Present distribution
| Map showing the present distribution of this weed. | ||||
Habitat: Naturalised in montane grasslands (Pemadasa 1981), disturbed bushland, along roadsides (Richardson et al. 2006), riparian, dry sclerophyll forest/woodland (Csurhes, Edwards 1998), shrubland/scrub, urban/open space (Auckland Regional Council 2002), tracks, open forest e.g. kauri (Auckland Regional Council 2007), upper montane rain forest (Rathnayake, Jayasekera 1998), wetlands, estuaries, coastal grassland (TEM 2007), exposed areas near the shoreline, up to the dunes. Salt tolerant (Llamas 2003), drought tolerant (Diggers Club 2008). |
Map Overlays Used Land Use: Forestry; pasture dryland; pasture irrigation Ecological Vegetation Divisions Coastal; heathland; grassy/heathy dry forest; swampy scrub; freshwater wetland (permanent); treed swampy wetland; lowland forest; foothills forest; forby forest; damp forest; riparian; wet forest; rainforest; high altitude shrubland/woodland; high altitude wetland; alpine treeless; granitic hillslopes; rocky outcrop shrubland; western plains woodland; basalt grassland; alluvial plains grassland; semi-arid woodland; alluvial plains woodland; ironbark/box; riverine woodland/forest; freshwater wetland (ephemeral); saline wetland Colours indicate possibility of Aristea ecklonii 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? | Herbaceous to 70 cm (Richardson et al. 2006) - Minimal OR negligible impact (ie. can go anywhere). | l | mh |
2. Reduce tourism? | Grows to 70 cm, with blue flowers, in bushland (Richardson et al. 2006), grasslands (Pemadasa 1981), and rain forest (Rathnayake, Jayasekera 1998) - Minor effects to aesthetics AND/OR recreational uses (ie. aware but not bothered or activity inhibited). | ml | mh |
3. Injurious to people? | Not known to have injurious properties; not mentioned in the literature (Csurhes 2008; Richardson et al. 2006) - No effect, no prickles, no injuries. | l | mh |
4. Damage to cultural sites? | Grows to 70 cm, with blue flowers, in bushland (Richardson et al. 2006), grasslands (Pemadasa 1981), and rain forest (Rathnayake, Jayasekera 1998) – may have a moderate visual effect in historic gardens and natural cultural sites. | ml | mh |
Abiotic | |||
5. Impact flow? | Terrestrial (Richardson et al. 2006) - Little or negligible affect on water flow. | l | mh |
6. Impact water quality? | Terrestrial (Richardson et al. 2006) - No noticeable effect on dissolved 02 OR light levels. | l | mh |
7. Increase soil erosion? | Rhizomatous perennial (Pretorius et al. 2002) - Low probability of large scale soil movement; OR decreases the probability of soil erosion. | l | mh |
8. Reduce biomass? | Grows to 70 cm in bushland (Richardson et al. 2006), grasslands (Pemadasa 1981), rainforest (Rathnayake, Jayasekera 1998), and forms dense stands (Csurhes 2008). “Forms dense, long-lived stands… preventing the seedlings of native species from establishing. Opens up the canopy, leading to further invasion by weedy shrubs, vines and grasses” (Weedbusters 2009) - Biomass significantly decreased (eg. trees replaced by more open community). | h | mh |
9. Change fire regime? | Herbaceous perennial that grows to 70 cm in bushland (Richardson et al. 2006), grasslands (Pemadasa 1981), rainforest (Rathnayake, Jayasekera 1998). “Forms dense, long-lived stands… preventing the seedlings of native species from establishing. Opens up the canopy, leading to further invasion by weedy shrubs, vines and grasses” (Weedbusters 2009) - Greatly changes the frequency AND/OR intensity of fire risk. | h | mh |
Community Habitat | |||
10. Impact on composition (a) high value EVC | EVC = Damp Forest (E); CMA = West Gippsland; Bioregion = Strzelecki Ranges; VH CLIMATE potential. Herbaceous perennial that grows to 70 cm in bushland (Richardson et al. 2006), grasslands (Pemadasa 1981), rainforest (Rathnayake, Jayasekera 1998), forming dense stands (Csurhes 2008). “Extensive patches out-compete native species” (Auckland Regional Council 2007). “Forms dense, long-lived stands… preventing the seedlings of native species from establishing. Opens up the canopy, leading to further invasion by weedy shrubs, vines and grasses” (Weedbusters 2009) Monoculture within a specific layer; displaces all spp. within a strata/layer | h | h |
(b) medium value EVC | EVC = Sedgey Riparian Woodland (D); CMA = Corangamite; Bioregion = Central Victorian Uplands; VH CLIMATE potential. Herbaceous perennial that grows to 70 cm in bushland (Richardson et al. 2006), grasslands (Pemadasa 1981), rainforest (Rathnayake, Jayasekera 1998), forming dense stands (Csurhes 2008). “Extensive patches out-compete native species” (Auckland Regional Council 2007). “Forms dense, long-lived stands… preventing the seedlings of native species from establishing. Opens up the canopy, leading to further invasion by weedy shrubs, vines and grasses” (Weedbusters 2009) Monoculture within a specific layer; displaces all spp. within a strata/layer | h | h |
