Present distribution
| Map showing the present distribution of this weed. | ||||
Habitat: Annual herb (Ruiz de Clavijo 2002). Mallee cockspur occurs in areas with Mediterranean climates (Weeds In Australia 2007). It grows on calcareous soils and roadsides in open arid spaces (Ruiz de Clavijo 2002). ‘…It has been restricted to roadsides’ (Weeds In Australia 2007). ‘Centaurea is highly palatable to livestock and therefore do not invade grazed pastures’ (Cunningham and Brown 2006). |
Map Overlays Used Land Use: Broadacre cropping; horticulture perennial; horticulture seasonal; pasture dryland. Ecological Vegetation Divisions Coastal; heathland; grassy/heathy dry forest; lowland forest; foothills forest; forby forest; granitic hillslopes; rocky outcrop shrubland; semi-arid woodland; ironbark/box; chenopod shrubland; chenopod mallee; hummock-grass mallee; lowan mallee. Colours indicate possibility of Centaurea eriophora 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? | Centaurea eriophora is an annual herb growing to approximately 40cm tall, can grow to 70cm (Weeds in Australia 2007). Size of this plant is unlikely to greatly restrict access, but will cause minor hindrance. - Low nuisance value. Impedes individual access, unable to walk to waterways. | ml | m |
2. Reduce tourism? | Centaurea eriophora is an annual herb growing to approximately 40cm tall, can grow to 70cm (Weeds in Australia 2007). ‘This plant is a weed of pastures and rotational cropping’ (DPIW 2006). C. eriophora is unlikely to impact negatively upon tourism. - Potential minor effects to aesthetics. | ml | m |
3. Injurious to people? | No evidence of injurious characteristics. - No effect, no prickles, no injuries. | l | l |
4. Damage to cultural sites? | Centaurea eriophora is an annual herb growing to approximately 40cm tall, can grow to 70cm (Weeds in Australia 2007). ‘This plant is a weed of pastures and rotational cropping’ (DPIW 2006). C. eriophora is unlikely to impact negatively upon heritage/cultural sites. - Little or negligible effect on aesthetics or structure of site. | l | m |
Abiotic | |||
5. Impact flow? | Centaurea eriophora is an annual herb growing to approximately 40cm tall, can grow to 70cm (Weeds in Australia 2007). ‘…It has been restricted to roadsides and is not in adjacent paddocks’ (Weeds in Australia 2007). It grows on calcareous soils and roadsides in open arid spaces (Ruiz de Clavijo 2002). C. eriophora is not an aquatic weed nor does it grow on riparian zones, therefore unlikely to impact flows. - Little or negligible effect on water flow. | l | mh |
6. Impact water quality? | Centaurea eriophora is an annual herb growing to approximately 40cm tall, can grow to 70cm (Weeds in Australia 2007). ‘…It has been restricted to roadsides and is not in adjacent paddocks’ (Weeds in Australia 2007). It grows on calcareous soils and roadsides in open arid spaces (Ruiz de Clavijo 2002). C. eriophora is not an aquatic weed nor does it grow on riparian zones, therefore unlikely to impact water quality. - Little or negligible effect on water quality | l | mh |
7. Increase soil erosion? | ‘This plant is a weed of pastures and rotational cropping’ (DPIW 2006). Centaurea is highly palatable to livestock and therefore does not invade grazed pastures’ (Cunningham and Brown 2006). If C. eriophora is heavily grazed, it may leave bare patches of ground in pasture, therefore increasing chances of erosion, although exact impact on erosion rates is unknown. | m | l |
8. Reduce biomass? | ‘This plant is a weed of pastures and rotational cropping’ (DPIW 2006). Centaurea is highly palatable to livestock and therefore does not invade grazed pastures’ (Cunningham and Brown 2006). - Not enough information. | m | l |
9. Change fire regime? | No information. | m | l |
Community Habitat | |||
10. Impact on composition (a) high value EVC | EVC = Grassy Woodland (E); CMA = North Central; Bioregion = Goldfields. VH CLIMATE potential. Centaurea eriophora is an annual herb growing to approximately 40cm tall, can grow to 70cm (Weeds in Australia 2007). ‘Centaurea is highly palatable to livestock and therefore does not invade grazed pastures’ (Cunningham and Brown 2006). - Very little displacement of any indigenous species. Sparse and scattered infestations. | l | h |
(b) medium value EVC | EVC = Semi-arid woodland (D); CMA = Mallee; Bioregion = Lowan Mallee. VH CLIMATE potential. Centaurea eriophora is an annual herb growing to approximately 40cm tall, can grow to 70cm (Weeds in Australia 2007). ‘Centaurea is highly palatable to livestock and therefore does not invade grazed pastures’ (Cunningham and Brown 2006). - Minor displacement of some indicator species within any one strata or layer (e.g. ground layer, forbs, shrubs) | ml | h |
