Barbed-wire cactus (Acanthocereus tetragonus)

Present distribution

Scientific name:	Acanthocereus tetragonus (L.) Humm.
Common name(s):	barbed-wire cactus, sword-pear, triangle cactus

This weed is not known to be naturalised in Victoria

Habitat:
Grows on a grassland, alluvial plains (Medina et al 1989), coastal hardwood shrubland (Rutchey et al 2006), coastal Sand Sheet Woodlands
(NatureServe 2002), agricultural areas, rural/disturbed land (ISSG 2008), “dry shores, and upland of mangrove swamps, open sites, second growth in wet to seasonally dry lowlands”… 200m a.s.l. (Gargiullo et al 2008). Sandy soils. Naturalised in Hawaii in dry secondary scrubland (PIER 2006).

Potential distribution

Potential distribution produced from CLIMATE modelling refined by applying suitable landuse and vegetation type overlays with CMA boundaries

Map Overlays Used
Land Use:
No climate match

Broad vegetation types
No climate match

Colours indicate possibility of Acanthocereus tetragonus infesting these areas.

In the non-coloured areas the plant is unlikely to establish as the climate, soil or landuse is not presently suitable.

Red= Very high	Orange = Medium
Yellow = High	Green = Likely

Impact

QUESTION	COMMENTS	RATING	CONFIDENCE
Social
1. Restrict human access?	1-3 m tall… spines 0.5-7 cm long (Gargiullo et al 2008), sometimes 7 m high (PIER 2006), “can form impenetrable thickets” (ISSG 2008) – major impediment – tracks may be closed or impassable	h	m
2. Reduce tourism?	1-3 m tall… spines 0.5-7 cm long (Gargiullo et al 2008) and “can form impenetrable thickets” (ISSG 2008). It occurs in “ agricultural areas, coastland, rural/disturbed, scrub/shrublands” (ISSG 2008) – a cactus would be obvious to most visitors	h	m
3. Injurious to people?	“heavily armed with spines” (Desert Feast 2008)	h	ml
4. Damage to cultural sites?	“Can form impenetrable thickets” (ISSG 2008). It occurs in “ agricultural areas, coastland, rural/disturbed, scrub/shrublands” (ISSG 2008) – moderate visual effect	ml	m
Abiotic
5. Impact flow?	“terrestrial” (Gargiullo et al 2008) – little or negligible affect on water flow	l	mh
6. Impact water quality?	“terrestrial” (Gargiullo et al 2008) – no noticeable affect on dissolved oxygen or light levels	l	mh
7. Increase soil erosion?	“This cactus can form impenetrable thickets threatening native plants” (ISSG 2008) – low probability of large scale soil movement	l	m
8. Reduce biomass?	“This cactus can form impenetrable thickets threatening native plants” (ISSG 2008) and occurs in “agricultural areas, coastland, rural/disturbed, scrub/shrublands” (ISSG 2008), is naturalised in dry secondary scrubland. Can grow to 7m (PIER 2006) – direct replacement of biomass	ml	m
9. Change fire regime?	“This cactus can form impenetrable thickets threatening native plants” (ISSG 2008) and occurs in “agricultural areas, coastland, rural/disturbed, scrub/shrublands” (ISSG 2008), is naturalised in dry secondary scrubland. Can grow to 7m (PIER 2006) – the change in plant matter is likely to cause a moderate change to both frequency and intensity of fire risk	mh	ml
Community Habitat
10. Impact on composition (a) high value EVC	No climate match in Victoria	l	h
(b) medium value EVC	No climate match in Victoria	l	h
(c) low value EVC	No climate match in Victoria	l	h
11. Impact on structure?	“semierect or erect cactus that leans or grows over other plants… forms thickets by the arching 3-to-5 angled stems that root where they touch the ground” (Everitt et al 2002). “This cactus can form impenetrable thickets threatening native plants” (ISSG 2008) – major effect on all layers. Forms monoculture	h	m
12. Effect on threatened flora?	“This cactus can form impenetrable thickets threatening native plants” (ISSG 2008) – therefore it would have the potential to replace vegetation, however the effect on threatened flora is not yet identified	mh	l
Fauna
13. Effect on threatened fauna?	“Can form impenetrable thickets threatening native plants” (ISSG 2008) – has the potential to change habitat dramatically, however to the effect on threatened fauna spp is not yet identified	mh	l
14. Effect on non-threatened fauna?	“This cactus can form impenetrable thickets threatening native plants” (ISSG 2008) – habitat changed dramatically, leading to the possible extinction of non-threatened fauna	h	m
15. Benefits fauna?	Under the general heading of prickly pear, it is said that birds and animals eat the fruit (Jordan 2007). It also flowers at night (Mann 1970), so it may be a food source for nocturnal nectar feeders – may provide some assistance	mh	m
16. Injurious to fauna?	spines 0.5-7 cm long (Gargiullo et al 2008) – large spines or burrs dangerous to fauna	h	mh
Pest Animal
17. Food source to pests?	Under the general heading of prickly pear, it is said that birds and animals eat the fruit (Jordan 2007) – may be a food source to pest birds and insects	ml	m
18. Provides harbour?	“forms thickets by the arching 3-to-5 angled stems that root where they touch the ground” (Everitt et al 2002) – capacity to provide harbour and permanent warrens for foxes and rabbits throughout the year	h	mh
Agriculture
19. Impact yield?	Identified as an “agricultural weed” (Randall 2007) however to what extent is not stated	m	l
20. Impact quality?	Identified as an “agricultural weed” (Randall 2007) however to what extent is not stated	m	l
21. Affect land value?	Identified as an “agricultural weed” (Randall 2007) however to what extent is not stated	m	l
22. Change land use?	Identified as an “agricultural weed” (Randall 2007) however to what extent is not stated	m	l
23. Increase harvest costs?	Identified as an “agricultural weed” (Randall 2007) however to what extent is not stated	m	l
24. Disease host/vector?	The genus Acanthocereus is known to be a host of Pseudococcus jackbeardsleyi (Jack Beardsley mealy bug) which affects leaves and fruits of banana plants (DAFF 2002) – not known to a host for diseases of agriculture in Victoria	l	m

