European and Mediterranean Plant Protection Organization
Organisation Européenne et Méditerranéenne pour la Protection des Plantes
Data sheets on invasive alien plants
Fiches informatives sur les plantes exotiques envahissantes
06-12971
P IAS Point 10.1
Cabomba caroliniana
Identity
Scientific name: Cabomba caroliniana
Taxonomic position: Cabombaceae
Synonyms: Cabomba australis, Cabomba pulcherrima (R.M. Harper) Fassett (Nomenclatural and
Specimen Database of the Missouri Botanical Garden).
Common names: Carolina fanwort, Gray fanwort, Purple cabomba, Washington grass, Carolina
water-shield, fish grass (English), Haarnixenkraut, Carolina (German), Cabomba de Caroline
(French).
EPPO code: CABCA
Phytosanitary categorization: EPPO A2 List of invasive alien plants
Morphology
Plant type
C. caroliniana is a fully submerged, perennial freshwater plant. Occasionally, leaves and flowers
grow above the water’s surface.
Description
Branched stems grow up to 10 m long and young stems have white or reddish-brown hairs.
Underwater leaves are divided into fine branches approximately 5 cm across, giving the plant its
characteristic feathery, fan-like appearance. Its delicate, fan-like fronds make it popular for aquaria.
These leaves secrete a sticky mucous which covers the submerged parts of the plant. Floating leaves
are small, diamond-shaped, entire, and occur on the flowering branches. The solitary flowers (< 2
cm across) emerge on stalks from the tips of the stems (Preconic Estuary Program) with 3 sepals and
petals, 3-6 stamens (PIER Species Info). They are white or pale yellow and may also include a pink
or purplish tinge. The fruit is coriaceous, indehiscent, about 3-seeded (Britton & Brown, 1913). On
the basis of flower colour, three subspecies or varieties of C. caroliniana are now distinguished
(Ørgaard, 1991): C. caroliniana var. caroliniana (white flowers) (= Cabomba australis Speg.,), C.
caroliniana. var pulcherrima R.M. Harper (purple flowers) (= Cabomba pulcherrima (R.M. Harper)
Fassett) and C. caroliniana var. flavida Ørgaard (yellow flowers). Several cultivars are grown and
used in the aquarium trade. No hybrids have been reported in the genus Cabomba, although it is
possible they could occur (Ørgaard, 1991; Mackey and Swarbrick, 1997).
Similarities to other species
C. caroliniana may be easily confused with other aquatic species. Identification is difficult because
it grows fully submerged. Another introduced species, the closely related pink cabomba (Cabomba
furcata) is also sold as an aquarium plant. It is pink in colour with purple flowers and is not
considered a weed by the Global Compendium of Weeds. The genus Cabomba consists of many
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closely related species, most of which are tropical in distribution. Other aquatic aquarium plants that
may be confused with Cabomba are Ceratophyllum spp. and Myriophyllum spp. and are also
considered weeds (Australian Department of the Environment and Heritage, 2003). In North
America, it has also often been confused with the native Ranunculus spp. and Megalodonta beckii
(Commonwealth of Massachusetts).
Biology and ecology
General
C. caroliniana grows quickly and produces a large amount of plant material. In Lake Macdonald in
Queensland, growth of 50 mm a day has been reported, allowing the plant to respond to wide
fluctuations in water depth. The fibrous roots grow on the substrate at the bottom of the water and the
stems can reach the surface. Floating parts of the plant can survive in water for 6 to 8 weeks
(Australian Department of the Environment and Heritage, 2003). It spreads via rhizomes or from
vegetative reproduction by stem fragments. A detached piece of the plant can regenerate into a full
plant as long as it has at least one pair of leaves, and pieces as short as 10 mm may be viable. In late
summer, C. caroliniana stems become brittle, and plants tend to break apart, creating opportunities
for spread (University of Maine Cooperative Extension). Wilson et al. (2001) record that in colder
climates both rooted stems and broken plant fragments lie prostrate on the lake bottom throughout
the winter and remain green under snow and ice. These regrow the following year and in this way the
plants are able to multiply.
In north-eastern North America, viable seeds do not seem to be produced. In the south-eastern NorthAmerica, seeds are formed and C. caroliniana can re-grow from seeds remaining in lake or pond
sediments (Commonwealth of Massachusetts).
In Australia, seeds or fruits have been found (P Champion, pers. comm.). In tropical areas, growth
and flowering are continuous. In temperate areas, flowering and maximum growth occur in summer.