(c) low value EVC | EVC = Heathy Woodland (LC); CMA = Glenelg Hopkins; Bioregion = Wimmera. VH CLIMATE potential. Centaurea eriophora is an annual herb growing to approximately 40cm tall, can grow to 70cm (Weeds in Australia 2007). ‘Centaurea is highly palatable to livestock and therefore does not invade grazed pastures’ (Cunningham and Brown 2006). - Very little displacement of any indigenous species. Sparse and scattered infestations. | l | h |
11. Impact on structure? | Centaurea eriophora is an annual herb growing to approximately 40cm tall, can grow to 70cm (Weeds in Australia 2007). ‘Centaurea is highly palatable to livestock and therefore does not invade grazed pastures’ (Cunningham and Brown 2006). - Minor or negligible effect on <20% of the floral strata/layers present; usually only affecting one of the strata. | l | m |
12. Effect on threatened flora? | Centaurea eriophora is an annual herb growing to approximately 40cm tall, can grow to 70cm (Weeds in Australia 2007). - Impacts on threatened flora have not been measured. | mh | l |
Fauna | |||
13. Effect on threatened fauna? | ‘Centaurea is highly palatable to livestock and therefore does not invade grazed pastures’ (Cunningham and Brown 2006). Centaurea eriophora is an annual herb growing to approximately 40cm tall, can grow to 70cm (Weeds in Australia 2007). - Impact on threatened flora is unknown | mH | l |
14. Effect on non-threatened fauna? | ‘Centaurea is highly palatable to livestock and therefore does not invade grazed pastures’ (Cunningham and Brown 2006). Centaurea eriophora is an annual herb growing to approximately 40cm tall, can grow to 70cm (Weeds in Australia 2007). - No fauna affected due to fauna not co-existing within weed area or strata. | l | m |
15. Benefits fauna? | ‘Centaurea is highly palatable to livestock and therefore does not invade grazed pastures’ (Cunningham and Brown 2006). C eriophora is an annual herb growing to approximately 40cm tall, can grow to 70cm (Weeds in Australia 2007). This species may provide both shelter and a source of food to desirable species. C. eriophora possesses an elaisome, which is attractive to ants (Weeds in Australia 2007) - Provides some assistance in either food or shelter to desirable species. | mh | m |
16. Injurious to fauna? | No evidence of injurious characteristics. - No effect | l | l |
Pest Animal | |||
17. Food source to pests? | ‘Centaurea is highly palatable to livestock and therefore does not invade grazed pastures’ (Cunningham and Brown 2006). Commonly consumed by livestock, this species may also be consumed by important pest species. - Supplies food to serious pests (e.g. rabbits and foxes) but at low levels. | mh | m |
18. Provides harbor? | Centaurea eriophora is an annual herb growing to approximately 40cm tall, can grow to 70cm (Weeds in Australia 2007). At full height, there is potential for this species to provide cover for pest species. - May harbour rabbits and foxes at low densities or as overnight cover. | mh | m |
Agriculture | |||
19. Impact yield? | ‘This plant is a weed of pastures and rotational cropping’ (DPIW 2006). ‘Centaurea is highly palatable to livestock and therefore does not invade grazed pastures’ (Cunningham and Brown 2006). ‘Normal herbicide application may account for its apparent absence in crops.’ (Weeds in Australia 2007). C. eriophora is unlikely to impact yields; it is not known to be an agricultural contaminant and is kept under control by grazing and herbicide applications. - Little or negligible affect on quantity of yield. | l | m |
20. Impact quality? | This plant is a weed of pastures, rotational cropping (DPIW 2006). Centaurea is highly palatable to livestock and therefore do not invade grazed pastures’ (Cunningham and Brown 2006). Normal herbicide application may account for its apparent absence in crops (Weeds in Australia 2007). C. eriophora is unlikely to impact quality of produce; it is not known to be an agricultural contaminant and is kept under control by grazing and herbicide applications. - Little or negligible affect on quality of yield. | l | m |
21. Affect land value? | This plant is a weed of pastures, rotational cropping (DPIW 2006). Centaurea is highly palatable to livestock and therefore do not invade grazed pastures’ (Cunningham and Brown 2006). Normal herbicide application may account for its apparent absence in crops (Weeds in Australia 2007). C. eriophora is unlikely to affect value of land as it is not a problematic invasive weed. It is controlled naturally by grazing and also herbicides. - Little or none. | l | m |
