

George Yatskievych

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Risks

Toxicity

Pteridium aquilinum is highly palatable, but toxic, to animals, both invertebrates and vertebrates. Several modes of action have been studied:

The fronds produce a large number of ecdysomes, which are hormones that cause uncontrolled molting in insect larvae and thus disrupt normal maturation processes.

The fronds, are cyanogenic. They contain a substance known as prunasin that is converted into the poison, hydrogen cyanide, in response to tissue damage (such as from insect predation).

The plants, particularly the rhizomes and young fronds, produce type I thiaminase, an enzyme that breaks down thiamine and thus causes vitamin B deficiency. The effects are cumulative over time and even hay contaminated with bracken can produce symptoms. The name bracken staggers has been applied to this problem in horses, but a variety of neurological symptoms occur and also anorexia, hemorrhaging, conjunctivitis, fever, muscular tremors and spasms, accelerated heartbeat, and seizures. Some of the symptoms are thought to represent more than one interacting causal agent. Mortality can be high.

The plants are rich in tannins, which bind to proteins, enzymes, and other cellular products, doing all sorts of harm in the bodies of organisms that ingest the tissues of bracken. Cooking tends to break down tannins.
The plants are carcinogenic, containing a substance known as ptaquiloside, as well as other norsesquiterpene glucosides. Regions in which humans ingest large quantities of bracken have long been known to have elevated rates of stomach and esophageal cancers, and various gastrointestinal and urinary cancers also have been observed in livestock. Related symptoms in some animals include retinal degeneration (bright blindness of sheep) and acute hemorrhagic disease (tied to degeneration of the bone marrow). Laboratory experiments on animals confirmed the link between Pteridium and these symptoms. When bracken is eaten by cattle, ptaquiloside apparently also can be transmitted through the milk, potentially leading to stomach and esophageal cancers. Even the spores are carcinogenic.

Bracken also can contribute secondarily to human health hazards. Areas with dense stands of bracken can develop a thick layer of decaying thatch from old fronds and a humid microhabitat develops under the canopy of living fronds. Such a habitat apparently promotes higher densities of ticks that are carriers of Lyme Disease.

Additionally, bracken has been shown to be allelopathic (producing compounds that inhibit the germination/growth of other plants), although the results of laboratory studies to demonstrate this have varied. Source documents: Hodge (1973), I. A. Evans (1976, 1986), W. C. Evans (1976, 1986), Gliessman (1976), Hannam (1986), Hudson (1986), Ferguson and Boyd (1988), Hirono (1990), Villalobos-Salazar et al. (1990, 1995), Brown (10995), Hopkins (1995), Ouden (1995), Potter and Pitman (1995), Alonso-Amelot et al. (2000), Simán et al. (2000), Smith et al. (2000), Burrows and Tyrl (2001), Moran (2004).

Creative Commons Attribution 3.0 (CC BY 3.0)

George Yatskievych

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Wikipedia

Pteridium aquilinum

Pteridium aquilinum nf.jpg

Pteridium aquilinum (bracken, brake or common bracken), also known as "eagle fern," is a species of fern occurring in temperate and subtropical regions in both hemispheres. The extreme lightness of its spores has led to its global distribution.

Common bracken was first described as Pteris aquilina by the father of taxonomy, Carl Linnaeus, in Volume 2 of his Species Plantarum in 1753. The origin of the specific epithet derived from the Latin aquila "eagle", but what it pertains to has been a matter of some debate. It is generally held to be the shape of the mature fronds appearing akin to an eagle's wing.[1] However, medieval scholars, including Erasmus, thought the pattern of the fibres seen in a transverse section of the stipe resembled a double-headed eagle or oak tree. It was given its current binomial name by Friedrich Adalbert Maximilian Kuhn in 1879.[2]

It was traditionally treated as the sole species in the genus Pteridium (brackens); authorities have split and recognised up to 11 species in the genus, however.

It is a herbaceous perennial plant, deciduous in winter. The large, roughly triangular fronds are produced singly, arising upwards from an underground rhizome, and grow to 1–3 m (3–10 ft) tall; the main stem, or stipe, is up to 1 cm (0.4 in) diameter at the base.

An adaptable plant, it readily colonises disturbed areas. It can even be invasive in countries where it is native, such as England, where it has invaded heather (Calluna vulgaris (L.) Hull) stands on the North Yorkshire moors.[3]

The plant contains the carcinogenic compound ptaquiloside,[4] and communities (mainly in Japan) where the young stems are used as a vegetable have some of the highest stomach cancer rates in the world.[5] Consumption of ptaquiloside-contaminated milk is thought to contribute to human gastric cancer in the Andean states of Venezuela.[6]

The spores have also been implicated as carcinogens.

It has been suggested that selenium supplementation can prevent as well as reverse the immunotoxic effects induced by ptaquiloside from Pteridium aquilinum.[7]

References[edit]