The plant dies back in winter and lies on the bottom of the water body, where the stems break up and
provide dispersal material. New growth starts from these dislodged stem pieces (Australian
Department of the Environment and Heritage, 2003).
Habitats
C. caroliniana is a very hardy and persistent species that has established itself in a wide range of
aquatic habitats. It grows in the mud of slow flowing or stagnant freshwaters. It grows in streams,
small rivers, ponds, lakes, reservoirs, sloughs, ditches and canals.
Environmental requirements
It is sensitive to drying out and requires permanent contact with water, although it can survive wide
fluctuations in water depths. It is usually found is less than 3 m deep, but can manage to survive in
water up to 10 m deep. It grows well on a silty bed but not so well on hard surfaces. It grows better in
nutrient-rich waters with low pH, and tends to loose its leaves in more alkaline waters. High calcium
levels also inhibit growth. C. caroliniana has the unusual ability to grow in turbid or cloudy waters
(Australian Department of the Environment and Heritage, 2003). It does well both in cool and warm
waters.
Climatic and vegetational categorization
It requires direct sunlight. It prefers a warm climate with a temperature range of 13-27°C but can
survive when the surface of the water body is frozen. In Australia, prolonged snow cover is said to be
detrimental to Cabomba (Australian Department of the Environment and Heritage, 2003), while in
Canada, the plant overwinters under prolonged snow and ice cover and continues to thrive and
spread (C Wilson, pers. com.). Despite its tropical origins, the plants are capable of overwintering in
Canada and survive under snow and ice. As it has spread in the US and in Canada, it has shown its
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ability to thrive well outside the range of the warm, humid climates it is said to prefer in the
literature, to areas with “rain throughout the year and an average temperature of 15-18°C” (Mackey
& Swarbrick, 1997; Wilson, 2001).
Natural enemies
In its native habitat, C. caroliniana is eaten by waterfowl and some fish and provides cover for some
small fish and plankton (Ørgaard, 1991). Only recently have there been attempts to investigate
natural enemies of Cabomba in its native habitat (Cabrera Walsh and Julien, 2005). Some species of
weevils and noctuid Lepidoptera were found to feed significantly on plant material of Cabomba.
Geographical distribution
EPPO Region: Belgium, Hungary, the Netherlands, the United Kingdom (introduced into England).
Asia: China, India, Malaysia, Japan.
Oceania: Australia (New South Wales, Northern Territory (Invasive), Queensland (Invasive),
Victoria), New Caledonia, New Guinea.
North America (native except in the North-East and in the West): USA (Alabama, Arkansas,
California (invasive non-native), Connecticut (invasive non-native), Delaware, District of Columbia,
Georgia, Florida, Illinois, Indiana, Kansas, Kentucky, Louisiana, Maine, Maryland, Massachusetts
(invasive non-native), Michigan (invasive non-native), Missouri, New Hampshire (invasive nonnative), New Jersey (invasive non-native), New York (invasive non-native), North Carolina,
Oklahoma, Ohio (invasive non-native), Oregon (invasive non-native), Pennsylvania (invasive nonnative), Rhode Island (invasive non-native), South Carolina, Tennessee, Texas, Vermont, Virginia,
Washington (invasive non-native)), Canada (Ontario(invasive non-native)).
Southern America (native): southern Brazil (Mato Grosso, Rio Grande do Sul, Sao Paulo),
northeast Argentina (Buenos Aires, Cordoba, Corrientes, Entre Rios, Rio Negro, Santa Fe), Paraguay
(Central, Paraguari), Uruguay.
Notes: The plant is present in New Zealand and has been traded for over 30 years, but has not
naturalized. There is just one known outside pond site, which is not a tropical site (Karangahape
Gorge), where the plant grows in cool spring-fed water; this is not a tropical site (P Champion, pers.
comm.). Champion and Clayton (2001) state in the report on Border Control for Potential Aquatic
Weeds in New Zealand that climate modelling suggests that this species could potentially grow in
most lowland New Zealand water bodies; however, it does not reproduce sexually outside of its
native range and limited competitive studies have shown that it would be displaced by Egeria densa.
Champion experimentally investigated potential weediness of some weeds under New Zealand
conditions by growing them in competition with known weeds and New Zealand natives.
Experiments were run over 18 months, assessing plant performance (cover and height) throughout
this time and measuring the biomass of each species at the end of this time. The results showed that
C. caroliniana had no significant impact on either native or other introduced plants under
experimental conditions (Champion et al., 2004). The species is categorized as a "to evaluate further"
species in New Zealand. The plant has been recorded as thriving in alkaline waters. Champion
wondered about the sensitivity of the plant to water chemistry as a condition to its establishment.
