Invasive Species Compendium

Detailed coverage of invasive species threatening livelihoods and the environment worldwide

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Nephrolepis brownii
(Asian swordfern)

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Datasheet

Nephrolepis brownii (Asian swordfern)

Summary

  • Last modified
  • 19 November 2018
  • Datasheet Type(s)
  • Invasive Species
  • Preferred Scientific Name
  • Nephrolepis brownii
  • Preferred Common Name
  • Asian swordfern
  • Taxonomic Tree
  • Domain: Eukaryota
  •   Kingdom: Plantae
  •     Phylum: Pteridophyta
  •       Class: Filicopsida
  •         Family: Nephrolepidaceae
  • Summary of Invasiveness
  • Nephrolepis brownii, commonly known as Asian swordfern, is native to Southeast Asia and has been introduced to the tropical Americas, where it has become naturalized and invasive. Although its introduced status...

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Pictures

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PictureTitleCaptionCopyright
Nephrolepis brownii (Asian swordfern); habit. Broward County, Florida, USA. November 2003
TitleHabit
CaptionNephrolepis brownii (Asian swordfern); habit. Broward County, Florida, USA. November 2003
Copyright©Forest Starr & Kim Starr - CC BY 4.0
Nephrolepis brownii (Asian swordfern); habit. Broward County, Florida, USA. November 2003
HabitNephrolepis brownii (Asian swordfern); habit. Broward County, Florida, USA. November 2003©Forest Starr & Kim Starr - CC BY 4.0
Nephrolepis brownii (Asian swordfern); habit. Wahinepee, Maui, Hawaii, USA. August 2002
TitleHabit
CaptionNephrolepis brownii (Asian swordfern); habit. Wahinepee, Maui, Hawaii, USA. August 2002
Copyright©Forest Starr & Kim Starr - CC BY 4.0
Nephrolepis brownii (Asian swordfern); habit. Wahinepee, Maui, Hawaii, USA. August 2002
HabitNephrolepis brownii (Asian swordfern); habit. Wahinepee, Maui, Hawaii, USA. August 2002©Forest Starr & Kim Starr - CC BY 4.0
Nephrolepis brownii (Asian swordfern); habit. At base of a greenhouse, Kilauea Pt NWR, Kauai, Hawaii, USA. March 2013
TitleHabit
CaptionNephrolepis brownii (Asian swordfern); habit. At base of a greenhouse, Kilauea Pt NWR, Kauai, Hawaii, USA. March 2013
Copyright©Forest Starr & Kim Starr - CC BY 4.0
Nephrolepis brownii (Asian swordfern); habit. At base of a greenhouse, Kilauea Pt NWR, Kauai, Hawaii, USA. March 2013
HabitNephrolepis brownii (Asian swordfern); habit. At base of a greenhouse, Kilauea Pt NWR, Kauai, Hawaii, USA. March 2013©Forest Starr & Kim Starr - CC BY 4.0
Nephrolepis brownii (Asian swordfern); habit. West Maui, Maui, Hawaii, usa. November 2009
TitleHabit
CaptionNephrolepis brownii (Asian swordfern); habit. West Maui, Maui, Hawaii, usa. November 2009
Copyright©Forest Starr & Kim Starr - CC BY 4.0
Nephrolepis brownii (Asian swordfern); habit. West Maui, Maui, Hawaii, usa. November 2009
