Cookies on Invasive Species Compendium

Like most websites we use cookies. This is to ensure that we give you the best experience possible.

Continuing to use www.cabi.org means you agree to our use of cookies. If you would like to, you can learn more about the cookies we use.

Datasheet

Spartina alterniflora (smooth cordgrass)

Summary

  • Last modified
  • 11 October 2017
  • Datasheet Type(s)
  • Invasive Species
  • Host Plant
  • Preferred Scientific Name
  • Spartina alterniflora
  • Preferred Common Name
  • smooth cordgrass
  • Taxonomic Tree
  • Domain: Eukaryota
  •   Kingdom: Plantae
  •     Phylum: Spermatophyta
  •       Subphylum: Angiospermae
  •         Class: Monocotyledonae
  • Summary of Invasiveness
  • S. alterniflora, along with other Spartina was initially seen by many coastal engineers as a species that could be used to create natural erosion control barriers. S. alterniflora is a rhizomatous p...

Don't need the entire report?

Generate a print friendly version containing only the sections you need.

Generate report

Pictures

Top of page
PictureTitleCaptionCopyright
Spartina alterniflora (smooth cordgrass); infestation of densely packed plants. USA.
TitleHabit
CaptionSpartina alterniflora (smooth cordgrass); infestation of densely packed plants. USA.
Copyright©John M. Randall/The Nature Conservancy/Bugwood.org - CC BY-NC 3.0 US
Spartina alterniflora (smooth cordgrass); infestation of densely packed plants. USA.
HabitSpartina alterniflora (smooth cordgrass); infestation of densely packed plants. USA.©John M. Randall/The Nature Conservancy/Bugwood.org - CC BY-NC 3.0 US
Spartina alterniflora (smooth cordgrass); infestation of densely packed plants on a mudflat. USA.
TitleHabit
CaptionSpartina alterniflora (smooth cordgrass); infestation of densely packed plants on a mudflat. USA.
Copyright©John M. Randall/The Nature Conservancy/Bugwood.org - CC BY-NC 3.0 US
Spartina alterniflora (smooth cordgrass); infestation of densely packed plants on a mudflat. USA.
HabitSpartina alterniflora (smooth cordgrass); infestation of densely packed plants on a mudflat. USA.©John M. Randall/The Nature Conservancy/Bugwood.org - CC BY-NC 3.0 US
Spartina alterniflora (smooth cordgrass); infestation of densely packed plants, showing flower spikes. USA.
TitleHabit
CaptionSpartina alterniflora (smooth cordgrass); infestation of densely packed plants, showing flower spikes. USA.
Copyright©Fred Weinmann/Bugwood.org - CC BY-NC 3.0 US
Spartina alterniflora (smooth cordgrass); infestation of densely packed plants, showing flower spikes. USA.
HabitSpartina alterniflora (smooth cordgrass); infestation of densely packed plants, showing flower spikes. USA.©Fred Weinmann/Bugwood.org - CC BY-NC 3.0 US
Spartina alterniflora (smooth cordgrass); inflorescence. USA.
TitleInflorescence
CaptionSpartina alterniflora (smooth cordgrass); inflorescence. USA.
Copyright©Joseph M. DiTomaso/University of California-Davis/Bugwood.org - CC BY-NC 3.0 US
Spartina alterniflora (smooth cordgrass); inflorescence. USA.
InflorescenceSpartina alterniflora (smooth cordgrass); inflorescence. USA.©Joseph M. DiTomaso/University of California-Davis/Bugwood.org - CC BY-NC 3.0 US
Spartina alterniflora (smooth cordgrass); stem, showing collar and sheath. USA.
TitleStem
CaptionSpartina alterniflora (smooth cordgrass); stem, showing collar and sheath. USA.
Copyright©Joseph M. DiTomaso/University of California-Davis/Bugwood.org - CC BY-NC 3.0 US
Spartina alterniflora (smooth cordgrass); stem, showing collar and sheath. USA.
StemSpartina alterniflora (smooth cordgrass); stem, showing collar and sheath. USA.©Joseph M. DiTomaso/University of California-Davis/Bugwood.org - CC BY-NC 3.0 US

Identity

Top of page

Preferred Scientific Name

  • Spartina alterniflora Loisel

Preferred Common Name

  • smooth cordgrass

International Common Names

  • English: Atlantic cordgrass; saltmarsh cordgrass; salt-water cordgrass

Summary of Invasiveness

Top of page

S. alterniflora, along with other Spartina was initially seen by many coastal engineers as a species that could be used to create natural erosion control barriers. S. alterniflora is a rhizomatous perennial grass, grows 0.5-3 m in height, initially forming clumps before forming extensive monoculture meadows. Spartina spp. have a dense root/rhizome system that binds coastal mud and its sturdy stem decreases wave action allowing silt deposition, causing elevation of the mudbank, assisting in land reclamation. As a result, it was widely planted at coastal sites throughout the UK, Northern Europe, Australia, New Zealand, China and USA, where it has naturally colonized (via seed or vegetative fragments) large areas of tidal mudflats, becoming an invasive species. Natural habitats are altered to monoculture Spartina meadows, resulting in displacement of flora and fauna. Management of the S. alterniflora is expensive and time consuming, early prevention of invasion is recommended prior to its establishment.

Taxonomic Tree

Top of page
  • Domain: Eukaryota
  •     Kingdom: Plantae
  •         Phylum: Spermatophyta
  •             Subphylum: Angiospermae
  •                 Class: Monocotyledonae
  •                     Order: Cyperales
  •                         Family: Poaceae
  •                             Genus: Spartina
  •                                 Species: Spartina alterniflora

Notes on Taxonomy and Nomenclature

Top of page

Spartina is a relatively small genus consisting of approximately 14 species, geographically centered along the east coast of North and South America, with outliers on the west coast of North America, Europe, and Tristan da Cunha. Members of the genus occur primarily in wetlands, especially estuaries (Partridge, 1987).

