Carrotwood, Cupaniopsis anacardioides, is an evergreen tree native to
Australia, Indonesia, and New Guinea. It is a slender tree usually with a
single trunk that has dark gray outer bark covering inner bark that is often
orange in color. It is this unusual feature that gives C. anacardioides
its common name. The compound leaves are comprised of 4-12 leathery,
shiny, yellowish green leaflets with the last two leaflets of each forming a
pair. Leaflets are up to 20 cm long and 7.5 cm wide, with smooth margins and
rounded to slightly indented leaf tips. Small white to greenish yellow flowers
in branched clusters occur at leaf axils. The fruits are defining diagnostic
features, consisting of short-stalked, three-segmented woody capsules up to 0.9
inches across that are yellow-orange when ripen and then dry to brown before
splitting open to reveal three black seeds each covered by a yellow-red crust
(Oliver 1992, Langeland and Burks 1998).
Potentially Misidentified Species
The identifying characteristics noted above, particularly the unusual fruits and the orange inner bark layer, make species determination fairly straightforward.
HABITAT AND DISTRIBUTION
Within it's native range Cupaniopsis anacardioides is found along rocky beaches
and in sand dunes, and in hilly scrub and forested wetlands (Reynolds 1985).
Carrotwood has escaped cultivation to become established in Florida. It is
also grown as an ornamental plant in California but there is no indication of a
similar pest plant situation there.
In Florida, carrotwood can be found in coastal lands and estuarine margins and
riparian zones, and within disturbed wetlands. In coastal counties, carrotwood can be found on both sides
of the state, from Volusia County south on the Atlantic coast and from Pinellas
and Hillsborough counties south on the Gulf coast (Langeland and Burks 1998).
Carrotwood can be found in all six IRL watershed counties and is considered to
be naturalized from at least Brevard County southward. Brevard and Martin
counties were the first on the east coast to contain reproductive populations
(Langeland and Burks 1998, FLEPPC EDD Maps).
LIFE HISTORY AND POPULATION BIOLOGY
Age, Size, Lifespan
This fast growing tree can reach a height of 10 m (Langeland and Burks 1998).
Carrotwood occurs in at least 14 Florida counties and is capable of displacing
native plants to form monotypic stands. Lockhart et al. (1999) report
carrotwood densities are highest in mangrove and coastal hammock habitats,
reaching greater than 24 plants per square meter and 21 plants per square
Carrotwood is monoecious, with both male and female flowers occurring on the
same plant (Lockhart 2006). Sexual reproduction and propagation by means of
seeds is the chief means of reproduction in Cupaniopsis anacardioides, a species
that is recognized as a prolific seed producer (Lockhart et al. 1999). In
Florida, carrotwood flowers from January to March and its fruit ripens in May
and June. Bees are likely to be the main pollinators of carrotwood in Florida,
as they are within the plant's native range (Hawkeswood 1983, ISSG).
When the fruits ripen, they split open to release seeds to the environment.
Seed dispersal by birds and small mammals is important, and transport via water
may be important as well. The germination rate of carrotwood reportedly
remains unknown (Lockhart et al. 1999).
Temperature is likely the key factor limiting the spread of Cupaniopsis anacardioides into north Florida. A temperature of -6°C has been
published as a lethal lower limit for the species, although test specimens
maintained in north Florida have survived winter temperatures as low or lower
than this value (Lockhart 2006).
Carrotwood is tolerant of saline soil conditions as evidenced by its tendency
to invade mangrove marshes and other coastal shoreline habitats.
Carrotwood is tolerant of a wide range of soil moisture conditions and thrives
in disturbed and undisturbed wetlands but can readily adapt to dry areas as
well (Lockhart et al. 1999).
Carrotwood occurs in a variety of natural Florida habitats and often outcompetes and crowds out a variety of native vegetation types.
Cupaniopsis anacardioides was intentionally introduced to south Florida in the
1950s and 1960s as a landscape ornamental plant (Lockhart et al. 1997. 2006).
The freely-seeding plant quickly escaped from cultivation such that established
seedlings were present in a variety of natural and disturbed habitats on both
coasts by 1990 (Menninger 1964, Oliver 1992, Langeland and Burks 1998).
Birds, particularly fish crows (Corvus ossifragus) are the primary
animal dispersal agents of carrotwood seeds which they ingest and can later
deposit a considerable distance from parent plants (Coile 1997, Lockhart et al.
As of 1997, carrotwood was found in 14 coastal Florida counties and reproducing
populations were established in Brevard, Martin, and Sarasota counties and
possibly elsewhere (Lockhart et al. 1997, Langeland and Burks 1998).
Potential to Compete With Natives
Carrotwood is listed as a Category 1 invasive exotic in Florida, capable of
altering native plant communities by displacing native species and changing
community structures or ecological functions (FLEPPC).
Spoil Islands, beach dunes, hammocks, marshes, mangrove and cypress habitats, scrub, coastal prairies and
coastal strand are among the Florida coastal natural habitats susceptible to
invasion by this species (Lockhart et al. 1997, 1999, Gordon 1998).
Once it invades a new area, Cupaniopsis anacardioides can crowd out and
outcompete native vegetation to form dense monospecific stands (Randall and
Possible Economic Consequences of Invasion
Cupaniopsis anacardioides can alter the community structure of native plant
communities, e.g., mangrove marsh, and negative economic as
well as ecological impacts are probable. To minimize impacts, the plant was
added to the DACS Florida Noxious Weed List (5b-57.007 FAC) in 1999. Plants on
the Florida Noxious Weed List, including carrotweed, may not be introduced,
possessed, moved, or released without a permit (Langeland 2006).
Coile N.C. 1997. Risk assessment for carrotwood. Memorandum to Connie Riherd,
Assistant Director, Division of Plant Industry.
Gordon D.R. 1998. Effects of invasive, non-indigenous plant species on
ecosystem processes: Lessons from Florida. Ecological Applications 8:975-989.
Hawkeswood T.J. 1983. Pollination and fruit production of Cupaniopsis
anacardioides (A. Rich.) Radlkf. (Sapindaceae) in Townsville, North
Queensland. 1. Pollination and floral biology. Victorian Naturalist. 100:12-20.
Langeland K.A. 2006. Natural Area Weeds: Carrotwood (Cupaniopsis
anacardioides). UF/IFAS document SS-AGR-165. Avaiable online.
Langeland K.A. and K.C Burks (Eds.). 1998. Identification and Biology of
Non-Native Plants in Florida's Natural Areas. UF/IFAS. 165 p.
Lockhart C.S., Jones A.W., and L. Downey. 1997. The invasion of carrotwood
carrotwood (Cupaniopsis anacardioides) in natural areas. Final Study
Report. Habitat Specialists, Inc. fro FLDEP. 24 p.
Lockhart C.S., Austin D.F., Jones W.E., and L.A. Downey. 1999. Invasion of
carrotwood (Cupaniopsis anacardioides) in Florida natural areas (USA).
Natural Areas Journal 19:254-262.
Lockhart C.S. 2006. Carrotwood (Cupaniopsis anacardioides) data sheet. Plant
Conservation Alliance, Alien Plant Working Group.
Menninger E.A. 1964. Seaside plants of the world. Hearthside Press, Inc., New
York. 303 p.
Oliver J.D. 1992. Carrotwood: A review of the literature. Tech. Report.
Tallahassee: Florida Department of Environmental Protection, Bureau of Aquatic
Plant Management. 10 p.
Randall J.M. and J. Marinelli (eds.). 1996. Invasive plants: Weeds of the
global garden. Brooklyn Botanic Garden Handbook 149. 111 p.