Brazilian oxalis (Oxalis brasiliensis)

Present distribution

Scientific name:	Oxalis brasiliensis Larrañaga
Common name(s):	Brazilian oxalis

This weed is not known to be naturalised in Victoria

Habitat:

Herb growing to 15cm long (Conn 1992) with creeping stems (Richardson et al 2006). Garden escape (Conn 1992). Grows along roads, near creeks and rivers (Harden 2002). O.brasiliensis is cold sensitive (NZPCN) and requires full sun to flourish (Dave’s Garden). Grows vigorously during winter (Shiriashi 2005). O. brasiliensis is cold sensitive (NZPCN), frost intolerant (Bryan 2002). O. brasiliensis can tolerate drought. O. brasiliensis does not cope with over watering (Dave’s Garden) - indicates intolerance to water logging. O. brasiliensis requires full sun to flourish (Dave’s Garden).

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:
horticulture perennial; horticulture seasonal; pasture dryland; pasture irrigation

Ecological Vegetation Divisions
Coastal; heathland; grassy/heathy dry forest; lowland forest; foothills forest; forby forest; damp forest; riparian; wet forest; western plains woodland; basalt grassland; alluvial plains grassland; semi-arid woodland; alluvial plains woodland; riverine woodland/forest; chenopod shrubland; chenopod mallee; hummockgrass mallee; lowan mallee;

Colours indicate possibility of Oxalis brasiliensis infesting these areas.

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

map showing the potential distribution of braxilian oxalis

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

Impact

QUESTION	COMMENTS	RATING	CONFIDENCE
Social
1. Restrict human access?	Herb growing to 15cm long (Conn 1992) with creeping stems (Richardson et al 2006). Grows near creeks and rivers (Harden 2002) Size of oxalis brasiliensis would not restrict access in any way. - Minimal or negligible impact	L	H
2. Reduce tourism?	Herb growing to 15cm long (Conn 1992) with creeping stems (Richardson et al 2006). Inflorescences pale mauve, pink to purple (Conn 1992). - O. brasiliensis is a small herb which wouldn’t be obvious to the average visitor.	L	MH
3. Injurious to people?	No evidence of toxic properties. - No effect, no prickles, no injuries	L	L
4. Damage to cultural sites?	Herb growing to 15cm with creeping stems (Richardson et al 2006). Flowers range from pale mauve, pink to purple (Conn 1992). O. brasiliensis grows near creeks and rivers (Harden 2002). Flowers may be noticeable but would have little or negligible effect on aesthetics or structure of site. - Moderate visual effect	ML	MH
Abiotic
5. Impact flow?	Herb growing to 15cm long (Conn 1992). A terrestrial weed growing near creeks and rivers (Harden 2002) - Little or negligible affect on water flow.	L	M
6. Impact water quality?	Herb growing to 15cm long (Conn 1992). A terrestrial weed growing near creeks and rivers (Harden 2002) - Noticeable but minor effects in dissolved o2 or light levels.	M	MH
7. Increase soil erosion?	No information	MH	L
8. Reduce biomass?	No information	MH	L
9. Change fire regime?	Frequency of O. brasiliensis increased after fire (Overbreck 2005). No evidence that O. brasiliensis alters the normal fire regime.	MH	L
Community Habitat
10. Impact on composition (a) high value EVC	EVC = Damp Forest (E); CMA = West Gippsland; Bioregion = Strzelecki Ranges; VH CLIMATE potential. Herb growing to 15cm long (Conn 1992) with creeping stems (Richardson et al 2006). Grows near creeks and rivers (Harden 2002) - Very little displacement of any indigenous species. Sparse scattered infestations.	L	MH