In Canada, Wilson et al. state in 2002 that “the plant is recorded in Kasshabog Lake in the Kawartha
Lakes of southern Ontario. It is otherwise absent from natural ecosystems in Canada, Ontario. It can
clearly survive in south-central Ontario, as the populations observed in Kasshabog Lake have
overwintered and continued to grow and spread since the plant was first identified there in 1992. This
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appears to be the most northern site colonized by C. caroliniana to date in North America, and
possibly in the world (exact localisation in Japan is unknown)”.
“Since then, no eradication or control measures have been applied and C. caroliniana has continued
to spread in the one watershed where it is known in Canada. It has been reported from several bays in
Kasshabog Lake (occupying approximately 16% of the lake's surface area), and has also spread south
out of Kasshabog Lake, down the North River into South Lake (about 8 km) and south out of South
Lake and into Big Bass Bay (about 3 km). It spreads by fragments that are carried on the currents
down the river. It grows in very dense monocultures where it occurs, and has been shown to replace
native species. So far, it has not been reported anywhere else in Ontario (or Canada) outside this
watershed” (C Wilson, personal communication, 2006).
In Australia, C. caroliniana is primarily found in rivers and dams of coastal Queensland and New
South Wales. However, isolated populations occur from Darwin to Melbourne (Mackey and
Swarbrick, 1997).
In England, the species has been present in the South-East since 1969 (definition: Kent, Sussex,
Surrey, Hampshire, Isle of Wight, Berkshire, Oxfordshire, Buckinghamshire). It is considered an
“established taxa reproducing vegetatively or sexually and thus present as self-sustaining” (Hill et
al., 2005). C. caroliniana was found in the Forth and Clyde Canal in 1969 and has been introduced
from discarded aquarium material, but is no longer present. In 1991 it was found in the Basingstoke
Canal, and was still present there in 1995. It may be overlooked elsewhere (Preston et al., 2002).
In Belgium, the plant has been naturalized in a pond containing indigenous species such as
Potamogeton spp., Myriophyllum spp. It is present on a part of the pond, but has not shown invasive
behaviour and did not reach the other ponds (F Verloove, pers. comm., 2006).
In Hungary, C. caroliniana is a neophyte which is considered naturalized in warmer waters because
it overwinters in there, and is casual in colder waters (I Dancza, pers. comm., 2006).
In the Netherlands, the plant is present in three locations (T Rooteveel, pers. com., 2007):
- in Maastricht, near Roermond (south of the Netherlands): it was first found in 1988 as an
aquarium escapee in the river Meuse, and is still present in mixed vegetation and in rather
low number. Although fragments have been seen floating away, no other infestation nearby
have been found and the plant had not spread. Water there is euthrophic and rather turbid
with low visibility (less than 1 m). Water levels are variable. No specific action was taken to
manage the plant.
- Recently, the plant was also found near Loosdrecht in the west of the Netherlands. The
invasion started in the late 1990s on a recreational site and was presumably due to dumping
of aquarium material in the canal. In 2005, total obstruction of the canal and its direct
surroundings was noted, and the plant colonized a considerable area and smothered native
vegetation. The infestation reached approximately 1 km from the initial site and various
water-types had been invaded. Boating, fishing and swimming became impossible. Until now
the infestation is in an area where the bottom of the canals mainly consists of sands, with
some organic matter on top, and the water is euthrophic. C. caroliniana also grows in areas
where waters have suffered euthrophy. Over the past 15 years, measures have been
undertaken to lower the nutrient load, which resulted in the return of submerged aquatic
macrophytes. The Dutch Board decided to eliminate the plant and started an eradication
programme in 2006, which was pursued in 2007. Plants were uprooted with a laser jet and
collected for destruction. Small starting infestations were taken out by hand. Cost of the
operation was EUR 350,000. The Dutch Board estimates that the infestation has been reduced
by 75%.
- In summer 2007, the plant was reported in Oranjekannal, in a canal on the Drenthe which has
drainage (in dry summers) and irrigation functions. Canals in this region have been
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recovering from severe euthrophy caused by the potato starch industry. C. caroliniana grows
in between a dense vegetation of Myriophyllum heterophyllum, another exotic species which
covers several kilometres of canal. Patches of C. caroliniana have shown to out-compete M.
heterophyllum. The local Water Board took action on M. heterophyllum and cut a strip of
vegetation in the middle of the canal to improve drainage. This measure was quite successful
on M. heterophyllum, but C. caroliniana re-colonized the open space very efficiently.