22. Change land use? | This plant is a weed of pastures, rotational cropping (DPIW 2006). Centaurea is highly palatable to livestock and therefore do not invade grazed pastures’ (Cunningham and Brown 2006). Normal herbicide application may account for its apparent absence in crops (Weeds in Australia 2007). This species is unlikely to cause a change in land use as it is kept ‘under control’ by grazing and herbicide applications. - Little or none. | l | m |
23. Increase harvest costs? | This plant is a weed of pastures, rotational cropping (DPIW 2006). Centaurea is highly palatable to livestock and therefore do not invade grazed pastures’ (Cunningham and Brown 2006). Normal herbicide application may account for its apparent absence in crops (Weeds in Australia 2007). Evidence suggests that only minor effort will be needed to keep this weed under control, as it is maintained by normal herbicide application and also grazing. - Little or none. | l | m |
24. Disease host/vector? | Not a host according to Plant Viruses Online (Brunt et al. 1996) - Little or no host. | l | m |
QUESTION | COMMENTS | RATING | CONFIDENCE |
Establishment | |||
1. Germination requirements? | Annual herb (Ruiz de Clavijo 2002). Centaurea eriophora occurs in areas with Mediterranean climates (Weeds in Australia 2008). It grows on calcareous soils and roadsides in open arid spaces (Ruiz de Clavijo 2002). - Requires natural seasonal disturbances such as seasonal rainfall, spring/summer temperatures for germination. | mh | m |
2. Establishment requirements? | Annual herb, growing on calcareous soils and roadsides in open arid spaces (Ruiz de Clavijo 2002). - Requires more specific requirements to establish (e.g. open space or bare ground). | ml | m |
3. How much disturbance is required? | ‘…It has been restricted to roadsides and is not in adjacent paddocks’ (Weeds in Australia 2008). It grows on calcareous soils and roadsides in open arid spaces (Ruiz de Clavijo 2002). - Establishes in highly disturbed natural ecosystems (e.g. roadsides wildlife corridors, or areas which have greater impact by humans such as tourist areas or campsites). | ml | mh |
Growth/Competitive | |||
4. Life form? | Annual herb (Ruiz de Clavijo 2002) - Other. | L | m |
5. Allelopathic properties? | None described (Rice 1984). - None. | l | m |
6. Tolerates herb pressure? | ‘Centaurea is highly palatable to livestock and therefore do not invade grazed pastures’ (Cunningham and Brown 2006). - Consumed and recovers slowly. Reproduction strongly inhibited by herbivory but still capable of vegetative propagule production (by rhizomes or tubers); weed may still persist. | ml | m |
7. Normal growth rate? | Growth rate unknown. | m | l |
8. Stress tolerance to frost, drought, w/logg, sal. etc? | Grows on open arid spaces (Ruiz de Clavijo 2002). This species is probably tolerant of drought, according to habitat preference, although tolerances to other stresses were not found. - May be tolerant of one stress, susceptible to at least two. | l | mh |
Reproduction | |||
9. Reproductive system | Reproduction is via seed (Ruiz de Clavijo 2002). No evidence of vegetative reproduction. - Sexual (either cross or self pollination). | l | h |
10. Number of propagules produced? | Each flower can produce one seed. ‘Centaurea eriophora is likely to be a prolific seeder like closely related species’ (Weeds in Australia 2008). - 50-1000 | ml | m |
11. Propagule longevity? | Unknown. | m | l |
12. Reproductive period? | Annual herb (Ruiz de Clavijo 2002) - Mature plant produces viable propagules for only one year. | l | m |
13. Time to reproductive maturity? | Annual herb (Ruiz de Clavijo 2002) - Reaches maturity and produces viable propagules or vegetative propagules become separate individuals in under a year. | h | m |
Dispersal | |||
14. Number of mechanisms? | ‘Achenes of C. eriophora are avidly carried off by ants, attracted to the elaiosome at the base of the achene’ (Witztum e al. 1996). C. eriophora also possesses a pappus, which is adapted for wind dispersal, but studies show that this structure is not efficient as a seed dispersal mechanism (Imbert 2006; Witztum et al.1996). ‘Course pappus bristles may also aid dispersal by clinging to animals or machinery (Weeds in Australia 2008) - Propagules spread by attachment (ants, animal fur and machinery) and to a lesser degree wind. | mh | mh |
15. How far do they disperse? | ‘Achenes of C. eriophora do not fall far from the mother plant.’ (Witztum et al. 1996). ‘… [Achenes] are unlikely to be dispersed over long distances by the wind’ (Ruiz de Clavijo 2002). - Very few to none will disperse to one kilometre, most 20-200 metres. | ml | mh |