Description

Top of page

S. alterniflora is a rhizomatous perennial grass that grows initially in round, genetically similar, clumps ranging between 0.5-3m in height, eventually forming extensive monoculture meadows. The stems are hollow and hairless. The leaf blades are 3 to 25 mm wide. The leaves lack auricles and have ligules (1-2 mm) that consist of a fringe of hairs. The flowers (classified yellow, although visually seem white) are inconspicuous and are borne in greatly congested spikes, 2-5 cm long (Hitchcock et al., 1969). Along its introduced east coast range S. alterniflora flowers between late August and September. The plant is deciduous; its stems die back at the end of each growing season (Ebasco Environmental, 1992; Daehler and Strong, 1994).

Within its native range of the Atlantic and Gulf coastlines of USA, S. alterniflora exhibits two growth forms, at different salt marsh zones. A tall form occurs along creek banks and drainage channels. Landward of the tall form, an intermediate form occurs, which grades into a stunted form at the salt marsh interior (Smart, 1982).

A detailed description of S. alterniflora is provided by the Grass Manual on the Web (http://herbarium.usu.edu/).

Plants rhizomatous; rhizomes elongate, flaccid, white, scales inflated, not or only slightly imbricate. Culms to 250 cm tall, (0.3) 5-15(20) mm thick, erect, solitary or in small clumps, succulent, glabrous, having an unpleasant, sulphurous odor when fresh. Sheaths mostly glabrous, throat glabrous or minutely pilose, lower sheaths often wrinkled; ligules 1-2 mm; blades to 60 cm long, 3-25 mm wide, lower blades shorter than those above, usually flat basally, becoming involute distally, abaxial surfaces glabrous, adaxial surfaces glabrous or sparsely pilose, margins usually smooth, sometimes slightly scabrous, apices attenuate. Panicles 10-40 cm, with 3-25 branches, often partially enclosed in the uppermost sheath; branches 5-15 cm, loosely appressed, not twisted, more or less equally subremote to moderately imbricate throughout the panicle, axes often prolonged beyond the distal spikelets, with 10-30 spikelets. Spikelets 8-14 mm, straight, usually divergent, more or less equally imbricate on all the branches. Glumes straight, sides usually glabrous, sometimes pilose near the base or appressed pubescent, hairs to 0.3 mm; lower glumes 4-10 mm, acute; upper glumes 8-14 mm, keels glabrous, lateral veins not present, apices acuminate to obtuse, occasionally apiculate; lemmas glabrous or sparsely pilose, apices usually acuminate; paleas slightly exceeding the lemmas, thin, papery, apices obtuse or rounded; anthers 3-6 mm. 2n = 62.

Plant Type

Top of page Grass / sedge
Vegetatively propagated

Distribution

Top of page

The native range of S. alterniflora is the Atlantic and Gulf Coasts of the United States. It forms the dominant salt-marsh community in salt water, normally forming monoculture meadows where conditions allow.

Distribution Table

Top of page

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

ChinaWidespreadIntroduced Invasive McEnnulty and et al., undated; Ding et al., 2008

North America

Canada
-British ColumbiaWidespreadIntroduced Invasive Kilbride et al., 1995
-Nova ScotiaWidespreadNative Invasive Cranford et al., 1989
USA
-CaliforniaPresentIntroduced Invasive Daehler and Strong, 1995; Daehler and Strong, 1996; Anttila and Daehler, 1997; Daehler and Strong, 1997; Grevstad et al., 2003; Ayres et al., 2004
-ConnecticutPresentNative Invasive Bertness et al., 1992; Chambers et al., 1998
-FloridaPresentNative Invasive Grevstad et al., 2003
-GeorgiaPresentNative Invasive Reimold et al., 1975; Turner, 1987; Goranson et al., 2004
-LouisianaPresentNative Invasive Linthurst, 1979; Mendelssohn and McKee, 1988; Lessman et al., 1997
-MainePresentNative Invasive Bertness et al., 1992
-MarylandPresentNative Invasive Furbish and Albano, 1994; Grevstad et al., 2003
-MassachusettsPresentNative Invasive Bertness et al., 1992
-MississippiPresentNative Invasive Lythe and Lythe, 1998; Brown et al., 2006
-New HampshirePresentNative Invasive Bertness et al., 1992
-North CarolinaPresentNative Invasive Linthurst, 1979
-OregonWidespreadIntroduced Invasive Daehler and Strong, 1996
-Rhode IslandPresentNative Invasive Bertness et al., 1992
-TexasPresentNative Invasive Goranson et al., 2004
-VirginiaPresentNative Invasive Furbish and Albano, 1994; Silliman and Zieman, 2001
-WashingtonPresentIntroduced Invasive Daehler and Strong, 1997; Harrington et al., 1997; Luiting et al., 1997; Thom et al., 1997; Cordell et al., 1998; Feist and Simenstad, 2000; Patten, 2002; Grevstad et al., 2003; Hedge et al., 2003; Major et al., 2003

South America

Brazil
-Rio Grande do SulPresentIntroduced Invasive Costa et al., 2003
UruguayPresentIntroduced Invasive Costa et al., 2003

Europe

FrancePresentIntroduced Invasive Weber, 2003
UKPresentIntroduced Invasive Mullins and Marks, 1987; Maskell and Raybould, 2001

Oceania

Australia
-South AustraliaWidespreadIntroduced Invasive McEnnulty and et al., undatedIn southern Australia, introduced rice grass species S. anglica, S. alterniflora and S. townsendii have been used to stabilise mud banks but are now considered a nuisance
-TasmaniaWidespreadIntroduced Invasive Hedge and Kriwoken, 1997; Hedge et al., 1997
-VictoriaWidespreadIntroduced Invasive Hedge and Kriwoken, 1997; Hedge et al., 1997
New ZealandWidespreadIntroduced Invasive Bascand, 1968; Bascand, 1970; Shaw and Gosling, 1997