The plant was recorded in Greece, but this occurrence could not be confirmed (Schooler, pers. com.
2007).
History of introduction and spread
C. caroliniana is native to South America and some southern areas of North America. It is not clear
to what extent this species is native to northern areas of the U.S., though it is found in a number of
northern states. Reportedly, it is an aggressive species in northern and southern areas of the U.S. It
has been dispersed throughout the world by the aquarium trade (Australian Department of the
Environment and Heritage, 2003).
Pathways of movement
Natural spread
The plant spreads primarily by stem fragments or rhizomes dispersed by water.
Plant fragments can be accidentally dispersed by human activities by attaching to fish gear or to the
hull, anchor line, engine, other part of a boat, across drainages and perhaps by waterfowl (Australian
Department of the Environment and Heritage, 2003; Schooler et al., 2005).
Seeds are thought to be dispersed mainly by birds, by sticking to their feathers or to mud on their
feet. They can also be dispersed by water current (Ørgaard, 1991; Sanders, 1979).
Movement in trade
It has been widely used in the aquarium trade for many years, which has probably been the source of
some local infestations as well as infestations in places as far away as Australia (University of Maine
Cooperative Extension). The most common method of introduction is the dumping of old aquarium
plants. The spread of the plant has also been aided in Australia by deliberate “seeding” of waterways
to ensure a supply for the aquarium trade (Australian Department of the Environment and Heritage,
2003). Large numbers of plants are sent from Florida to the rest of the U.S. for commercial use. It is
also grown commercially in Asia for export to Europe and other parts of the world. Small-scale, local
cultivation occurs in some areas (Ørgaard, 1991).
According to the French NPPO (Paris Border Inspection points) in Roissy, statistics show that in
2005, 78.860 thousands plants of Cabomba spp. where imported from Indonesia and Singapour
(EPPO Reporting Service 2007/016). In 2003, 254.850 thousands of Cabomba spp. where imported
from Indonesia, Singapour and Hungary, of which 10.000 thousands being C. caroliniana imported
from Hungary. Moreover, there are at least two producers of aquatic plants in Europe: one in
Germany (Denerle), and one in Denmark (Tropica).
Impact
Effects on plants
In Australia, the trade represents a $300,000 a year industry, while conservative 1999 estimates place
the national cost of C. caroliniana control at more than $500,000. According to Wilson et al. (2001),
wild rice production (Zizania palustris L.) in Canada could also be potentially affected by C.
caroliniana.
Moreover, plant extracts are allelopathic inhibiting the germination of wheat and lettuce seed and
vegetative growth in some aquatic species (Randall, 1997).
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Environmental and social impact
C. caroliniana is a highly competitive, densely growing and persistent plant. Upon introduction into
a new water body it progressively colonizes near shore areas, where it intercepts sunlight to the
exclusion of other submerged plants, crowds out native plants, clogs waterways, disrupting natural
flow and hindering recreational activities such as fishing and boating. In Australia, the weed can
smother native submerged plants such as pondweeds (Potamogeton spp.), stoneworts (Chara spp.),
hornwort (Ceratophyllum demersum), and water nymph (Najas tenuifolia) (Mackey and Swarbrick,
1997). It may also reduce germination of desirable native emergent plants. It is likely that
infestations of C. caroliniana affect light level in the water column, shading out other submerged
plants (Wilson, 2001). In relatively shallow lakes and ponds, fanwort can colonize the entire water
body. When dense mats of C. caroliniana decay, the available oxygen in the water may be depleted
and cause foul-smelling water. The resulting low oxygen conditions can lead to fish kills and harm
other aquatic organisms (Commonwealth of Massachusetts). In Northern Queensland, populations of
native animals such as platypus and water rat are smaller in infested creeks (Australian Department
of the Environment and Heritage, 2003).
It can impede swimming and boating. In addition, it is a potential danger to swimmers who may
become entangled in the long stems (Schooler et al., 2005). Mackey and Swarbrick (1997) report the
forced closure of fishing camps in the USA, resulting in significant losses of income.
Dense infestations can degrade aesthetic and scenic qualities of sites, directly influencing tourism
and real estate values (University of Maine Cooperative Extension). In cases of severe infestation, it
can raise water level to the point of overflow and cause heavy seepages (Preconic Estuary Program).
