Present distribution
| Map showing the present distribution of this weed. | ||||
Habitat: Native - Fynbos ecosystems, South Africa. Exposed granite slopes and on cliffs and rock ledges where there are periods of considerable drought and an absence of soil (Adamson 1927), riparian communities (Vosse 2007). Alt 0-1800 m (AFFD 2008). Invasive in Vic, Tas and SA (Richardson, Richardson, Shepherd 2006), in Heathland and heathy woodland, dry sclerophyll forest and woodland (Carr 1992), sandy and coastal heaths. Good drainage; sandy, acid soils, also grow in well-drained clay soils (Blake, Bell 2002, Heatley 2004). |
Map Overlays Used Land Use: Forestry; horticulture perennial; pasture dryland Ecological Vegetation Divisions Heathland; grassy/heathy dry forest; foothills forest; forby forest; wet forest; high altitude shrubland/woodland; granitic hillslopes; rocky outcrop shrubland; western plains woodland; semi-arid woodland; hummock-grass mallee; lowan mallee; broombush whipstick Colours indicate possibility of Euryops abrotanifolius infesting these areas. In the non-coloured areas the plant is unlikely to establish as the climate, soil or landuse is not presently suitable. |
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QUESTION | COMMENTS | RATING | CONFIDENCE |
Social | |||
1. Restrict human access? | Shrub to 2 m high (AFFD 2008) and grows in riparian zones (Vosse 2007) – may have low nuisance value and impede individual access to waterways | ml | m |
2. Reduce tourism? | Bright yellow flowers (Richardson, Richardson, Shepherd 2006) and can dominate vegetation (Adamson 1935) – minor effects to aesthetics of natural environments | ml | m |
3. Injurious to people? | Injurious qualities are not mentioned in morphological descriptions (Jessop, Toelken 1986, Richardson, Richardson, Shepherd 2006) – no effect, no prickles or injury | l | mh |
4. Damage to cultural sites? | Bright yellow flowers (Richardson, Richardson, Shepherd 2006), can dominate vegetation (Adamson 1935), grows to 2 m high (Windust 2003) and in riparian zones (Vosse 2007) – may have a moderate visual effect to cultural sites in natural areas | ml | m |
Abiotic | |||
5. Impact flow? | can dominate vegetation (Adamson 1935) and grows in riparian zones (Vosse 2007), however does not grow in the water – little or negligible effect on water flow | l | mh |
6. Impact water quality? | Shrub to 2m high (AFFD 2008), can dominate vegetation (Adamson 1935) and grows in riparian zones (Vosse 2007). It also “invades and degrades… watercourses” (GSA nd) – noticeable effects on light levels | ml | m |
7. Increase soil erosion? | Dominate vegetation, however dead bushes were frequent after this dominant phase was over, six and a half years after fire (Adamson 1935) – moderate probability of bare soil, and large scale soil movement | ml | mh |
8. Reduce biomass? | Moderate to high rates of biomass accumulation (Platt et al 2005), dominate after fire (Adamson 1935) and “invades dry forest and coastal heath, smothering understorey plants” (Heatley 2004) (Heatley 2004) – potential to displace larger species and so may slightly decrease biomass | mh | m |
9. Change fire regime? | Dominate vegetation and dead bushes were frequent after dominant phase was over, six and a half years after fire (Adamson 1935) – increasing fuel and so increasing the intensity of fire risk | ml | m |
Community Habitat | |||
10. Impact on composition (a) high value EVC | EVC = Ridged Plains Mallee (E); CMA = Mallee; Bioregion = Lowan Mallee; VH CLIMATE potential | h | h |
(b) medium value EVC | EVC = Sand Heathland (R); CMA = West Gippsland; Bioregion = Wilsons Promontory; VH CLIMATE potential | h | h |
(c) low value EVC | EVC = Heathy Dry Forest (LC); CMA = Goulburn Broken; Bioregion = Central Victorian Uplands; VH CLIMATE potential | h | h |
11. Impact on structure? | Abundant on Cliffs and Rock Ledges on Table Mountain (Adamson 1927), dominant after fire (Adamson 1935), grows in heathland and heathy woodland, dry sclerophyll forest and woodland, and is a serious threat to one or more vegetation formations in Victoria (Carr 1992). “Cases of invasion known or the potential to cause biodiversity losses considered sufficient to require suppression” ranked as able to invade a medium range of habitat types (Platt et al 2005). “Invades dry forest and coastal heath, smothering understorey plants and threatening biodiversity” (Heatley 2004) – major effect on <60% of the floral strata | mh | mh |
12. Effect on threatened flora? | Although this species can dominate (Adamson 1935) and therefore change the vegetation of an area, the effect on threatened flora has not yet been determined. | mh | l |
Fauna | |||
13. Effect on threatened fauna? | Although this species can dominate (Adamson 1935), is a serious threat to one or more vegetation formations in Victoria (Carr 1992) and therefore change the habitats and food availability in an area, the effect on threatened fauna has not yet been determined. | mh | l |
14. Effect on non-threatened fauna? | Dominant after fire (Adamson 1935), is a serious threat to one or more vegetation formations in Victoria (Carr 1992), “Cases of invasion known or the potential to cause biodiversity losses considered sufficient to require suppression” ranked as able to invade a medium range of habitat types (Platt et al 2005). “Invades dry forest and coastal heath, smothering understorey plants and threatening biodiversity” (Heatley 2004) – reduction in habitat for fauna spp., leading to reduction in numbers of individuals | mh | m |