History of Introduction and Spread

Top of page

The initial date and method of S. alterniflora introduction to the West (Pacific) coastline is disputed. Sayce (1988) suggests that S. alterniflora was introduced to Willapa Bay, WA, as a discarded packaging material for shipments of eastern oyster spats originating from the east coast of North America. Initially, the species established on the west side of Long Island (Sayce, 1988). However, Cohen and Carlton (1995) have suggested that the earliest report of S. alterniflora occurred around 1911, suggesting that solid ballast material is the most likely transport mechanism. Irrespective of the initial means of introduction, the plant was not accurately identified until 1940s, when the plants flowered (Scheffer, 1945; Sayce, 1988). The clumps, which covered several hectares at that time, had first been noted around 1911 (Scheffer, 1945). During the first 50 years, the population slowly expanded, but from 1945 to 1988 the plant became established throughout the bay, forming vast meadows (Sayce, 1988). After nearly a century of expansion the initial infestation in Willapa Bay spread to a maximum extent of 3500 hectares in 2003. Recent control methods, during 2005/6 have notably reduced the extent of the Willapa population (Murphy et al., 2007). In Puget Sound, WA, S. alterniflora was introduced to stabilize coastlines and increase the vegetative cover of mudflats to reduce wave impact. The Dike Island Gun Club planted S. alterniflora in Padilla Bay in the 1940s to stabilize an island in the south bay. S. alterniflora was also introduced to Thorndyke Bay, Kala Point, and Sequim Bay to increase vegetative cover (Ebasco Environmental, 1992).

In California, S. alterniflora is found at multiple sites in the San Francisco Bay, mostly concentrated in the southern part of the bay (Callaway and Josselyn, 1992; Cohen and Carlton, 1995). A small population was eradicated from Humbolt Bay. Also present in Bolinas Lagoon and the bays of Point Reyes National Seashore, north of San Francisco, where it is being smothered or dug out (Howard, 2008).

Non-indigenous populations of S. alterniflora are also documented in Australia, New Zealand, China, France, the Netherlands and United Kingdom.

Introductions

Top of page
Introduced toIntroduced fromYearReasonIntroduced byEstablished in wild throughReferencesNotes
Natural reproductionContinuous restocking
California 1970s Yes No Cohen and Carlton, 1995 Reason: wetland mitigation and shoreline stabilisation
Oregon 1970s Habitat restoration and improvement (pathway cause) No No Frenkel, 1990 Initially established, treated deemed eradicated in 1997
Washington 1894 Yes No Sayce, 1988
Washington 1907 Yes No Cohen and Carlton, 1995 Reason: solid ship ballast

Risk of Introduction

Top of page

S. alterniflora can spread via seed dispersal or vegetative fragments. This means that the introduction of S. alterniflora to an estuary or coastline can occur via either natural spread, due to tidal conditions or via human induced actions such as shipping (ballast water) or intentional planting (e.g. San Francisco Bay). S. alterniflora has also been reportedly used as a packing material for oyster shipments. Discarded material could have resulted in the initial invasion of this species from the east to west coast of United States of America (Sayce, 1988).


The risk of intentional introductions is now reduced as this species is now a regulated listed weed in most American states, New Zealand, Australia and United Kingdom.

Habitat

Top of page

S. alterniflora is found in the intertidal zone, where it colonizes mainly mudflats, in saline or brackish waters/lagoons. It prefers locations with low to moderate wave energy, where it further decreases the wave energy causing sediment to be deposited around its stems. S. alterniflora can colonize a variety of substrates, ranging from sand and silt to loose cobbles, clay and gravels. It also has the capacity to tolerate a wide range of environmental conditions, including: inundation up to approximately 12 hours a day, pH levels between 4.5and 8.5 and salinity levels of 10-60 ppt, although 10-20 ppt allows for optimal growth (Landin, 1991).


Within its native range, S. alterniflora dominates the low salt marsh forming extensive monoculture meadows, growing from 0.7m below mean sea level to mean high water (Bertness, 1991; Landin, 1991). Within its introduced range, specifically Willapa Bay, WA. S. alterniflora has been recorded as being present between 1.75 and 2.75 m above mean lower low water level (MLLW), it also occurs along the tidal range of rivers along the periphery of Willapa Bay (Sayce, 1988; Kunz and Martz, 1993).

Habitat List

Top of page
CategoryHabitatPresenceStatus
Littoral
Intertidal zone Principal habitat Harmful (pest or invasive)
Intertidal zone Principal habitat Natural
Mud flats Principal habitat Harmful (pest or invasive)
Salt marshes Principal habitat Harmful (pest or invasive)

Biology and Ecology

Top of page

Reproductive Biology

S. alterniflora is a long-lived perennial that can reproduce both sexually and by vegetative fragmentation. Daehler and Strong (1994) conducted a self-pollinating experiment to show that S. alterniflora outcrosses, with all self-pollinated seeds failing to germinate. Inflorescences, which are thought to be wind pollinated, develop in August through to October and typically consist of numerous spikelets. Each spikelet contains one seed (Moberley, 1956; Daehler and Strong, 1994). Dormant seeds do not survive longer than one year (Woodhouse, 1979). However, in several areas where the S. alterniflora has been introduced it does not produce seed. No flowers have been observed in New Zealand or in Padilla Bay, and reports on the Willapa Bay population show that it did not flower for almost 50 years after its introduction (Scheffer, 1945; Partridge, 1987; Riggs, 1992; Kunz and Martz, 1993). Low soil temperature can suppress or delay flowering period and reduce seed production in Spartina. Since the waters of the Washington coast are cooler than those in the species’ native Eastern American range, temperature may regulate flowering and seed production (Ebasco Environmental, 1992).

S. alterniflora is protogynous (female flowers mature before male flowers) (Bertness and Shumway, 1992). This strategy helps ensure outcrossing. Since the S. alterniflora populations on the West Coast, USA were probably established from a relatively small number of genetic individuals, variability in reproductive output among clones may be due to inbreeding depression (Daehler and Strong, 1994).