It can also significantly reduce water storage capacity and taint drinking water supplies. Water
treatment costs can be increased by up to $50 a megalitre (Australian Department of the Environment
and Heritage, 2003).
Summary of invasiveness
This plant is considered an aquatic weed. It has been dispersed worldwide as an aquarium plant and
has proven to be invasive almost in every place where it has been introduced. It can spread naturally
very efficiently by vegetative reproduction by rhizomes or stem fragments. It can grow in a wide
range of habitats, conditions and climatic conditions. It is still traded as an aquarium plant.
Control
Preventing the dumping of aquaria waters into natural habitats is a preliminary and very important
control action. People need to be educated to buy alternative species of aquarium plants to stop the
demand for C. caroliniana (Australian Department of the Environment and Heritage, 2003).
Moreover, the plant can be unintentionally spread attached to fish gear or to the hull, anchor line,
engine, or other part of a boat. Boaters should clean their boats before moving between water bodies
(Preconic Estuary Program) and fishermen should clean their equipment.
C. caroliniana’s weakness is that it requires direct sunlight for growth. Thus, shading by reestablishment of shoreline vegetation or artificial means is a possible method of control. This
method is best suited to small, early infestations.
Another method being used is the deliberate lowering of the water level (known as drawdown),
which may be the best option for drinking water supplies. If the base of the water storage dries out
completely there is little chance of C. caroliniana surviving, but if it remains damp, there is more
than 50% chance it will return (Australian Department of the Environment and Heritage, 2003). The
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drawdown will be effective if done to an adequate depth and for enough time to prevent re-growth
from seeds. However this control technique will certainly destroy fish, aquatic organism populations
and possibly also reptiles, amphibians, and may alter downstream conditions (Commonwealth of
Massachusetts). Extreme drying is required to prevent regrowth from seed; the plant easily fragments
from disturbance, therefore control activity could contribute to the spread of the plant is great care is
not taken.
Cultural and mechanical control
C. caroliniana is extremely difficult to remove once it becomes established. While hand pulling may
be sufficient for small, isolated populations, it is not a viable long-term control method. Physical
cutting and removal of plant matter is a suitable method for closed water bodies with heavy
infestations. Unfortunately, this method is time-consuming, expensive, and not necessarily effective,
because plant material is likely to fragment and create new elements of dispersal (Preconic Estuary
Program). Morevover, C. caroliniana grows so quickly that treatment by this method is only likely to
maintain a clear water surface for a few weeks. Trials of mechanical removal in Lake Macdonald
(Queensland, Australia) showed that 2 treatments over a month resulted in clearer water and some
regrowth of other desirable aquatic species. The cost of mechanical removal of this plant from dams
is very high: at Marlow lagoon (Northern Territory, Australia) more than $400,000 was spent
initially trying to control the weed without eradicating it. Moreover, operators and their equipment
require rigorous hygiene protocols to minimise spread. Using a venture dredge, which is like a giant
vacuum cleaner, can help in minimizing fragmentation and to extract the root ball (Australian
Department of the Environment and Heritage, 2003). Disposal of the plants can be done by drying
and burning the entire plants.
Hand pulling by divers is more suited to isolated plants and small areas. A 100 m strip was hand
pulled in Lake Macdonald (Queensland, Australia) but within 2 weeks it was difficult to find any
trace of the cleared area (Australian Department of the Environment and Heritage, 2003).
In the Netherlands the local Water Authority has attempted an eradication programme for the first
small focus of Cabomba found in the country in 2006 (T Rotteveel, pers. comm., 2006).
Chemical control
Herbicides have to be used carefully in aquatic ecosystems as these chemical products could affect
non-target species and are mostly undesirable for use in vulnerable aquatic ecosystems. In some
cases herbicides have been used successfully; in Marloon Lagoon (Northern Territory, Australia), a
$4000 herbicide programme successfully cleared the infestation after unsuccessful attempts at
eradication by mechanical control (Australian Department of the Environment and Heritage, 2003).
No herbicide registered for C. caroliniana control in bodies of drinking water.
In North America, the contact herbicide Endothal has given excellent control, and the systemic
herbicide Fluridone has given good control (Commonwealth of Massachusetts).
In Australia, experience has shown that a slow action herbicide is needed to help prevent oxygen
depletion of the water resulting from massive decomposition of huge volumes of dead vegetation
(Agriculture & resource Management Council of Australia & New Zealand).
Biological control
Biological control has not been attempted. However, currently a project funded under the Natural
Heritage Trust in Australia is looking for potential biological control agents in the native range of the
weed (Australian Department of the Environment and Heritage, 2003; Cabrera Walsh & Julien,
2005).