(c) low value EVC | EVC = Wet Forest (LC); CMA = West Gippsland; Bioregion = Highlands – Southern Fall; VH CLIMATE potential. Herbaceous perennial that grows to 70 cm in bushland (Richardson et al. 2006), grasslands (Pemadasa 1981), rainforest (Rathnayake, Jayasekera 1998), forming dense stands (Csurhes 2008). “Extensive patches out-compete native species” (Auckland Regional Council 2007). “Forms dense, long-lived stands… preventing the seedlings of native species from establishing. Opens up the canopy, leading to further invasion by weedy shrubs, vines and grasses” (Weedbusters 2009) Monoculture within a specific layer; displaces all spp. within a strata/layer | h | h |
11. Impact on structure? | Herbaceous perennial that grows to 70 cm in bushland (Richardson et al. 2006), grasslands (Pemadasa 1981), rainforest (Rathnayake, Jayasekera 1998), forming dense stands (Csurhes 2008). “Extensive patches out-compete native species” (Auckland Regional Council 2007). In Sri Lanka it was found that “the total relative frequencies of endemic and exotic species [including A. ecklonii] were nearly same in the understorey vegetation” in upper montane rain forest at 1600 m and 1800 m (Rathnayake, Jayasekera 1998). “Forms dense, long-lived stands… preventing the seedlings of native species from establishing. Opens up the canopy, leading to further invasion by weedy shrubs, vines and grasses” (Weedbusters 2009). - Major effect on < 60% of the floral strata. | mh | mh |
12. Effect on threatened flora? | “Forms dense, long-lived stands… preventing the seedlings of native species from establishing. Opens up the canopy, leading to further invasion by weedy shrubs, vines and grasses” (Weedbusters 2009). However it is not yet known to effect any population of Bioregional Priority 1A or VROT spp. | mh | l |
Fauna | |||
13. Effect on threatened fauna? | “Forms dense, long-lived stands… preventing the seedlings of native species from establishing. Opens up the canopy, leading to further invasion by weedy shrubs, vines and grasses” (Weedbusters 2009). However it is not yet known to effect any population of Bioregional Priority or VROT spp. | mh | l |
14. Effect on non-threatened fauna? | Herbaceous perennial that grows to 70 cm in bushland (Richardson et al. 2006), grasslands (Pemadasa 1981), rainforest (Rathnayake, Jayasekera 1998), forming dense stands (Csurhes 2008). “Extensive patches out-compete native species” (Auckland Regional Council 2007). In Sri Lanka it was found that “the total relative frequencies of endemic and exotic species [including A. ecklonii] were nearly same in the understorey vegetation” in upper montane rain forest at 1600 m and 1800 m (Rathnayake, Jayasekera 1998) - Reduction in habitat for fauna spp., leading to reduction in numbers of individuals, but NOT to local extinction. | mh | mh |
15. Benefits fauna? | Eaten by mountain baboons (Byrne et al. 1993) – may provide some assistance in food to desirable species | mh | m |
16. Injurious to fauna? | Not known to have injurious properties; not mentioned in the literature (Csurhes 2008; Richardson et al. 2006) - No effect. | l | mh |
Pest Animal | |||
17. Food source to pests? | “Pollination of species with these flowers is, as far as known, by pollen-collecting female bees of the families Anthophoridae, Halictidae, and as is often the case in Africa, Apis mellifera” (Goldblatt, Le Thomas 1997) – supplies food for one or more minor pest spp. | ml | m |
18. Provides harbor? | Herbaceous perennial that grows to 70 cm (Richardson et al. 2006) and forms dense stands (Csurhes 2008) - Capacity to harbor rabbits or foxes at low densities or as overnight cover. | mh | mh |
Agriculture | |||
19. Impact yield? | Not listed as an agricultural weed (Randall 2007), however it does occur in grasslands (Pemadasa 1981), and Csurhes (2007) predicts pasture incursions in Queensland – potential to have an impact on pasture yield, however to what is extent is unknown | m | l |
20. Impact quality? | Not listed as an agricultural weed (Randall 2007), however it does occur in grasslands (Pemadasa 1981), and Csurhes (2007) predicts pasture incursions in Queensland – potential to have an impact on pasture quality, however to what is extent is unknown | m | l |
21. Affect land value? | Not listed as an agricultural weed (Randall 2007) - not likely to affect land value | l | m |