Associations

S. alterniflora is the larval host and/or the nectar source of Automeris louisiana (Louisianan eyed silk moth) (Covell, 2005).

Climate

Top of page
ClimateStatusDescriptionRemark
Cf - Warm temperate climate, wet all year Tolerated Warm average temp. > 10°C, Cold average temp. > 0°C, wet all year
Cs - Warm temperate climate with dry summer Preferred Warm average temp. > 10°C, Cold average temp. > 0°C, dry summers
Cw - Warm temperate climate with dry winter Tolerated Warm temperate climate with dry winter (Warm average temp. > 10°C, Cold average temp. > 0°C, dry winters)

Latitude/Altitude Ranges

Top of page
Latitude North (°N)Latitude South (°S)Altitude Lower (m)Altitude Upper (m)
59.04265 -46.60768 0 0

Soil Tolerances

Top of page

Soil drainage

  • free
  • impeded

Soil reaction

  • acid
  • alkaline
  • neutral

Soil texture

  • light

Special soil tolerances

  • infertile
  • saline

Natural enemies

Top of page
Natural enemyTypeLife stagesSpecificityReferencesBiological control inBiological control on
Prokelisia marginata Herbivore Leaves to genus Grevstad et al., 2003 Potential is being tested in the lab and the field

Pathway Causes

Top of page
CauseNotesLong DistanceLocalReferences
Habitat restoration and improvementUsed to stabilise coastlines and as what was thought to be a potential land reclamation tool Yes Yes Cohen and Carlton, 1995; Hedge et al., 2003
Self-propelledSpreads along the American coastline via seed and rhizomes Yes Simenstad and Thom, 1995

Pathway Vectors

Top of page
VectorNotesLong DistanceLocalReferences
Containers and packaging - non-woodPotentially introduced to Washington state as discarded packaging material for shipments of oysters. Yes Yes Cohen and Carlton, 1995
Floating vegetation and debrisSeeds and rhizomes spread via spring and winter tides. Yes Yes Simenstad and Thom, 1995
Ship ballast water and sedimentBoth seeds and small pieces of rhizomes could be transported via ship ballast. Yes Yes Cohen and Carlton, 1995

Impact Summary

Top of page
CategoryImpact
Environment (generally) Negative

Environmental Impact

Top of page

Impact on Habitats 

Within its introduced range a concern is being raised over S. alterniflora impact to habitats where present due to its ability to reduce tidal energy and trap sediment. On the East and Gulf native coastal ranges, where S. alterniflora is a major component of salt marsh vegetation, wave energy is high, however the presence of S. alterniflora allows for sediment accretion rates of 13 mm/year, with higher stem densities resulting in higher sediment deposition rates and steeper beach profiles (Gleason et al., 1979; Simenstad and Thom, 1995). Where S. alterniflora has been introduced to San Francisco Bay, sediment accretion rates have been estimated at 1.4 to 13.3 mm/yr. (Callaway, 1990; Josselyn et al., 1993; Simenstad and Thom, 1995). In contrast, a study of low intertidal salt marshes in Washington and Oregon that lacked S. alterniflora found that the sediment accretion rate ranged from 2.3 to 6.6 mm/year, with a mean of 3.6 mm/year. (Thom, 1992). This higher rate of accretion rate associated with Spartina may change the fundamental nature of portions of Washington’s coastline. Before S. alterniflora was present, Pacific Northwest estuaries consisted of bare, gently sloping mud flats with shallow tidal channels. Fully developed Spartina marshes have steeply sloping seaward edges and deep, steep-sided tidal channels. S. alterniflora clones trap sediment, causing the clones to rise above the surrounding mudflats (Ebasco Environmental, 1992). Higher stem densities dissipate more wave action, therefore allowing a larger amount of sediment to be deposited and a steeper beach profile to form (Gleason et al., 1979).

Another impact of increased sediment accretion is the resultant change in water circulation patterns. Using a close relative of S. alterniflora as a guide, sediment accretion associated with S. anglica infestations in England, has been reported to reduce tidal flow (Hubbard, 1965). In addition, if large, dense populations of S. alterniflora are present around the mouth of an estuary, decreased flow may occur, leading to an increase in flooding likelihood, especially during sustained periods of heavy rainfall coinciding within above average tides (Ebasco Environmental, 1993).

Impact on Biodiversity

The spread of S. alterniflora can impact the native flora and fauna of the intertidal zone. Spartina may displace native plants, such as Zosteramarina (seagrass), Salicornia virginica, Triglochin maritimum, Jaumea carnosa, and Fucus distichus (Wiggins and Binney, 1987; Simenstad and Thom, 1995). Displacement of several of these plants is of particular concern. For example, seagrasses (Zostera spp.), provides important refuges and food sources for fish, crabs, waterfowl, and other marine life (Balthuis and Scott, 1993).

Other concerns include the replacement of open mudflat habitats associated with bottom-dwelling invertebrate communities by vegetative salt marsh species. Experimental evidence indicates that invertebrate populations in the sediments of S. alterniflora clones, in Willapa Bay are smaller than populations in surrounding non-vegetated intertidal mudflats (Norman and Patten, 1994). The loss of habitat for bivalves is of particular concern in Willapa Bay, WA, as it supports a US$16 million oyster industry. Waders and waterfowl will lose important foraging and refuge habitat. In Willapa National Wildlife Refuge, S. alterniflora has already displaced an estimated 16-20 percent of critical habitat for wintering and breeding aquatic birds (Foss, 1992).