15. Benefits fauna? | Shrub to 2m high (AFFD 2008), can dominate vegetation (Adamson 1935) and grows in riparian zones (Vosse 2007) – may provide alternative harbour to desirable species | ml | m |
16. Injurious to fauna? | Injurious qualities are not mentioned in morphological descriptions (Jessop, Toelken 1986, Richardson, Richardson, Shepherd 2006) – no effect | l | mh |
Pest Animal | |||
17. Food source to pests? | Herbivory of E. abrotanifolius is not covered in the literature – unknown | m | l |
18. Provides harbor? | Shrub to 2m high (AFFD 2008), can dominate vegetation (Adamson 1935) and grows in riparian zones (Vosse 2007). Cover is one of the most important habitat features for both foxes (Saunders et al 1995) and rabbits (Williams et al 1995), indicating that a stand of E. abrotanifolius would provide ideal harbour for rabbits and foxes – capacity to provide harbour and permanent warrens for foxes and rabbits throughout the year | h | m |
Agriculture | |||
19. Impact yield? | “highly aggressive, colonizer of pastures” (GSA nd) and the literature does not mention it as livestock fodder - major impact on quantity of produce | mh | m |
20. Impact quality? | “highly aggressive, colonizer of pastures” (GSA nd) however listed only as an environmental weed, not as an agricultural weed (Blood 2001) – little or negligible impact on quality of yield | l | m |
21. Affect land value? | “highly aggressive, colonizer of pastures” (GSA nd) however listed only as an environmental weed, not as an agricultural weed (Blood 2001) – little or none | l | m |
22. Change land use? | “highly aggressive, colonizer of pastures” (GSA nd) however listed only as an environmental weed, not as an agricultural weed (Blood 2001) – little or no change | l | m |
23. Increase harvest costs? | “highly aggressive, colonizer of pastures” (GSA nd) however listed only as an environmental weed, not as an agricultural weed (Blood 2001) – little or none | l | m |
24. Disease host/vector? | This was not covered in the literature – unknown | m | l |
QUESTION | COMMENTS | RATING | CONFIDENCE |
Establishment | |||
1. Germination requirements? | Germinates prolifically following soil disturbance and fire; germinates early summer and autumn (Heatley 2004) – natural seasonal disturbance | mh | m |
2. Establishment requirements? | “exposed granite slopes on the western side of Table Mountain , South Africa” (Adamson 1927), Grows in riparian, wet, dry and transitional zones (Vosse 2007), grows in Channel areas (TWS 2000), prefers good drainage – sandy, acid soils, also occurs on well-drained clay soils (Heatley 2004), “invades dry forest and coastal heath, smothering understorey plants” (Heatley 2004) – can establish under moderate canopy cover | mh | m |
3. How much disturbance is required? | “occasional garden escapes found along roadsides and in bushland” (Richardson, Richardson, Shepherd 2006), “ability to invade native vegetation with low levels of disturbance” (Platt et al 2005), “spreading in native bush in Tasmania, particularly in sandy heaths” (Blake, Bell 2002) – establishes in healthy and undisturbed ecosystems | h | mh |
Growth/Competitive | |||
4. Life form? | Xerophytic shrub (Adamson 1927) – other | l | h |
5. Allelopathic properties? | Although it was dominant after fire, there were seedlings from other species pushing through (Adamson 1935) – indicate no allelopathic properties | l | h |
6. Tolerates herb pressure? | Herbivory of E. abrotanifolius is not covered in the literature – unknown | m | l |
7. Normal growth rate? | Dominate after fire (Adamson 1935) and smothers understorey (Heatley 2004) – rapid growth rate that will exceed most other species of the same life form | h | mh |
8. Stress tolerance to frost, drought, w/logg, sal. etc? | Becomes dominant after fire (Adamson 1927) – tolerant to fire Abundant on Cliffs and Rock Ledges on Table Mountain, where there are periods of considerable drought (Adamson 1927) – tolerant to drought Good drainage – prefers sandy, acid soils, also occurs on well-drained clay soils (Heatley 2004) – intolerant to waterlogging Frost-tender (Windust 2003) – intolerant to frost Tolerance to salinity – unknown. | mh | m |
Reproduction | |||
9. Reproductive system | Reproduces by seed (Swarbrick, Skarratt 1994) – sexual | l | h |
10. Number of propagules produced? | Unknown | m | l |
11. Propagule longevity? | Seedlings were found frequently growing two years after all standing vegetation had been cleared (Holmes, Cowling 1997) – greater than 25% of seeds survive at least 2 years | l | h |
12. Reproductive period? | Perrenial (AFFD 2008) – mature plant produces viable propagules for 3-10 years | mh | m |
13. Time to reproductive maturity? | Unknown | m | l |
Dispersal | |||
14. Number of mechanisms? | “Seeds spread by wind, water and in dumped garden waste” (Blood 2001) moderate rate of dispersal (Platt et al 2005) | mh | mh |
15. How far do they disperse? | “Seeds spread by wind, water and in dumped garden waste” (Blood 2001) – very likely to disperse greater than one kilometre | h | mh |