HabitNephrolepis brownii (Asian swordfern); habit. West Maui, Maui, Hawaii, usa. November 2009©Forest Starr & Kim Starr - CC BY 4.0
Nephrolepis brownii (Asian swordfern); habit, showing a single frond. At base of a greenhouse. Kilauea Pt NWR, Kauai, Hawaii, USA. March 2013.
TitleHabit
CaptionNephrolepis brownii (Asian swordfern); habit, showing a single frond. At base of a greenhouse. Kilauea Pt NWR, Kauai, Hawaii, USA. March 2013.
Copyright©Forest Starr & Kim Starr - CC BY 4.0
Nephrolepis brownii (Asian swordfern); habit, showing a single frond. At base of a greenhouse. Kilauea Pt NWR, Kauai, Hawaii, USA. March 2013.
HabitNephrolepis brownii (Asian swordfern); habit, showing a single frond. At base of a greenhouse. Kilauea Pt NWR, Kauai, Hawaii, USA. March 2013.©Forest Starr & Kim Starr - CC BY 4.0
Nephrolepis brownii (Asian swordfern); undersurface of a frond, with sori visible. From a greenhouse, Kilauea Pt NWR, Kauai, Hawaii, USA. March 2013.
TitleFrond
CaptionNephrolepis brownii (Asian swordfern); undersurface of a frond, with sori visible. From a greenhouse, Kilauea Pt NWR, Kauai, Hawaii, USA. March 2013.
Copyright©Forest Starr & Kim Starr - CC BY 4.0
Nephrolepis brownii (Asian swordfern); undersurface of a frond, with sori visible. From a greenhouse, Kilauea Pt NWR, Kauai, Hawaii, USA. March 2013.
FrondNephrolepis brownii (Asian swordfern); undersurface of a frond, with sori visible. From a greenhouse, Kilauea Pt NWR, Kauai, Hawaii, USA. March 2013.©Forest Starr & Kim Starr - CC BY 4.0
Nephrolepis brownii (Asian swordfern); undersurface of a frond, with sori visible. West Maui, Maui, Hawaii, usa. November 2009.
TitleFrond, with sori
CaptionNephrolepis brownii (Asian swordfern); undersurface of a frond, with sori visible. West Maui, Maui, Hawaii, usa. November 2009.
Copyright©Forest Starr & Kim Starr - CC BY 4.0
Nephrolepis brownii (Asian swordfern); undersurface of a frond, with sori visible. West Maui, Maui, Hawaii, usa. November 2009.
Frond, with soriNephrolepis brownii (Asian swordfern); undersurface of a frond, with sori visible. West Maui, Maui, Hawaii, usa. November 2009.©Forest Starr & Kim Starr - CC BY 4.0
Nephrolepis brownii (Asian swordfern); extreme close-up of sori (via photomicrography). Source material from West Maui, Maui, Hawaii, USA. November 2009.
TitleSori
CaptionNephrolepis brownii (Asian swordfern); extreme close-up of sori (via photomicrography). Source material from West Maui, Maui, Hawaii, USA. November 2009.
Copyright©Forest Starr & Kim Starr - CC BY 4.0
Nephrolepis brownii (Asian swordfern); extreme close-up of sori (via photomicrography). Source material from West Maui, Maui, Hawaii, USA. November 2009.
Sori Nephrolepis brownii (Asian swordfern); extreme close-up of sori (via photomicrography). Source material from West Maui, Maui, Hawaii, USA. November 2009.©Forest Starr & Kim Starr - CC BY 4.0