Risk and Impact Factors

Top of page

Impact mechanisms

  • Competition - monopolizing resources
  • Competition - shading
  • Competition - smothering
  • Hybridization
  • Pollen swamping
  • Rapid growth
  • Rooting

Impact outcomes

  • Damaged ecosystem services
  • Ecosystem change/ habitat alteration
  • Modification of hydrology
  • Modification of natural benthic communities
  • Modification of nutrient regime
  • Modification of successional patterns
  • Monoculture formation
  • Negatively impacts agriculture
  • Negatively impacts aquaculture/fisheries
  • Negatively impacts cultural/traditional practices
  • Negatively impacts livelihoods
  • Negatively impacts tourism
  • Reduced amenity values
  • Reduced native biodiversity
  • Soil accretion
  • Threat to/ loss of native species
  • Transportation disruption

Invasiveness

  • Abundant in its native range
  • Benefits from human association (i.e. it is a human commensal)
  • Fast growing
  • Has a broad native range
  • Has high reproductive potential
  • Has propagules that can remain viable for more than one year
  • Highly adaptable to different environments
  • Invasive in its native range
  • Is a habitat generalist
  • Long lived
  • Pioneering in disturbed areas
  • Proved invasive outside its native range
  • Reproduces asexually
  • Tolerates, or benefits from, cultivation, browsing pressure, mutilation, fire etc

Likelihood of entry/control

  • Difficult/costly to control
  • Highly likely to be transported internationally accidentally

Uses

Top of page

In its native habitat, S. alterniflora is of great value (Landin, 1991; Simenstad and Thom, 1995). The species is extremely productive, exporting approximately 1300 g/m2 of detritus annually to the estuarine system (Landin, 1991). Within its native range, S. alterniflora became highly regarded as an erosion control tool, which led to it being widely introduced to other areas (Simenstad and Thom, 1995). Within its native habitat, S. alterniflora roots and shoots are a food source for waterfowl and wetland mammals, partly keeping the expansion of Spartina wetlands in check. In addition, stands of S. alterniflora can serve as a nursery area for mangroves, and estuarine fish and shellfish.

Because of their ability to trap sediment via decreasing wave energy, Spartina species have been introduced to many parts of the world for estuary reclamation and for erosion control (Partridge, 1987). Normally S. anglica has been used for this purpose, however, S. alterniflora has been planted in some areas, such as the North Island of New Zealand (Partridge, 1987).

There are also some economically beneficial uses for S. alterniflora. The species is palatable to livestock, especially deer and horses, so the plant’s continued spread may increase available pasture. S. alterniflora has also been investigated for use within the paper production industry (Ebasco Environmental, 1993).

Uses List

Top of page

Animal feed, fodder, forage

  • Fodder/animal feed

Environmental

  • Erosion control or dune stabilization
  • Land reclamation

Prevention and Control

Top of page

Control 

Roberts and Pullin (2006; 2007) have, using systematic review and meta-analysis, extensively reviewed the efficacy of the control methods available for S. alterniflora. Within the appendix of their 2006 report, they summarise the individual results of each disparate study and combine these within a meta-analysis to establish the most efficacy control method and attempt to obtain variables (e.g. inundation time, substrate) that might affect the outcomes of each control method. The table below shows the average S. alterniflora density reductions achieved by various control methods. 

The effectiveness of control methods at reducing the densities of S. alterniflora (Roberts and Pullin, 2006)

 

Control Method
Effectiveness against S. alterniflora
(-% = increase in densities, +% = reduction in densities)
Tilling (mechanical)
96.5%
Cut & glyphosate
91.1%
Crushing (2+ treatment) (mechanical)
91.0%
Disking (mechanical)
89.5%
Imazapyr (herbicide)
85.1%
Crush & glyphosate
77.9%
Cut only (mechanical)
68.1%
Crushing (single treatment) (mechanical)
61.2%
Fenuron (herbicide)
58.0%
Glyphosate (herbicide)
57.9%
Paraquat (herbicide)
52.7%
2,2-DPA (herbicide)
50.5%
Aminote-T (herbicide)
38.9%
Ungulates (herbivores e.g. deer/horses)
24.4%
Prokelisia spp. (natural enemy)
18.4%
Diuron (herbicide)
1.4%

 

Physical/mechanical control

On a small scale seedlings can be pulled out. Care must be taken to remove both the shoot and root for effective control. However, seedlings generally begin to tiller late in their first session. Once tillered, hand-pulling may break off portions of the root, allowing the plant to re-grow. Repeated hand-pulling of small plants will eventually result in their death (Spartina Task Force, 1994).

Cutting alone is an effective control intervention of S. alterniflora, producing, on average, an overall decease in stem density of 68.1%. In addition, when a cutting treatment is combined with application of glyphosate (after cutting), S. alterniflora control is vastly improved to 91.1% (Roberts and Pullin, 2006). No experimental trials of combining cutting and smothering are reported for control of S. alterniflora. which proved to be a highly effective control against another cordgrass species S. anglica, achieving around 98%.

Mechanical control interventions against S. alterniflora have been extensively trailed by Dr. Kim Patten on the Willapa Bay populations. Winter tilling produced the most effective control intervention, followed by disking and finally crushing. Crushing effectiveness was affected by the substrate type, with greatest control achieved on sand and soft silt, and least effective on firm silts or those areas with well established Spartina meadows. Based on bird usage and sediment softness, tilling appears to restore mudflats back to suitable habitat for foraging shoreline birds (Gross-Custard and Moser, 1988).

Unfortunately, tilling might be considered too costly for most Spartina management programmes, with the purchase of an amphibious tiller (around £150,000), and is slow to implement (approximately 0.25 ha/hr reported by Patten (2004). Crushing is less expensive than (approximately £50,000), and in addition is quicker than tilling (1-2hr/ha), but for more effective control two or more treatments are required in one year (Roberts and Pullin, 2006; 2007).

Movement control

The movement of Spartina is prohibited in most states of USA. It is also a notified weed, with legislation controlling its movement and planting in New Zealand, Australia, France and the Netherlands. 

Biological control

The use of Prokelisia spp. was shown to be an ineffective sole biological control agent against S. alterniflora, achieving a density reduction in stems of 18.4%. However, further investigation is required to see if integrating it with another control measure would increase its efficacy of controlling S. alterniflora.