Regulatory status
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C. caroliniana is listed on the “State Noxious Weed Lists for 45 States” of North America.
It is also listed with different invasive statuses in California, Connecticut, Maine, Massachusetts,
Vermont and Washington. It is nevertheless considered extinct in Indiana and threatened in
Kentucky (USDA Plants profile).
In Australia, C. caroliniana is a weed of national significance. It is listed in all the Australian States
with various statuses and is still illegally sold as an aquarium plant in many States (Australian
Department of the Environment and Heritage, 2003).
The species is traded extensively by the aquarium trade and it is considered imperative that strict
quarantine regulations be enforced in the ASEAN region because of its potential to cause serious
problems in their aquatic ecosystems (Mackey & Swarbrick, 1997).
The species has been included in the recent review of Scottish legislation (completed in June 2005).
Schedule 9 of the Countryside and Wildlife Act 1981 lists plants that cannot be planted or caused to
grow in the wild (R Baker, pers. comm.).
Acknowledgments
The following people provided information for this data sheet:
R Baker (UK), r.baker@csl.gov.uk; P Champion (NZ), p.champion@niwa.co.nz; I Dancza (HU),
Dancza.Istvan@ntksz.ontsz.hu; M Julien (AU), mic.julien@csiro-europe.org; R Randall (AU),
RPRandall@agric.wa.gov.au; A J W Rotteveel (NL), a.j.w.rotteveel@minlnv.nl; C Wilson (CA)
wilsonce@inspection.gc.ca.,
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References (Internet links where consulted in August 2006)
Agriculture & resource Management Council of Australia & New Zealand, Australian & New
Zealand Environment & Conservation Council and Forestry Ministers (2000) Weeds of National
Significance Cabomba (Cabomba caroliniana) Strategic Plan. National Weeds Strategy Executive
Committee, Launceston.
Australian Department of the Environment and Heritage (2003) Cabomba (Cabomba caroliniana).
Weeds of National Significance: Weed Management Guide Department of the Environment and
Heritage and the CRC for Australian Weed Management, 2003.
http://www.deh.gov.au/biodiversity/invasive/publications/c-caroliniana.html
Britton NL, Brown A (1913) An illustrated flora of the northern United States, Canada, and the
British possessions, second edition. New York, Scribners. Vol. 2:76.
Cabrera Walsh W, Julien M (2005) Natural enemies of Fanwort (Cabomba caroliniana Gray): First
report on species richness and host ranges, Proceedings of the 45th Annual Meeting of the Aquatic
Plant Management Society, Inc., July 10-13, 2005, Texas (ABSTRACT)
Champion PD, Clayton JS (2000) Border control for potential aquatic weeds. Stage 1. Weed risk
model. Science for Conservation, 141.
http://www.doc.govt.nz/Publications/004~Science-and-Research/Science-forConservation/PDF/sfc141.pdf
Champion PD, Clayton JS (2001) Border control for potential aquatic weeds. Stage 2. Weed risk
assessment. Science for Conservation, 185. 30 p.
http://www.doc.govt.nz/Publications/004~Science-and-Research/Science-forConservation/PDF/SFC185.pdf
Champion PD, Hofstra DE, Clayton JS (2004) Border control for potential aquatic weeds. Stage 3.
Weed risk management. Department of Conservation. National Institute of Water & Atmospheric
Research Ltd.
Information at: http://www.niwascience.co.nz/pubs/wa/12-3/weed
Commonwealth of Massachusetts ~ Department of Conservation and Recreation ~ Office of Water
Resources ~ Lakes and Ponds Program - Fanwort: An Invasive Aquatic Plant. Cabomba caroliniana
http://www.mass.gov/dcr/waterSupply/lakepond/factsheet/fanwort.doc
Denerle (Producer of aquarium plants in Germany) http://www.dennerle.de/
EPPO Reporting Service (2007) Pathway analysis: aquatic plants imported in France (2007/016)
http://archives.eppo.org/EPPOReporting/2007/Rse-0701.pdf
Nomenclatural and Specimen Database of the Missouri Botanical Garden - W3 Tropicos
http://mobot.mobot.org/cgi-bin/search_pick?name=Cabomba+caroliniana
Ørgaard M (1991) The genus Cabomba (Cabombaceae) - a taxonomic study. Nordic Journal of
Botany, 11: 179-203.