  1. ^ Austin, Daniel F. (2004). Florida ethnobotany. CRC Press. p. 551. ISBN 0-8493-2332-0. Retrieved 30 June 2010. 
  2. ^ Thomson, John A. (2004). "Towards a taxonomic revision of Pteridium (Dennstaedtiaceae).". Telopea 10 (4): 793–803. 
  3. ^ Whitehead SJ, Digby J (1997). "The morphology of bracken (Pteridium aquilinum (L.) Kuhn) in the North York Moors—a comparison of the mature stand and the interface with heather (Calluna vulgaris (L.) Hull) 1. The fronds". Annals of Applied Biology 131 (1): 103–16. doi:10.1111/j.1744-7348.1997.tb05399.x. 
  4. ^ Gomes J, Magalhães A, Michel V, Amado I, Aranha P, Ovesen RG, Hansen HC, Gärtner F, Reis CA, Touati E.,"Pteridium aquilinum and its ptaquiloside toxin induce DNA damage response in gastric epithelial cells, a link with gastric carcinogenesis". Toxicol Sci. 2011 Dec 5;
  5. ^ I A Evans, B Widdop, R S Jones, G D Barber, H Leach, D L Jones, and R Mainwaring-Burton (1971). "The possible human hazard of the naturally occurring bracken carcinogen". Biochem J. 124 (2): 29P–30P. PMC 1177200. PMID 5158492. 
  6. ^ Alonso-Amelot M.E., Avendano M. "Possible association between gastric cancer and bracken fern in Venezuela: An epidemiologic study." International Journal of Cancer. 91 (2) (pp 252-259), 2001.
  7. ^ Latorre A.O., Caniceiro B.D., Wysocki H.L., Haraguchi M., Gardner D.R., Gorniak S.L.,"Selenium reverses Pteridium aquilinum-induced immunotoxic effects. Food and Chemical Toxicology. 49 (2) (pp 464-470), 2011
Creative Commons Attribution Share Alike 3.0 (CC BY-SA 3.0)

Source: Wikipedia

Unreviewed

Article rating from 1 person

Average rating: 2.0 of 5

Notes

Common Names

Guyana Patamona: kam-bail-yik.

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Comments

In accord with the most recent revision (R. M. Tryon 1941) of the genus, Pteridium is treated here as a single widespread species composed of two subspecies with 12 varieties. So treated, it is probably the most widespread species of all vascular plants, with the exception of a few annual weeds (F. H. Perring and B. G. Gardner 1976). The plants are generally aggressive, invading disturbed areas as weeds in pastures, cultivated fields, and roadsides. In Europe, it was harvested and burned to produce potash. Although croziers are eaten in many temperate cultures, bracken has been shown to contain thiaminase (and other compounds with mutagenic and carcinogenic properties). 

 Disagreement exists among taxonomists regarding the rank that should be accorded to the taxa treated herein as varieties. In a survey of the genus, C. N. Page (1976) noted uniform chromosome numbers and flavonoid compositions of the varieties. D. B. Lellinger (1985) separated the genus into at least two species based on morphology, recognizing as species the subspecies of R. M. Tryon (1941). J. T. Mickel and J. M. Beitel (1988) reported sympatric occurrence in Mexico of three taxa that maintained consistent characteristics and only rarely produced plants with combined characteristics. They suggested that these three taxa should be considered as species that occasionally hybridize. P. J. Brownsey (1989) reported that two different brackens in Australia formed sterile hybrids and should be treated as species. Modern systematic studies are needed to evaluate the status and rank of the four North American varieties. As treated below, Pteridium aquilinum var. pubescens , var. latiusculum , and var. pseudocaudatum are in subsp. aquilinum , and var. caudatum is in subsp. caudatum (Linnaeus) Bonaparte.

Creative Commons Attribution Non Commercial Share Alike 3.0 (CC BY-NC-SA 3.0)

© Missouri Botanical Garden, 4344 Shaw Boulevard, St. Louis, MO, 63110 USA

Source: Missouri Botanical Garden

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

References and More Information

People

Creative Commons Attribution 3.0 (CC BY 3.0)

George Yatskievych

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Editor's Links

Creative Commons Attribution 3.0 (CC BY 3.0)

George Yatskievych

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Names and Taxonomy

Taxonomy

Common Names

More info for the term: fern

western bracken fern
bracken
brake fern
brake
hog-brake
grande fougere
fougere d'aigle
warabi
eagle fern
western bracken
eastern bracken

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

More info for the term: fern

The currently accepted scientific name of western bracken fern is Pteridium
aquilinum (L.) Kuhn. At this time western bracken fern is considered a single,
worldwide species, although some disagree [42,73,189,232]. There are
two recognized subspecies: aquilinum (formerly typicum) in the Northern
Hemisphere and caudatum in the Southern Hemisphere. Of the four
varieties of subspecies caudatum, one, var. caudatum, grows as far north
as southern Florida. Of the eight varieties in subspecies aquilinum,
three grow in North America and one in Hawaii [189,232].

In this report the main emphasis will be given to subspecies aquilinum
and the three main North American varieties of this subspecies:

P. a. var. pubescens
P. a. var. pseudocaudatum
P. a. var. latiusculum

Western bracken fern is used for all varieties. Var. aquilinum is very
closely related to the three North American varieties listed above [42,
232] and has been studied more intensely. Where information concerning
it or other non-North American western bracken fern is included, either the
varietal name or the location is given.

Where varieties of western bracken fern overlap, intergradation between them
occurs. Intermediates between P. a. var. pubescens and P. a. var. latiusculum occur
along the eastern edge of var. pubescens' range in Wyoming and Colorado
and perhaps in Michigan and Wisconsin. Likewise, where the ranges of
P. a. var. latiusculum and P. a. var. pseudocaudatum overlap, intermediates may be
found [73,189,232].

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Synonyms

Pteris aquilina
Asplenium aquilinum
Allosorus aquilinus
Ornithopteris aquilina
Filix aquilina
Filix-foemina aquilina
Pteridium aquilinum var. lanuginosum
Pteris latiuscula
Pteridium aquilinum var. champlainese

Trusted

Article rating from 0 people

Default rating: 2.5 of 5

Disclaimer

EOL content is automatically assembled from many different content providers. As a result, from time to time you may find pages on EOL that are confusing.

To request an improvement, please leave a comment on the page. Thank you!