Identity

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Preferred Scientific Name

  • Nephrolepis brownii (Desv.) Hovenkamp & Miyam.

Preferred Common Name

  • Asian swordfern

Other Scientific Names

  • Nephrolepis acutangula C.Presl
  • Nephrolepis floccigera (Blume) T. Moore
  • Nephrolepis floccigera T.Moore
  • Nephrolepis multiflora (Roxb.) C.V. Morton.
  • Nephrolepis multiflora (Roxb.) F.M. Jarrett ex C.V. Morton
  • Nephrolepis pubescens Copel.
  • Nephrolepis tomentosa Alderw.

Local Common Names

  • New Zealand: rough sword fern

Summary of Invasiveness

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Nephrolepis brownii, commonly known as Asian swordfern, is native to Southeast Asia and has been introduced to the tropical Americas, where it has become naturalized and invasive. Although its introduced status is not clear for Oceania, the plant is considered as native in the parts of the continent where it occurs. In Hawaii and Florida, USA, where its invasiveness has been reported as critical, efforts have been undertaken to keep the spreading of N. brownii under control. N. brownii is a popular ornamental which has contributed to its spread, along with the fact it produces wind-dispersed spores and can reproduce vegetatively via rhizomes.

Taxonomic Tree

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  • Domain: Eukaryota
  •     Kingdom: Plantae
  •         Phylum: Pteridophyta
  •             Class: Filicopsida
  •                 Family: Nephrolepidaceae
  •                     Genus: Nephrolepis
  •                         Species: Nephrolepis brownii

Notes on Taxonomy and Nomenclature

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Nephrolepis is a genus of ferns of the Nephrolepidaceae family comprising 19 accepted species (Hovenkamp & Miyamoto 2015). Nephrolepis brownii (Desv.) Hovenkamp & Miyam. has been referred to under the synonymous names Nephrolepis acutangula C. Presl, Nephrolepis floccigera T. Moore, Nephrolepis multiflora (Roxb.) F.M. Jarrett ex C.V. Morton, Nephrolepis pubescens Copel., Nephrolepis tomentosa Alderw. (Hovenkamp & Miyamoto, 2005), and has most likely been misidentified as Nephrolepis hirsutula (G. Forst.) C. Presl (Wiersema and Leon, 2013), Nephrolepis exaltata (L.) Schott (New Zealand Plant Conservation Network, 2005) or Nephrolepis falcata (Cav.) C. Chr. (US Fish and Wildlife Service, 2008). Other misidentifications are to be expected, and without reference to voucher material, definite dismissal of such misidentifications is not possible. N. brownii and N. hirsutula have sometimes been regarded as the same species, but based on the phylogenetic analyses of Hennequin et al. (2010), they do not appear to even be closely related.

Description

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Adapted from Hovenkamp and Miyamoto (2005):

N. brownii generally forms tufts of five or six fronds on upright rhizomes. The plant spreads by stolons, which often form stilts that support the upright rhizome. Stolons (1.5-2.5 mm thick) branch in widely diverging angles. Scales on stolons can be sparse, appressed, or spreading. Fronds become dark green when dry, and bear scattered, linear scales along their veins, 70-130 by 10-12 cm, stipe 14-37 cm long. The lamina is more or less strongly reduced at the base, tapering over 25-35 cm. Basal pinnae 1.5-2 cm long, 2-5 cm distant, middle pinnae are straight or slightly falcate. Sterile pinnae (6 by 1.4 cm) are slightly to strongly unequal at the base, basiscopic base rounded or cordate, acroscopic base truncate, strongly auricled (usually with a narrow auricle), margin in basal part entire or crenate, apex acute. Fertile pinnae (5.5-7 by 0.9 cm) have a more distinctly serrate margin than the sterile pinnae. Pinnae are covered with basal scales (3.5 by 1.3 mm), which are peltate and appressed. The scales on the rachis are dense, spreading, with a translucent appearance or light brown. The scales on the lamina are usually persistent, often also persistent on the upper surface. Hairs on lamina are absent, but constantly present on midrib. Sori (groups of sporangia) are round and marginal, and they form 25 to 27 pairs on fully fertile pinnae. The indusium (the membrane covering the sori) is kidney-shaped.
 

Plant Type

Top of page Herbaceous
Perennial
Vegetatively propagated

Distribution

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Although it is not certain whether Nephrolepis taxa originated in the Boreotropical regions, they probably dispersed to the Palaeotropics during the Oligocene (Hennequin et al., 2010). Several Nephrolepis species are cultivated as ornamentals, and because of escapes and subsequent naturalization, the natural distribution patterns are not always clear (Darnaedi and Praptosuwiryo, 2003). Based on the distribution of early collections, N. brownii is likely native in Malesia (Hovenkamp and Miyamoto, 2005). Although its introduced status is not clear for the whole of Oceania, the plant is considered as native in the Kermadec Islands (New Zealand Plant Conservation Network, 2005). In contrast, there are no records of its occurrence in Africa, and it appears to be uncommon in most parts of the Indian subcontinent.

Distribution Table

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The distribution in this summary table is based on all the information available. When several references are cited, they may give conflicting information on the status. Further details may be available for individual references in the Distribution Table Details section which can be selected by going to Generate Report.

Continent/Country/RegionDistributionLast ReportedOriginFirst ReportedInvasiveReferenceNotes

Asia

BangladeshPresentGBIF, 2013
CambodiaPresentGBIF, 2013
ChinaPresentGBIF, 2013
-FujianPresentGBIF, 2013
-GuangxiPresentGBIF, 2013
-GuizhouPresentGBIF, 2013
-HainanPresentGBIF, 2013
-YunnanPresentGBIF, 2013
IndiaPresentGBIF, 2013
IndonesiaPresentPresent based on regional distribution.
-SulawesiPresentGBIF, 2013
JapanPresentGBIF, 2013
-Ryukyu ArchipelagoPresentGBIF, 2013
LaosPresentGBIF, 2013
MalaysiaPresentPresent based on regional distribution.
-Peninsular MalaysiaPresentGBIF, 2013
MyanmarPresentGBIF, 2013
PhilippinesPresentGBIF, 2013
SingaporePresentGBIF, 2013
Sri LankaPresentGBIF, 2013
TaiwanPresentGBIF, 2013
ThailandPresentGBIF, 2013
VietnamPresentGBIF, 2013