(b) medium value EVC	EVC = Heathy Herb-rich Woodland (D); CMA = Glenelg Hopkins; Bioregion = Glenelg Plain; VH CLIMATE potential. Herb growing to 15cm long (Conn 1992) with creeping stems (Richardson et al 2006). Grows near creeks and rivers (Harden 2002) - Very little displacement of any indigenous species. Sparse scattered infestations.	L	MH
(c) low value EVC	EVC = Riparian Forest (LC); CMA = Goulburn Broken; Bioregion = Highlands – Northern Fall; VH CLIMATE potential. Herb growing to 15cm long (Conn 1992) with creeping stems (Richardson et al 2006). Grows near creeks and rivers (Harden 2002) - Very little displacement of any indigenous species. Sparse scattered infestations.	L	MH
11. Impact on structure?	Herb growing to 15cm long (Conn 1992) with creeping stems (Richardson et al 2006). A terrestrial weed growing near creeks and rivers (Harden 2002) - Minor or negligible effect on 20% of the floral strata/layers present; usually effecting only one of the strata	L	MH
12. Effect on threatened flora?	Herb growing to 15cm long (Conn 1992) with creeping stems (Richardson et al 2006). - No threatened flora affected due to fauna not co-existing within infested area or strata	L	M
Fauna
13. Effect on threatened fauna?	Herb growing to 15cm long (Conn 1992). - No threatened fauna affected due to fauna not coexisting within infested area or strata	L	MH
14. Effect on non-threatened fauna?	Herb growing to 15cm long (Conn 1992). - No fauna affected due to fauna not coexisting within infested area or strata	L	MH
15. Benefits fauna?	Herb growing to 15cm long (Conn 1992). Fruit of O. brasiliensis is not known in Australia (Harden 2002). - Provides very little support to desirable species	H	MH
16. Injurious to fauna?	No evidence of toxic properties. - No effect.	L	L
Pest Animal
17. Food source to pests?	Fruit of O. brasiliensis is not known in Australia (Harden 2002). Herb growing to 15cm with creeping stems (Richardson et al 2006). Small herb with fruit absent in Australia is not likely to be a food source. - Provides minimal food for pest animals.	L	MH
18. Provides harbor?	Herb growing to 15cm with creeping stems (Richardson et al 2006). - Small herb is unlikely to provide harbour for pest species.	L	MH
Agriculture
19. Impact yield?	Herb growing to 15cm long (Conn 1992) with creeping stems (Richardson et al 2006). Long lived perennial herb(NZPCN). O. brasiliensis inhibited radicle elongation in lettuce and some weed seedlings by its root exudates. It can also suppress above ground biomass (Shiriashi et al.) - Minor quality on quantity of yield	ML	MH
20. Impact quality?	Herb growing to 15cm long (Conn 1992) with creeping stems (Richardson et al 2006). Long lived perennial herb(NZPCN). O. brasiliensis inhibited radicle elongation in lettuce and some weed seedlings by its root exudates. It can also suppress above ground biomass (Shiriashi et al.) - Minor impacts on the quality of yield	Ml	MH
21. Affect land value?	Herb growing to 15cm long (Conn 1992) with creeping stems (Richardson et al 2006). Long lived perennial herb(NZPCN) Small herb will have minimal impact on the value of the land. - Little or None	L	MH
22. Change land use?	Herb growing to 15cm long (Conn 1992) with creeping stems (Richardson et al 2006). Long lived perennial herb(NZPCN) Small herb unlikely to greatly affect the land use in order to cause a change. - Little or no change	L	MH
23. Increase harvest costs?	Herb growing to 15cm long (Conn 1992) with creeping stems (Richardson et al 2006). Long lived perennial herb(NZPCN) Small herb is unlikely to create any major harvesting costs - Little or none	L	MH
24. Disease host/vector?	No evidence to suggest this species is a host/vector for disease.	MH	L