Chemical control

The majority of trials captured by Roberts and Pullin (2006) review of Spartina control investigated the impact of either glyphosate or imazapyr. Limited numbers of trials were available for Fenuron, Paraquat, 2,2-DPA and Diuron. The density reductions achieved by the herbicides are included in the table of control measures.

From all the data captured for herbicide application, imazapyr, had the greatest impact in chemically controlling S. alterniflora densities (85% density decline). Lowerconcentrations of the herbicides active ingredient (ae) (1.7kg ae/ha) were required to achieve superior densityreductions than treating with glyphosate (38kg ae/ha). The addition of a surfactant/wetting agentincreased the imazapyr effectiveness at binding to the Spartina stands (Patten, 2002; Roberts and Pullin, 2006).

Control of S. alterniflora densities with glyphosate gave a combined density reduction of around 59%. Roberts and Pullin (2006) results showed there was a great deal of inconsistency (heterogeneity) within the datasets included in their meta-analysis. Further investigation of the differing methods of application used to apply glyphosate showed that aerial application did not significantly reduce the density of S. alterniflora. However, ground sprayed glyphosate did significantly reduce S. alterniflora density, with treatment dates of June/July applications of 38 kg ae/ha being more effective than either similar concentrations at different times of the year or lower active ingredient concentrations. Multiple years of application only marginally increased the herbicides effectiveness, however if a years application is missed then reduction in density drops below 50%. The use of 1-5% wetter or surfactant with the glyphosate application improved the impact of treatment (Norman and Patten, 1995; Patten, 2002; Roberts and Pullin, 2006).

Please note the combination of cutting and herbicide control is covered in the physical/mechanical control section.

Gaps in Knowledge/Research Needs

Top of page

Further investigation is required to establish the efficacy of the herbicides fenuron, Paraquat™, 2,2-DPA and diuron against S. alterniflora prior to their recommendation for widespread use. In addition the use of Prokelisia spp. could be investigated further as part of an integrated control programme.

References

Top of page

Anttila CK, Daehler CC, 1997. Pollen swamping of the native California cordgrass (S. Foliosa) by introduced smooth cordgrass (S. Alterniflora) in San Francisco Bay. In: The Proceedings of the Second International Spartina Conference, Olympia WA.

Ayres DR, Smith DL, Zaremba K, Klohr S, Strong DR, 2004. Spread of exotic cordgrasses and hybrids (Spartina spp.) in the tidal marshes of San Francisco Bay, California, USA. Biological Invasions, 6:221-231.

Balthuis DA, Scott BA, 1993. Effects of application of glyphosate on cordgrass, Spartina alterniflora, and adjacent native salt marsh vegetation in Padilla Bay, Washington. Padilla Bay National Estuarine Research Reserve Technical Report. Mount Vernon, Washington, USA: Washington State Department of Ecology.

Bascand LD, 1968. The control of Spartina species. In: Proceedings 21st N.Z. Weed Pest Control Conf, 108-13.

Bascand LD, 1970. The roles of Spartina species in New Zealand. Proceedings of the New Zealand Ecological Society, 17:33-40.

Bertness MD, 1991. Zonation of Spartina patens and Spartina alterniflora in a New England salt marsh. Ecology, 72(1):138-148.

Bertness MD, Gough L, Shumway SW, 1992. Salt Tolerances and the Distribution of Fugitive Salt Marsh Plants. Ecology, 73(5):1842-1851.

Bertness MD, Shumway SW, 1992. Consumer driven pollen limitation of seed production in marsh grasses. American Journal of Botany, 79(3):288-293.

Brown CE, Pezeshki SR, DeLaune RD, 2006. The effects of salinity and soil drying on nutrient uptake and growth of Spartina alterniflora in a simulated tidal system. Environmental and Experimental Botany, 58(1/3):140-148. http://www.sciencedirect.com/science/journal/00988472

Callaway JC, 1990. M.A. Thesis. San Francisco, CA, USA: San Francisco State University.

Callaway JC, Josselyn MN, 1992. The introduction and spread of smooth cordgrass (Spartina alterniflora) in South San Francisco Bay. Estuaries, 15(2):218-226.

Chambers RM, Mozder TJ, Ambrose JC, 1998. Effect of salinity and sulfide on the distribution of Phragmites australis and Spartina alterniflora in a tidal saltmarsh. Aquatic Botany, 62:161-169.

Cohen AN, Carlton JT, 1995. Nonindigenous Aquatic Species in a United States Estuary: A Case Study of the Biological Invasion of the San Francisco Bay and Delta. Report for the US Fish and Wildlife Service, Washington D.C. and the National Sea Grant College Program, Connecticut Sea Grant.

Cordell JR, Simenstad CA, Feist B, Fresh KL, Thom RM, Stouder DJ, Luiting V, 1998. The 8th International Zebra Mussel & Other Nuisance Species Conference, Sacramento, California.

Costa CSB, Marangoni JC, Azevedo AMG, 2003. Plant zonation in irregularly flooded salt marshes: relative importance of stress tolerance and biological interactions. Journal of Ecology (Oxford), 91(6):951-965.

Covell CV, 2005. A Field Guide to Moths of Eastern North America. Martinsville, VA, USA: Virginia Museum of Natural History.

Cranford PJ, Gordon DC, Jarvis CM, 1989. Measurement of cordgrass, Spartina alterniflora, production in a macrotidal estuary, Bay of Fundy. Estuaries, 12(1):27-34.

Daehler CC, Strong DR, 1994. Variable reproductive output among clones of Spartina alterniflora (Poaceae) invading San Francisco Bay, California: the influence of herbivory, pollination, and establishment site. American Journal of Botany, 81(3):307-313.

Daehler CC, Strong DR, 1995. Impact of high herbivore densities on introduced smooth cordgrass, Spartina alterniflora, invading San Francisco Bay, California. Estuaries, 18(2):409-417.