North America

MexicoPresentIntroducedGBIF, 2013
USAPresentIntroducedGBIF, 2013
-FloridaPresentIntroduced1940 Invasive Nauman, 1981
-HawaiiWidespreadIntroduced1981 Invasive Pratt et al., 2011; GBIF, 2013Colonization occurred in Volcanoes National Park between 1981 and 2008

Central America and Caribbean

BahamasIntroducedGBIF, 2013
BarbadosIntroducedGBIF, 2013
BelizeIntroducedGBIF, 2013
Cayman IslandsIntroducedGBIF, 2013
Costa RicaIntroducedGBIF, 2013
CubaIntroducedGBIF, 2013
DominicaIntroducedGBIF, 2013
El SalvadorIntroducedGBIF, 2013
GrenadaIntroducedGBIF, 2013
GuadeloupeIntroducedGBIF, 2013
GuatemalaIntroducedGBIF, 2013
HondurasIntroducedGBIF, 2013
JamaicaIntroducedGBIF, 2013
MartiniqueIntroducedGBIF, 2013
MontserratIntroducedGBIF, 2013
NicaraguaIntroducedGBIF, 2013
PanamaIntroducedGBIF, 2013
Puerto RicoWidespreadIntroduced1940 Invasive Nauman, 1981
Saint LuciaPresentIntroduced Invasive Krauss et al., 2008; Graveson, 2012Replacing indigenous Nephrolepis rivularis; risk in disturbed and burnt habitats
Saint Vincent and the GrenadinesIntroducedGBIF, 2013
United States Virgin IslandsIntroducedGBIF, 2013

South America

BoliviaIntroducedGBIF, 2013
BrazilIntroducedGBIF, 2013
-AcreIntroducedGBIF, 2013
-AmazonasIntroducedGBIF, 2013
-BahiaIntroducedGBIF, 2013
-ParaIntroducedGBIF, 2013
-Rio de JaneiroIntroducedGBIF, 2013
-Sao PauloIntroducedGBIF, 2013
ColombiaIntroducedGBIF, 2013
PeruIntroducedGBIF, 2013
VenezuelaIntroducedGBIF, 2013

Oceania

AustraliaPresentGBIF, 2013
FijiIntroducedGBIF, 2013
New ZealandNativeNew Zealand Plant Conservation Network, 2005At risk – naturally uncommon
Papua New GuineaIntroducedGBIF, 2013

History of Introduction and Spread

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N. brownii was introduced to the Americas, where it is spreading as a weed and classified as an invasive species in Florida (Florida Exotic Pest Plant Council, 2013). In Hawaii, USA, it is considered an alien plant (Pratt et al., 2012). Based on collection records, Nauman (1981) states that N. brownii is likely to have arrived in Florida, USA, in the late 1940s or 1950s; however, these data are inconclusive. The specimens used for Nauman’s revision were originally identified as Nephrolepis multiflora, but have been rectified as N. brownii (University of Florida Herbarium, 2015). N. brownii was introduced in Puerto Rico around 1940 (Robinson et al., 2010). While Brown and Brown (1931) suggest it is also introduced in southeast Polynesia, the earliest collections in that area suggest that the Polynesian settlers must have brought it into the area (Hovenkamp and Miyamoto, 2005).

Introductions

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Introduced toIntroduced fromYearReasonIntroduced byEstablished in wild throughReferencesNotes
Natural reproductionContinuous restocking
Florida 1940 Horticulture (pathway cause) Yes Nauman (1981)
Puerto Rico 1940 Horticulture (pathway cause) Yes Nauman (1981)
USA Horticulture (pathway cause) Yes Hovenkamp and Miyamoto (2005)

Risk of Introduction

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Given that N. brownii is intentionally planted as an ornamental, the risk of further introductions is potentially high. Further, the unintentional spreading of Nephrolepis species by people and, particularly, the invasion model of N. brownii (Robinson et al., 2010) exacerbates its invasiveness. N. brownii is listed as Category I invasive (demonstrated ecological damage) on the Florida Exotic Pest Plant Council’s 2013 Invasive Plant List.