Pacific Island Ecosystems at Risk (PIER) Species Info (Undated) Cabomba caroliniana
http://www.hear.org/Pier/species/cabomba_caroliniana.htm
Preconic Estuary Program (Undated) Fanwort, Cabomba caroliniana
9
http://www.peconicestuary.org/InvCabomba.html
Preston CD, Croft JM (1997) Aquatic Plants in Britain and Ireland. Harley Books, Colchester.
Preston CD, Pearman DA, Dines TD (2002) New Atlas of the British and Irish Flora. Oxford: Oxford
University Press.
Randall R (2002) A Global Compendium of Weeds. http://www.hear.org/gcw/alpha_select_gcw.htm
Randall R (1997) Weed potential of Cabomba, Cabomba caroliniana A. Gray (Family:
Cabombaceae). Agriculture Western Australia.
Tropica aquarium plants (Producer of aquarium plants in Denmark)
http://www.tropica.com/default.asp
University of Maine Cooperative Extension, Bulletin n°2522 (Undated) Maine Invasive Plants,
Fanwort, Cabomba –
http://www.umext.maine.edu/onlinepubs/htmpubs/2522.htm
USDA Plants profile – Cabomba caroliniana Gray http://plants.usda.gov/java/profile?symbol=CACA
Washington State's Department of Ecology (2003) Technical Information About Cabomba
Caroliniana (Fanwort). Water Quality Program: Non-Native Freshwater Plants.
http://www.ecy.wa.gov/programs/wq/plants/weeds/aqua006.html
Wilson C, Watler D (2001) Weed Risk Assessment, Fanwort, Cabomba caroliniana Gray. Canadian
Food Inspection Agency. Plant Health Assessment Unit, Science Division, Nepean, Ontario.
December 20, 2001.32 p.
Other sources of information
Cabrera Walsh W, Julien M (2005) Natural enemies of Fanwort (Cabomba caroliniana Gray): First
report on species richness and host ranges, Proceedings of the 45th Annual Meeting of the Aquatic
Plant Management Society, Inc., July 10-13, 2005, Texas (ABSTRACT)
Gibbons MV, Gibbons HL, Sytsma Jr and MD (1994) A Citizen's Manual for Developing Integrated
Aquatic Vegetation Management Plans, 1st Ed. Washington Department of Ecology, Olympia,
Washington
Goldsby TL, Sanders DR (1977) Effects of consecutive water fluctuations on submersed vegetation
of black lake Louisiana USA. Journal of Aquatic Plant Management, 15: 23-28
Gregory PE (1974) Some aspects of the life history and ecology of Cabomba caroliniana Gray. M.S.
Thesis. N.S.U. Natchitoches, Louisiana. 57 pp
Leppakoski et al (ed.). (2002) Invasive Aquatic species of Europe, Kluwer, Dordrecht
Mackey AP (1996) Cabomba spp. in Queensland. Pest Status Review Series - Land Protection
Branch, Department of Natural Resources and Mines, Qld, Australia
Mackey AP, Swarbrick JT (1997) The biology of Australian Weeds, 32. Cabomba caroliniana Gray.
Plant Protection Quarterly 12(4): 154-165.
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Nelson LS, Stewart AB, Getsinger KD (2002) Fluridone effects on fanwort and water marigold.
Journal of Aqatic Plant Management, 40: 58-63
Pieterse AH, Murphy KJ (eds) (1990) Aquatic Weeds - The Ecology and Management of Nuisance
Aquatic Vegetation. Oxford University Press, Oxford. 216 pp.
Reimer DN, Trout JR (1980) Effects of low concentrations of terbutryn on Myriophyllum and
Cabomba. Journal of Aquatic Plant Management, 18:6-9.
Sanders DR Sr (1979) The ecology of Cabomba caroliniana. In: E. O. Gangstad, ed. Weed Control
Methods for Public Health Applications. CRC Press, Boca Raton, FL. pp. 133-146
Schooler SS, Williams DG, Stokes K, Julien M (2005) Invasive Plants: Impacts and Management in
Rivers and Catchments. Riversymposium.
http://www.riversymposium.com/index.php?element=46#search=%22mackey%20swarbrick%22
Tarver DP, Sanders DR Sr (1977) Selected life cycle features of fanwort. Journal of Aquatic Plant
Management, 15: 18-22
Velde G van de, Nagelkerken I, Rajagopal S & bij de Vaate A (2002) Invasions by alien species in
inland freshwater bodies in Western Europe: the Rhine delta. In: Leppakoski et al (ed.). Invasive
Aquatic species of Europe, 360-372. Kluwer, Dordrecht
Wain RP, Haller WT, Martin DF (1983) Genetic relationship among three forms of Cabomba.