Daehler CC, Strong DR, 1996. Status, prediction and prevention of introduced cordgrass Spartina spp. invasions in Pacific estuaries, USA. In: Biological Conservation [ed. by Carey JR, Moyle P, Rejmánek M, Vermeij GJ], 51-58.

Daehler CC, Strong DR, 1997. Reduced herbivore resistance in introduced smooth cordgrass (Spartina alterniflora) after a century of herbivore-free growth. Oecologia, 110(1):99-108.

Ding JianQing, Mack RN, Lu Ping, Ren MingXun, Huang HongWen, 2008. China's booming economy is sparking and accelerating biological invasions. BioScience, 58(4):317-324. http://www.bioone.org/perlserv/?request=get-current-issue

Ebasco Environmental, 1992. Noxious emergent plant environmental impact statement. element A - Spartina: distribution, biology, and ecology. Final Report, submitted to Washington State Department of Ecology, Olympia.

Ebasco Environmental, 1993. Noxious emergent plant environmental impact statement. element c - no action: efficacy and impacts. Final Report, submitted to Washington State Department of Ecology, Olympia.

Feist BE, Simenstad CA, 2000. Expansion rates and recruitment frequency of exotic smooth cordgrass, Spartina alterniflora (Loisel), colonizing unvegetated littoral flats in Willapa Bay, Washington. Estuaries, 23:267-274.

Foss S, 1992. Spartina: Threat to Washington's saltwater habitat. Washington State Department of Agriculture Bulletin.

Frenkel RE, 1990. Spartina in Oregon. In: Mumford TF, Peyton P, Sayce JR, Harbell S, eds. Spartina Workshop Record, Washington Sea Grant Program, University of Washington, Seattle, pp. 26.

Furbish CE, Albano M, 1994. Selective herbivory and plant community structure in a mid-Atlantic salt marsh. Ecology, 75(4):1015-1022.

Gleason ML, Elmer DA, Pien NC, Fisher JS, 1979. Effects of stem density upon sediment retention by salt marsh cord grass, Spartina alterniflora Loisel. Estuaries, 2:271-273.

Goranson CE, Ho C-K, Pennings SC, 2004. Environmental gradients and herbivores feeding preferences in coastal salt marshes. Oecologia, 140:591-600.

Goss-Custard JD, Moser ME, 1988. Rates of change in the numbers of dunlin, Calidris alpina, wintering in British estuaries in relation to the spread of Spartina anglica. Journal of Applied Ecology, 25:95-109.

Grevstad FS, Strong DR, Garcia-Rossi D, Switzer RW, Wecker MS, 2003. Biological control of Spartina alterniflora in Willapa Bay, Washington using the planthopper Prokelisia marginata: agent specificity and early results. Biological Control, 27(1):32-42.

Harrington JA, Harrington LMB, Berlin CJ, 1997. Modelling Spartina in Willipa Bay. In: The Proceedings of the Second International Spartina Conference, Olympia WA.

Hedge P, Kriwoken L, 1997. Managing Spartina in Victoria and Tasmania, Australia. In: The Proceedings of the Second International Spartina Conference, Olympia WA.

Hedge P, Kriwoken L, Ritar A, 1997. The distribution of Spartina in Victoria and Tasmania, Australia. In: The Proceedings of the Second International Spartina Conference, Olympia WA.

Hedge P, Kriwoken LK, Patten K, 2003. A review of Spartina management in Washington State, US. Journal of Aquatic Plant Management, 41:82-90.

Hitchcock CL, Cronquist A, Own-Bey M, 1969. Vascular plants of the Pacific Northwest. Part 1. Vascular cryptogams, gymnosperms and monocotyledons. Vascular plants of the Pacific Northwest. Part 1. Vascular cryptogams, gymnosperms and monocotyledons. Seattle: University of Washington Press.

Howard V, 2008. Spartina alterniflora. USGS Nonindigenous Aquatic Species Database. Gainesville, FL, USA.

Hubbard JCE, 1965. Spartina marshes in southern England. 6. Pattern of invasion in Poole Harbour. Journal of Ecology, S3(3):799-813.

Josselyn M, Larsson B, Fiorillo A, 1993. An ecological comparison of an introduced marsh plant, Spartina alterniflora, with its native congener, Spartina foliosa, in San Francisco Bay. Gaps in Knowledge Res. Prog., San Francisco Bay Estuary Proj. Tiburon, CA, USA: Romberg Tiburon Centers, San Francisco State University, 47 pp.

Kilbride KM, Paveglio FL, Grue CE, 1995. Control of smooth cordgrass with Rodeo® in a southwestern Washington estuary. Wildlife Society Bulletin, 23(3):520-524.

Kunz K, Martz M, 1993. Characterization of exotic Spartina communities in Washington State. Appendix K - Emergent Noxious Weed Control Final Reports, Unpublished Report to Washington Department of Ecology, Olympia.

Landin MC, 1991. Growth habits and other considerations of smooth cordgrass, Spartina alterniflora Loisel. In: Spartina Workshop Record, Washington Sea Grant Program, University of Washington, Seattle [ed. by Mumford TF, Peyton P, Sayce JR, Harbell S], 15-20.

Lessman JM, Mendelssohn IA, Hester MW, McKee KL, 1997. Population variation in growth response to flooding of three marsh grasses. Ecological Engineering, 8:31-47.

Linthurst RA, 1979. The effects of aeration on the growth of Spartina alterniflora, Loisel. American Journal of Botany, 66(6):685-691.

Luiting VT, Cordell JR, Olson AM, Simenstad CA, 1997. Does exotic Spartina alterniflora change benthic invertebrate assemblages? In: The Proceedings of the Second International Spartina Conference, Olympia WA, 20-21 March 1997.

Lythe JS, Lythe TF, 1998. Altrazine effects on estuarine macrophytes Spartina alterniflora and Juncus roemerianus. Environmental Toxicology & Chemistry, 17(10):1972-1978.