22. Change land use? | “Difficult to eradicate once established as seeds prolifically. Clear roadsides, tracks and streamsides first, then move into bush” (Auckland Regional Council 2007) – may cause downgrading of the priority land use, to one with either less agricultural return. | mh | m |
23. Increase harvest costs? | Although it is not listed as an agricultural weed (Randall 2007) it is “difficult to eradicate once established as seeds prolifically.” (Auckland Regional Council 2007) – may increase harvest cost, however to what extent is unknown. | m | l |
24. Disease host/vector? | “The crude extract of A ecklonii performed best of all extracts as it totally inhibited the mycetial growth of all seven of the plant pathogenic test organisms and outperformed the inhibition by a broad spectrum synthetic fungicide” (Pretorius et al. 2002) - Little or no host. | l | h |
QUESTION | COMMENTS | RATING | CONFIDENCE |
Establishment | |||
1. Germination requirements? | “The elongate, leathery-woody, tardily dehiscent capsules of section Pseudaristea [including A. ecklonii] suggest another strategy for survival in the southern African winter-rainfall zone. Flowering occurs from September to November in the various species, but the seeds are not shed for at least six months after ripening and thus are held in the hard-walled capsules until the rainy season, which begins in April or May. The capsules decay under wet conditions and then release their seeds at a time most favourable for germination. The tough capsules presumable serve as a protection from both desiccation and insect predation during the long period that the seeds are retained.” (Goldblatt, Le Thomas 1997) – requires natural seasonal disturbances such as seasonal rainfall | mh | h |
2. Establishment requirements? | Naturalised in upper montane rain forest in Hakgala Strict Nature Reserve in Sri Lanka (Rathnayake, Jayasekera 1998) – can establish without additional factors. | h | h |
3. How much disturbance is required? | Found in turves in montane grasslands in Sri Lanka (Pemadasa 1981). “Occasionally found in disturbed bushland and along roadsides” (Richardson et al. 2006). “Isolated, small naturalised populations exist in Victoria, where it is considered to pose a threat to riparian vegetation and dry sclerophyll forest/woodland. Small naturalised populations exist on the central coast of New South Wales in disturbed woodland and the Sydney area” (Csurhes, Edwards 1998). Habitats: “Roadsides, tracks, open forest e.g. kauri, in extensive patches. Most common in North Auckland” (Auckland Regional Council 2007). Naturalised in upper montane rain forest in Hakgala Strict Nature Reserve in Sri Lanka (Rathnayake, Jayasekera 1998) - Establishes in healthy AND undisturbed natural ecosystems (e.g. mallee, alpine, heathland). | h | h |
Growth/Competitive | |||
4. Life form? | Rhizomes (Kumar et al. 1985), corms (Larsen et al. 1987) – geophyte | ml | h |
5. Allelopathic properties? | Not known to have allelopathic properties (Qasem, Foy 2001; Rice 1984) – none | l | m |
6. Tolerates herb pressure? | Eaten by mountain baboons (Byrne et al. 1993) – consumed but not preferred | mh | ml |
7. Normal growth rate? | “Extensive patches out-compete native species” (Auckland Regional Council 2007) – 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? | Drought tolerant (Diggers Club 2008). Listed as a “species with moderate to excellent salt tolerance” that “thrive in exposed areas near the shoreline, some right up to the dunes” (Llamas 2003). Occur in wetlands, estuaries, and coastal grassland after being burnt (TEM 2007) – highly resistant of fire, waterlogging, salinity and drought. | h | m |
Reproduction | |||
9. Reproductive system | Rhizomes (Kumar et al. 1985), corms (Larsen et al. 1987), seeds (Csurhes, Edwards 1998) - Both vegetative AND sexual reproduction. | h | mh |
10. Number of propagules produced? | “Numerous small seeds dispersed by water” (Csurhes, Edwards 1998) – above 2000 | h | m |
11. Propagule longevity? | Unknown | m | l |
12. Reproductive period? | “Forms dense, long-lived stands” (Weedbusters 2009) - Mature plant produces viable propagules for 10 years or more, OR species forms self-sustaining monocultures. | h | ml |
13. Time to reproductive maturity? | Unknown | m | l |
Dispersal | |||
14. Number of mechanisms? | “Numerous small seeds dispersed by water” (Csurhes, Edwards 1998). “Seeds prolifically, dispersed by wind or gravity” (Auckland Regional Council 2007) | h | m |
15. How far do they disperse? | “Numerous small seeds dispersed by water” (Csurhes, Edwards 1998). “Seeds prolifically, dispersed by wind or gravity” (Auckland Regional Council 2007) – very likely that at least one propagule will disperse greater than one kilometre. | h | m |