Invasive

QUESTION	COMMENTS	RATING	CONFIDENCE
Establishment
1. Germination requirements?	O. brasiliensis is cold sensitive (New Zealand Plant Conservation Network [NZPCN]) and requires full sun to flourish (Dave’s Garden). O. brasiliensis grows vigorously during winter and early spring (Shiriashi 2005) - Requires natural seasonal disturbances such as seasonal rainfall, spring/summer temperatures for germination	MH	MH
2. Establishment requirements?	O. brasiliensis requires full sun to flourish (Dave’s Garden). O. brasiliensis is a garden escape (Conn 1992) growing along roads, near creeks and rivers (Harden 2002). -Requires more specific requirements to establish (eg. Open space or bare ground, access to direct light and rainfall)	ML	MH
3. How much disturbance is required?	Garden escape (Conn 1992). Grows along roads, near creeks and rivers (Harden 2002). - Establishes in highly disturbed natural ecosystems (roadsides, wildlife corridors, tourist areas or campsites) or in overgrazed pastures/poorly growing or patchy crops	ML	MH
Growth/Competitive
4. Life form?	Long lived perennial herb(NZPCN) Other	L	M
5. Allelopathic properties?	O. brasiliensis inhibited radicle elongation in lettuce and some weed seedlings by its root exudates. It can also suppress above ground biomass (Shiriashi et al.2005) - Allelopathic properties seriously effecting some plants	MH	MH
6. Tolerates herb pressure?	No information found	M	L
7. Normal growth rate?	O. brasiliensis grows vigorously during winter and early spring (Shiriashi et al 2005) -Growth rate equal to the same life form	M	MH
8. Stress tolerance to frost, drought, w/logg, sal. etc?	O. brasiliensis is cold sensitive (NZPCN), frost intolerant (Bryan 2002). O. brasiliensis can tolerate drought. O. brasiliensis does not cope with over watering (Dave’s Garden)- indicates intolerance to water logging. -May be tolerant of one stress, susceptible of at least two	L	M
Reproduction
9. Reproductive system	Seed apparently not formed in Australia and New Zealand (Harden 2002; NZPCN) Spreads from bulbils formed along creeping stems. (Richardson et al. 2006) Although seeds are present in countries where O. brasiliensis is native (South America), in Australia there is no evidence of seeds being produced. - Reproduction is both vegetative and sexual reproduction	H	MH
10. Number of propagules produced?	Unknown	MH	L
11. Propagule longevity?	Unknown	MH	L
12. Reproductive period?	Long lived perennial herb (NZPCN) Perennial habit means O. brasiliensis will live for more than 3 years, and will reproduce annually, via sexual and vegetative methods. - Mature plants produce viable propagules for 3-10 years.	MH	M
13. Time to reproductive maturity?	Offshoots of oxalis species will flower within one years growth (Bryan 2002) - O. brasiliensis reaches maturity and produces viable propagules, and vegetative propagules become separate individuals between 1-2 years.	MH	MH
Dispersal
14. Number of mechanisms?	O. brasiliensis is dispersed in garden waste and rubbish, and by vegetative extension (NZPCN). In Australia the main dispersal mechanism is vegetative growth and human dispersal. - Deliberate (or accidental) human dispersal	ML	M
15. How far do they disperse?	O. brasiliensis is dispersed in garden waste and rubbish, and by vegetative extension (NZPCN). In Australia the main dispersal mechanism is vegetative growth and accidental human dispersal. Due to accidental human dispersal, and transport via rubbish or garden waste increases the potential dispersal distance. - Very likely that at least one propagule will disperse greater than one kilometre	H	M

References

Bryan JE. (2002) ‘Bulbs.’ (Timber Press: Oregon)

Conn J. (1992) for PlantNet, New South Wales Flora Online, available at http://plantnet.rbgsyd.nsw.gov.au/cgi-bin/NSWfl.pl?page=nswfl&lvl=sp&name=Oxalis~brasiliensis

Harden GJ. (1992) Flora of New South Wales. Volume 3. Royal Botanic Gardens Sydney, UNSW Press.

New Zealand Plant Conservation Network, available at http://www.nzpcn.org.nz/exotic_plant_life_and_weeds/detail.asp?WeedID=2037 (verified 28 November 2008)

Overbreck G (2005) Effect of fire on vegetation dynamics in plant types in subtropical grassland in Brazil.

Oxalis brasiliensis in Dave’s Garden, available at http://davesgarden.com/guides/pf/print.php?pid=171382 (verified 28 November 2008).

Richardson FJ, Richardson RG and Shepherd RCH. (2006) Weeds of the South-east. An Identification Guide for Australia. Meredith.

Shiriashi S, Watanabe I, Kuno K, Fujii Y. (2005) Evaluation of the allelopathic activity of five oxalidaceae cover plants and the demonstration of potent weed suppression by Oxalis species. Weed Biology and Management 5 128-136

Global present distribution data references

Department of the Environment and Heritage (Commonwealth of Australia). (1993 – On-going) Australian Plant Name Index (APNI) http://www.cpbr.gov.au/apni/index.html (verified 28 November 2008).

United States Department of Agriculture. Agricultural Research Service, National Genetic Resources Program. Germplasm Resources Information Network - (GRIN) [Online Database]. Taxonomy Query. (2009) Available at http://www.ars-grin.gov/cgi-bin/npgs/html/taxgenform.pl (verified 28 November 2008).

Integrated Taxonomic Information System. (2008) Available at http://www.itis.gov/ (verified 28 November 2008).

Global Biodiversity Information Facility (GBIF). (2009) Available at http://www.gbif.org/ (verified 28 November 2008).

Royal Botanic Gardens Melbourne. (2009) Census of Vascular Plants of Victoria. Available at http://www.rbg.vic.gov.au/research_and_conservation/plant_information/viclist (verified 28 November 2008).

Australian National Herbarium (ANH) Australia’s Virtual Herbarium, Centre for Plant Diversity and Research. (2008) Available at http://www.anbg.gov.au/avh/ (verified 28 November 2008).

Missouri Botanical Gardens (MBG). w³TROPICOS, Missouri Botanical Gardens Database. (2007) Available at http://mobot.mobot.org/W3T/Search/vast.html (verified 28 November 2008).

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