Habitat

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Most Nephrolepis species grow in thickets (Holttum, 1938), preferring acidic, humus-rich habitats such as peat swamps or leaf bases of palms (Darnaedi and Praptosuwiryo, 2003). They can occur in disturbed sites, often near canals and other water bodies with loose and well-drained soil, frequently with full exposure to the sun (Nauman, 1981).

Habitat List

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CategorySub-CategoryHabitatPresenceStatus
Terrestrial
Terrestrial – ManagedDisturbed areas Present, no further details Natural
Rail / roadsides Present, no further details Harmful (pest or invasive)
Rail / roadsides Present, no further details Natural
Terrestrial ‑ Natural / Semi-naturalRocky areas / lava flows Present, no further details Harmful (pest or invasive)
Freshwater
Irrigation channels Secondary/tolerated habitat Natural
Lakes Secondary/tolerated habitat Natural
Reservoirs Secondary/tolerated habitat Natural
Rivers / streams Secondary/tolerated habitat Natural
Ponds Secondary/tolerated habitat Natural

Biology and Ecology

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Genetics

Basic chromosome number for Nephrolepis species is 41, and most species appear to contain diploids only, with additional tetraploids reported in what is likely N. brownii (Löve et al., 1977).

Reproductive Biology

Adapted from de Winter and Amoroso (2003):

The dominant stage in the life history of pteridophytes is the generation that produces the spores and therefore is called the sporophyte. The sporophyte forms spores by meiosis (the type of cell division that reduces the number of chromosomes to half the number that are in the nuclei of the sporophyte cells). Nephrolepis species (like other pteridophytes with creeping rhizomes) can spread by spores, but also by the formation of plantlets growing on long-creeping stolons, for which growth rates of 2 cm per day are reported in a related species (Espagnac 1973). Artificially, they can easily be propagated by divisions of stolons.

Physiology and Phenology

According to Darnaedi and Praptosuwiryo (2003), under extreme dry conditions, some Nephrolepis species rapidly shed their pinnae, leaving only dry rachises; however, when conditions improve, a new flush of leaves will develop quickly. The rachis of the leaves shows a kind of perennial growth, which accounts for the crozier-like apex of many leaves. These may continue to produce a new pinnae long after the older pinnae have shed their spores or fallen off.

Associations

The findings of Outman (2012) suggest that exotic fern species such as N. brownii can be as successful in forming relationships with mycorrhizal fungi as closely related native species growing in the same habitats.

Environmental Requirements

Some cultivars of Nephrolepis tolerate temperatures down to 0 °C (Darnaedi and Praptosuwiryo, 2003). The specimens of N. brownii reviewed by Xing et al. (2013) and Hovenkamp and Miyamoto (2005) were collected both in forests and open vegetation (roadsides, riverbanks, open thickets) at altitudes between 0 and 1700 m.a.s.l, in tropical climate zones.
 

Climate

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ClimateStatusDescriptionRemark
Af - Tropical rainforest climate Preferred > 60mm precipitation per month
Cf - Warm temperate climate, wet all year Tolerated Warm average temp. > 10°C, Cold average temp. > 0°C, wet all year

Latitude/Altitude Ranges

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Latitude North (°N)Latitude South (°S)Altitude Lower (m)Altitude Upper (m)
30 30

Soil Tolerances

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Soil drainage

  • free

Notes on Natural Enemies

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Although Nephrolepis species are generally pest resistant, cultivars are particularly susceptible to botrytis, fern scale, whitefly, slugs, and snails (Darnaedi and Praptosuwiryo, 2003). In spite of the insufficient evidence, Gregor (1938) has noted the possible susceptibility of Nephrolepis spp. to “mosaic” and virus diseases. Moreover, the gall mite Eriophyes pauropus, common in the Old World (Docters van Leeuwen, 1967), infects the leaves of Nephrolepis species, inducing the fern to form galls on the leaf blade and sori (Docters van Leeuwen-Reijnvaan, 1921).

Means of Movement and Dispersal

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N. brownii shows the same model of colonization observed in the highly invasive Pteridium and other scrambling ferns (Robinson et al., 2010). This type of ferns rapidly colonizes disturbed land by means of rhizomes that form extensive stands and are able to dominate a landscape for decades (Marrs and Watt, 2006). Pteridium ferns (and N. brownii, as noted by Robinson et al., 2010) consolidate their competitive advantage by shading, occupying the available soil space with rhizomes, and forming a litter layer that inhibits the establishment of other species by burial of their seeds and harboring seed predators.