Invasive

QUESTION	COMMENTS	RATING	CONFIDENCE
Establishment
1. Germination requirements?	Although it can grow in shade (Faucon 2005) and has high drought tolerance (Desert Feast 2008) the germination requirements are unknown	m	l
2. Establishment requirements?	Grows in “low deciduous forest” (Ortiz 2001) and can grow in “light shade to shade” (Faucon 2005) – can establish without additional factors	h	m
3. How much disturbance is required?	It occurs in “ agricultural areas, coastland, rural/disturbed, scrub/shrublands” (ISSG 2008) and in Hawaii it is naturalised in dry secondary scrubland (PIER 2006) – establishes in relatively intact ecosystems	mh	m
Growth/Competitive
4. Life form?	Shrub (Ochoterena 2008), vine-like (Desert Feast 2008) – climber	mh	ml
5. Allelopathic properties?	None mentioned in the literature	m	l
6. Tolerates herb pressure?	“The fruit is eaten by several species of birds and mammals including the bob-white quail, white-tailed deer, javelina, and raccoon” (Everitt et al 2002). It is also under a biological control program (AWC 2008): “Not a candidate for eradication: reasonable control is achieved with the mealybug Hypogeococcus festerianus” (AWC 2003) – although biocontrols appear to be effective in Queensland, other animals that eat the fruit aid in spreading it, i.e. capable of flowering/seed production under moderate herbivory pressure	mh	mh
7. Normal growth rate?	“Forms tangled thickets and dominates the shrub stratum” (NatureServe 2002) and can grow “200cm per season” (FNA 2008) – rapid growth rate that will exceed most other species of the same life form	h	m
8. Stress tolerance to frost, drought, w/logg, sal. etc?	“Tolerates brackish water or occasional inundation by seawater… can tolerate moderate amounts of salt wind without injury.” High drought tolerance “does not require and supplemental water once established” (Desert Feast 2008) Hardy to at least -4˚C (Faucon 2005) Acanthocereus needs well drained soil to grow in order to prevent the roots rotting (Dryscapes 2008) – susceptible to waterlogging	mh	ml
Reproduction
9. Reproductive system	“forms thickets by the arching 3-to-5 angled stems that root where they touch the ground” and seed (Everitt et al 2002) – both sexual and vegetative reproduction	h	m
10. Number of propagules produced?	“many seeded” (Everitt et al 2002); numerous small black seeds (Desert Feast 2008) – it is likely to produce over 2000 seeds	h	m
11. Propagule longevity?	Not found in the literature	m	l
12. Reproductive period?	Not found in the literature	m	l
13. Time to reproductive maturity?	Not found in the literature	m	l
Dispersal
14. Number of mechanisms?	“Spread by seed and vegetative reproduction from broken plant parts” (GCCC 2002). Under the general heading of prickly pear, dispersal is said to be by “birds and animals eating the fruit and excreting viable seed” (Jordan 2007)	h	m
15. How far do they disperse?	Under the general heading of prickly pear, dispersal is said to be by “birds and animals eating the fruit and excreting viable seed” (Jordan 2007) – very likely that at least one propagule will disperse greater than one kilometre	h	m