Journal of Aquatic Plant Management, 21: pp 96-98
Data on geographical distribution
Argentina, Brazil, Paraguay, Uruguay (Native)
USDA Germplasm Ressources Information Network
http://www.ars-grin.gov/cgi-bin/npgs/html/taxon.pl?400193
Australia (Invasive)
Australia’s virtual herbarium
http://www.rbg.vic.gov.au/cgi-bin/avhpublic/avh.cgi
Smith NM (2002) Weeds of the wet/dry tropics of Australia - A field guide. Environmental Centre
NT, Inc. p. 81.
Australian Department of the Environment and Heritage, (2003) Cabomba (Cabomba caroliniana).
Weeds of National Significance: Weed Management Guide Department of the Environment and
Heritage and the CRC for Australian Weed Management, 2003.
http://www.deh.gov.au/biodiversity/invasive/publications/c-caroliniana.html
Belgium (in Holsbeek)
Denys L, Packet J, Weiss L & Coenen M (2003) Cabomba caroliniana (Cabombaceae) houdt stand
in Holsbeek (Vlaams-Brabant, België). Dumortiera 80: 35-40.
Canada
Wilson C, Watler D (2001) Weed Risk Assessment, Fanwort, Cabomba caroliniana Gray. Canadian
Food Inspection Agency. Plant Health Assessment Unit, Science Division, Nepean, Ontario.
December 20, 2001.32 p.
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China (Eastern) (Invasive)
Zhang X, Yang Z, Jiakuan C (2003) Fanwort in Eastern China: An Invasive Aquatic Plant and
Potential Ecological Consequences. AMBIO: A Journal of the Human Environment, 32:158-159.
Greece (unconfirmed)
Schooler SS, Williams DG, Stokes K, Julien M (2005) Invasive Plants: Impacts and Management in
Rivers and Catchments. Riversymposium.
http://www.riversymposium.com/index.php?element=46#search=%22mackey%20swarbrick%22
Cook CDK (1985) Range extensions of aquatic vascular plant species. Journal of Aquatic Plant
Management 23: 1–7. (Recorded by Champion et al., 2001 that the plant is present in southern
Europe).
Hungary
Steták D (2004) An aquarium plant in natural waters and canals of Hungary: the fanwort (Cabomba
caroliniana). Kitaibelia, 6 (1) pp 165-171 (abstract)
India, Japan, Malaysia, New Guinea
Washington State's Department of Ecology (2003) Technical Information About Cabomba
Caroliniana (Fanwort). Water Quality Program: Non-Native Freshwater Plants.
http://www.ecy.wa.gov/programs/wq/plants/weeds/aqua006.html (Updated in 2003)
Japan
Greenery Technology and Landscape Planning (2007) Invasive Plants Database
http://invasive.m-fuukei.jp/
New Caledonia (Invasive)
MacKee H S (1994) Catalogue des plantes introduites et cultivées en Nouvelle-Calédonie. Muséum
National d'Histoire Naturelle, Paris, 164 p.
http://www.hear.org/pier/species/cabomba_caroliniana.htm
United Kingdom (the)
Hill M, Baker R, Broad G, Chandler P J, Copp G H, Ellis J, Jones D, Hoyland C, Laing I, Longshaw
M, Moore N, Parrott D, Pearman D, Preston C, Smith R M, Waters R (2005) Audit of non-native
species in England. English Nature Research Reports n° 662. 81 p.
http://www.english-nature.org.uk/pubs/publication/pdf/662.pdf
Preston CD, Croft JM (1997) Aquatic Plants in Britain and Ireland. Harley Books, Colchester.
Preston C D, Pearman D A, Dines T D (2002) New Atlas of the British and Irish Flora. Oxford:
Oxford University Press.
Stace C (1997) New flora of the British Isles. 2nd Edition. Cambridge University Press, Cambridge,
U.K.
BSBI Atlas Update Project - Hectad distribution map of Cabomba caroliniana (Carolina Water
Shield) in Britain and Ireland
http://www.bsbiatlas.org.uk/map_page.php?spid=5463&sppname=Cabomba%20caroliniana&comm
name=Carolina%20Water%20Shield
Netherlands (the),
Ing. Ton Rotteveel, Dutch Plant Protection Service, personal communication, 2006.
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USA
USDA Plants profile – Cabomba caroliniana Gray http://plants.usda.gov/java/profile?symbol=CACA
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