Pathway Causes

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CauseNotesLong DistanceLocalReferences
Garden waste disposal Yes Langeland, 2001
Horticulture Yes Nauman, 1981

Impact

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In spite of its invasive status in the USA, the extent of the social, environmental, and economic impact of its invasiveness remains unknown.

Environmental Impact

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Impact on Biodiversity

Generally, Nephrolepis species are considered a threat to native species.

N. brownii shows the same model of colonization observed in the highly invasive Pteridium and other scrambling ferns (Robinson et al., 2010). This type of ferns rapidly colonizes disturbed land by means of rhizomes that form extensive stands and are able to displace native vegetation and dominate a landscape for decades (Marrs and Watt, 2006). Pteridium ferns (and N. brownii, as noted by Robinson et al., 2010) consolidate their competitive advantage by shading, occupying the available soil space with rhizomes, and forming a litter layer that inhibits the establishment of other species by burial of their seeds and harboring seed predators.

In Florida, USA, the invasiveness of N. brownii is exacerbated by the year-round spore production (MacDonald et al., 2008).

In Saint Lucia in the Caribbean, N. brownii is invasive and has become very common in many areas. It has been reported that is is probably replacing Nephrolepis rivularus, a native and rare epiphytic herb (Graveson, 2012; Krauss et al., 2008).

Risk and Impact Factors

Top of page Invasiveness
  • Proved invasive outside its native range
  • Pioneering in disturbed areas
  • Tolerant of shade
  • Reproduces asexually
Impact outcomes
  • Threat to/ loss of native species
Impact mechanisms
  • Competition - shading
  • Competition - smothering
  • Competition
  • Rapid growth
  • Rooting
Likelihood of entry/control
  • Highly likely to be transported internationally deliberately
  • Difficult to identify/detect in the field

Uses

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Economic Value

In Southeast Asia, wild and cultivated species of Nephrolepis are offered for sale as ornamentals on local markets; however, statistics of their economic value are not available (Darnaedi and Praptosuwiryo, 2003). Although Wiersema and León (1999) include five species of Nephrolepis amongst the world’s economically important plants, among which is probably N. brownii (as N. hirsutula). Most of the trade is in cultivars of Nephrolepis “bostoniensis” (referred to by Wiersema and Leon (2013) as Nephrolepis exaltata). The economic impact resulting from the cultivation of N. brownii is not known.

Social Benefit

Quantitative data on the social benefits of N. brownii are absent. However, authors and collectors have listed important uses of the fern species that are now considered synonyms N. brownii. In Java and New Guinea, the very young curled leaves of N. hirsutula are eaten cooked or steamed as a vegetable, or applied as a poultice on swelling wounds and boils (Ochse, 1931). In the Philippines, fibers extracted from the stems of N. hirsutula are used in the manufacture of wickerwork (Zamora and Co, 1986). In Papua New Guinea, the leaves of Nephrolepis species are placed amongst bones in death ceremonies (Darnaedi and Praptosuwiryo, 2003).
 

Uses List

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General

  • Ritual uses

Human food and beverage

  • Vegetable

Materials

  • Fibre

Ornamental

  • Potted plant

Similarities to Other Species/Conditions

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Species within the genus Nephrolepis can appear similar. Hovenkamp and Miyamoto (2005) note that difficulty to distinguish N. brownii and N. hirsutula may be due to occasional hybridization. Further, they highlight a few “spot” characters for the identification of sterile specimens. These are: in N. brownii and N. hirsutula the base of the pinnae is very conspicuously auricled; in N. brownii and N. hirsutula the lamina’s indument is scaly and persistent; in N. brownii and N. cordifolia, the rachis’ indument is dense, scaly, and pale. In N. brownii, N. exaltata, and N. biserrata, tubers are always absent. In contrast, in N. cordifolia, tubers can be present (Langeland, 2001, Hovenkamp & Miyamoto 2005), but are easily overlooked, as when a plant is uprooted by pulling the tubers may remain in the substrate.

Prevention and Control

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Control

Cultural control and sanitary measures


It is recommended to plant native or non-invasive alternatives. Although avoidance of transport of spores from one area to the next via people, vehicles and other equipment (MacDonald et al., 2008) is recommended, for Nephrolepis species particular attention must also be paid to the transport of stolons or stolon-fragments in soil.