References

Australian Weeds Committee (AWC) (2008) Target species for biological control. Available at http://www.weeds.org.au/management.htm (verified 1 September 2008)

Australian Weeds Committee (AWC) (2003) Appendix A: Short-listing process. Prepared for the Australian Government Bureau of Rural Sciences. Available at
http://affashop.gov.au/PdfFiles/12919_appendices_a_d.pdf (verified 1 September 2008)

Department of Agriculture, Fisheries and Forestry (DAFF) (2002) Importation of Fresh Bananas from the Philippines; Technical information paper. Commonwealth of Australia. Available at http://www.daffa.gov.au/__data/assets/pdf_file/0014/23081/bananatwg.pdf (verified 3 September 2008)

Desert Feast (2008) Sword pear. The Desert Feast: Delicious fruits for arid gardens. Available at http://desert-feast.com/cact_a_d/a_tetrag.html (verified 1 September 2008)

Dryscapes (2008) Jungle Cacti. Available at http://www.dryscapes.eu/10.html (verified 1 September 2008)

Everitt JH, Drawe DL, Lonard RI (2002) Trees, shrubs and cacti of South Texas. Texas Tech University Press, p. 57.

Gargiullo MB, Magnuson B, Kimball L (2008) A field guide to plants of Costa Rica. Oxford University Press, US, p. 211.

Gold Coast City Council (GCCC) (2002) Guidelines for undesirable plants for natural bushland and waterways; Information sheet 5. Landscape strategy – part 3; Bushcare 2. Prepared by the Urban Design, Cultural Heritage and Landscape Unit and Land for Wildlife. Available at http://www.goldcoast.qld.gov.au/attachment%5Cplanningscheme%5Cpolicies%5Cbushcare_2.pdf (verified 1 September 2008)

Invasive Species Specialist Group (ISSG) (2008) Global invasive species database: Acanthocereus tetragonus. Available at http://www.issg.org/database/species/ecology.asp?si=1248&fr=1&sts=&lang=EN (verified 1 September 2008)

Jordan S (2007) Prickly pear. Department of Primary Industries and Fisheries, Queensland. Available at http://www.dpi.qld.gov.au/cps/rde/dpi/hs.xsl/4790_7343_ENA_HTML.htm (verified 3 September 2008)

Mann J (1970) Cacti naturalised in Australia and their control. Department of Lands, Queensland.

Medina E, Cram WJ, Lee HSJ, Luttge U, Popp M, Smith JACm Diaz M (1989) Ecophysiology of xerophytic and halophytic vegetation of a coastal alluvial plain in northern Venezuela. I. Site description and plant communities. New Phytologist 111, 233-243

NatureServe (2002) International classification of ecological communities: Terrestrial vegetation of the united states. Tamaulipan thornscrub ecoregion. NatureServe, Arlington, VA. Available at http://abisw.org/tt/tt_subset.pdf (verified 27 August 2008)

Ochoterena H (2008) The 25th annual meeting of the Willi Hennig society. Cladistics 24, 82-107

Ortiz, JRR (2001) Information sheet on Ramsar wetlands. Available at http://www.wetlands.org/reports/ris/4MX001en.pdf (verified 1 September 2008)

PIER (2006) Acanthocereus tetragonus. Pacific Island Ecosystems at Risk. Available at http://www.hear.org/pier/species/Acanthocereus_tetragonus.htm (verified 27 August 2008)

Randall R (2007) Acanthocereus tetragonus (Cactaceae). Global Compendium of Weeds. Available at http://www.hear.org/gcw/species/acanthocereus_tetragonus/ (verified 3 September 2008)

Rutchey K, Schal TN, Doren RF, Atkinson A, Ross MS, Jones DT, Madden M, Vilchek KA, Bradley KA, Snyder JR, Burch JN, Pernas T, Witcher B, Pyne M, White, R, Smith TJ III, Sadle J, Smith CS, Patterson ME, Gann GD (2006) Vegetation classification for South Florida natural areas. Open-File Report 2006-1240. United States Geological Survey, Saint Petersburg, Florida. Available at http://sflwww.er.usgs.gov/publications/ofr/2006-1240/OFR_2006_1240.pdf (verified 27 August 2008)

Global present distribution data references

Australian National Herbarium (ANH) (2008) Australia’s Virtual Herbarium, Australian National Herbarium, Centre for Plant Diversity and Research, Available at http://www.anbg.gov.au/avh/ (verified 3 September 2008).

Global Biodiversity Information Facility (GBIF) (2008) Global biodiversity information facility, Available at http://www.gbif.org/ (verified 3 September 2008).

Feedback

Do you have additional information about this plant that will improve the quality of the assessment?
If so, we would value your contribution. Click on the link to go to the feedback form.

Page top