Major WW, Grue CE, Grassley JM, Conquest LL, 2003. Mechanical and chemical control of smooth cordgrass in Willapa Bay, Washington. Journal of Aquatic Plant Management, 41:6-12.

Maskell LC, Raybould AF, 2001. The decline of Spartina alterniflora (Poaceae) in the British Isles. Watsonia, 23(3):391-400.

McEnnulty FR, Bax NJ, Britta S, Campbell ML, undated. A literature review of rapid response options for the control of ABWMAC listed species and related taxa in Australia. CSIRO Marine Research: Centre for Research on Introduced Marine Pests.

Mendelssohn IA, McKee KL, 1988. Spartina alterniflora Die-back in Louisianna: Time-course Investigation of Soil Waterlogging Effects. Journal of Ecology, 76:509-521.

Moberley DG, 1956. Taxonomy and distribution of the genus Spartina. Iowa State Journal of Science, 30:471-574.

Mullins PH, Marks TC, 1987. Flowering phenology and seed production of Spartina anglica. Journal of Ecology, UK, 75(4):1037-1048.

Murphy KC, Taylor RR, Philips CH, 2007. Progress of the 2006 Spartina eradication program. Olympia, Washington, USA: Washington State Department of Agriculture. http://agr.gov/PlantInsects/Weeds/Spartina/docs/SpartinaReport2006.pdf

Norman M, Patten K, 1994. Optimizing the efficacy of glyphosate to control Spartina alterniflora. Unpublished progress report submitted to WSDNR (January-May 1994).

Norman M, Patten K, 1995. Evaluation of mechanical methods and herbicide adjuvant treatments for the effective control of Spartina spp. Unpublished report on file at Washington State University Long Beach Research and Extension Unit, Long Beach, Washington.

Partridge TR, 1987. Spartina in New Zealand. New Zealand Journal of Botany, 25(4):567-575.

Patten K, 2002. Smooth cordgrass (Spartina alterniflora) control with imazapyr. Weed Technology, 16(4):826-832.

Patten K, 2004. Comparison of chemical and mechanical control efforts for invasive Spartina in Willapa Bay, WA. Unpublished Report available via author contact.

Reimold RJ, Linthurst RA, Wolf PL, 1975. Effects of grazing on a salt marsh. Biological Conservation, 8:105-125.

Riggs SR, 1992. Distribution of Spartina alterniflora in Padilla Bay, Washington, in 1991. Washington State Department of Ecology, Padilla Bay National Estuarine Research Reserve Technical Report No. 3. Mount Vernon, Washington, USA, 63 pp.

Roberts PD, Pullin AS, 2006. The effectiveness of management options used for the control of Spartina species. Systematic Review No. 22. Birmingham, UK: Centre for Evidence- Based Conservation.

Roberts PD, Pullin AS, 2007. The effectiveness of management interventions for the control of Spartina species: a systematic review and meta-analysis. Aquatic Conservation Marine and Freshwater Ecosystems, 18(5):592-618.

Sayce K, 1988. Introduced Cordgrass, Spartina alterniflora Losiel. in Saltmarshes and Tidelands of Willapa Bay, Washington. Report to the US Fish and Wildlife Service, Willapa National Wildlife Refuge.

Scheffer TH, 1945. The introduction of Spartina alterniflora to Washington with oyster culture. Leaflets of Western Botany, 4:163-164.

Shaw WB, Gosling DS, 1997. Spartina ecology, control and eradication - recent New Zealand experience. In: The Proceedings of the Second International Spartina Conference, Olympia WA.

Silliman BR, Zieman JC, 2001. Top-down control of Spartina alterniflora production by periwinkle grazing in a Virginia salt marsh. Ecology, 82(10):2830-2845. http://www.esajournals.org/esaonline/?request=get-abstract&issn=0012-9658&volume=082&issue=10&page=2830

Simenstad CA, Thom RM, 1995. Spartina alterniflora (Smooth Cordgrass) as an Invasive Halophyte in Pacific Northwest Estuaries. Hortus Northwest, 6(1):9-40.

Smart RM, 1982. Distribution and environmental control of productivity and growth form of Spartina alterniflora (Loisel.). Contributions to the ecology of halophytes [ed. by Sen DN, Rajpurohit KS]. The Hague, Netherlands: Dr. W. Junk Publishers, 127-142.

Spartina Task Force, 1994. Spartina management program: Intergrated weed management for private lands in Willapa Bay, prepared for the Noxious Weed Board and County Commissioners, Pacific County, Washington.

Thom R, Cordell J, Simenstad C, Luiting V, Borde B, 1997. Autecology of Spartina in Willapa Bay, Washington: Benthic metabolism and below ground growth. In: The Proceedings of the Second International Spartina Conference, Olympia WA.

Thom RM, 1992. Accretion rates of low intertidal salt marshes in the Pacific Northwest. Wetlands, 12:147-156.

Turner MG, 1987. Effects of grazing by feral horses, clipping, trampling and burning in a Georgia salt marsh. Estuaries, 10(1):54-60.

Weber E, 2003. Invasive plant species of the world: A reference guide to environmental weeds. Wallingford, UK: CAB International, 548 pp.

Wiggins J, Binney E, 1987. A baseline study of the distribution of Spartina alterniflora in Padilla Bay. Report to Washington Dept. Ecology, Padilla Bay National Estuarine Research Reserve. Padilla Bay National Estuarine Research Reserve Reprint Series No. 7., 28 pp.

Woodhouse WW, 1979. Building saltmarshes along the coasts of the continental United States. Special report No. 4. Belvoir, VA, USA: U.S. Army Corps of Engineers, Coastal Engineering Research Center.

Contributors

Top of page

12/05/08 Original text by:

Philip Roberts, CABI, Nosworthy Way, Wallingford, Oxon OX10 8DE, UK

Distribution Maps

Top of page
You can pan and zoom the map
Save map