Physical/mechanical control

Langeland (2001) suggested hand pulling as a method to remove invasive fern plants. However, he states, plants easily break off, leaving plant parts in the ground from which regrowth will occur. Because some plants are difficult to up-root and the rachis can cut the skin, it is recommended to wear heavy gloves. Moreover, it is important not to dispose of removed specimens where they cause new infestations.

Biological control

There are no known biological agents for the control of N. brownii (MacDonald et al., 2008).

Chemical control

Nephrolepis spp. can be killed with herbicide products containing glyphosate as the active ingredient. Follow-up applications are necessary (Langeland, 2001).
 

Gaps in Knowledge/Research Needs

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Without underestimating the work of others, yet to date, information on the impact and extent of invasiveness of Nephrolepis species could be misleading. This is caused by the failure of authors to apply the latest taxonomic insights, resulting in the frequent use of scientific names that refer to ferns that were considered species of their own in the past but are now synonyms of other species, or that refer to species that are frequently confused with other species. As noted by Robinson et al. (2010), a salient requirement in the management of invasive ferns is to “know your enemy”. Therefore, reliable identification of N. brownii, and other Nephrolepis species, is of utmost importance to understand whether these ferns are a threat in the first place, as well as to assess the ecological and social relevance of their impact.

References

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Brown EDW; Brown FBH, 1931. Flora of Southeastern Polynesia. II. Pteridophytes. Bernice P Bishop Museum Bulletin, 89.

Darnaedi D; Praptosuwiryo TN, 2003. Nephrolepis Schott. Cryptogams: Ferns and fern allies. In: Plant Resources of South-East Asia, 12(2) [ed. by Winter, W. P. de \Amoroso, V. B.]. Leiden, Netherlands: Backhuys Publishers.

Docters van Leeuwen-Reijnvaan WJ, 1921. About the leaf galls formed by Eriophyes pauropus Nal on different types of Nephrolepis. (Über die von Eriophyes pauropus Nal an verschiedenen Arten von Nephrolepis gebildeten Blattgallen.) Annales du Jardin Botanique de Buitenzorg, 21:83.

Docters van Leeuwen-Rijnvaan WJ, 1938. Manual of Pteridology [ed. by Verdoorn, F. \Alston, A. H. G.]., Amsterdam: A Asher.

Espagnac H, 1973. Polymorphic axes Nephrolepis biserrata. Experimental analysis of the determinism of their structures. (Les axes polymorphes de Nephrolepis biserrata. Analyse experimentale du determinisme de leurs structures.) Ann. Sci. Nat., Bot. ser, 12(14):223-286.

Fish and Wildlife Service US(USFWS), 2008. Endangered and threatened wildlife and plants: initiation of 5-year status reviews of 70 species in Idaho, Montana, Oregon, Washington and the Pacific Islands., USA: US Fish and Wildlife Service.

Florida Exotic Pest Plant Council, 2013. Florida Exotic Pest Plant Council's 2013 list of invasive plant species. Florida, USA: Florida Exotic Pest Plant Council. http://www.fleppc.org/list/2013/FLEPPCPlantList2013-PRINTABLEwithlinkstoCAIPpages.pdf

GBIF, 2013. Global Biodiversity Information Facility. Global Biodiversity Information Facility (GBIF). http://data.gbif.org/species/

Graveson R, 2012. The Plants of Saint Lucia (in the Lesser Antilles of the Caribbean). The Plants of Saint Lucia (in the Lesser Antilles of the Caribbean). http://www.saintlucianplants.com

Gregor MJF, 1938. Manual of Pteridology [ed. by Verdoorn, F. \Alston, A. H. G.]. Amsterdam, Netherlands: A Asher.

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Links to Websites

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WebsiteURLComment
Center for Aquatic and Invasive Plantshttp://plants.ifas.ufl.edu/
GBIF Networkwww.gbif.net
GISD/IASPMR: Invasive Alien Species Pathway Management Resource and DAISIE European Invasive Alien Species Gatewayhttps://doi.org/10.5061/dryad.m93f6Data source for updated system data added to species habitat list.
New Zealand Plant Conservation Networkhttp://www.nzpcn.org.nz/

Contributors

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15/02/2016 Updated by:

Peter Hovenkamp, Naturalis Biodiversity Centre, Netherlands

30/05/2015 Original text by:

Diana Quiroz, Naturalis Biodiversity Centre, Netherlands

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