Present distribution
| This weed is not known to be naturalised in Victoria | ||||
Habitat: Naturalised in hillside scrub in NZ (Webb et al 1988), “in ravines and on cliffs, usually along streams or in damp places” (Van Wyk, Van Wyk 1997) also occur on the margins of woodlands (Elliot 1999). In its native range it is dominant in riparian scrub in open and closed habitats (Galatowitsch, Richardson 2005). Mixed sands and clays (Helme 2007), in soils that are seasonally waterlogged and very dry in the summer (Helme 2007). |
Map Overlays Used Land Use: Forestry; horticulture perennial; pasture irrigation Ecological Vegetation Divisions Coastal; heathland; swampy scrub; freshwater wetland (permanent); treed swampy wetland; lowland forest; foothills forest; forby forest; damp forest; riparian; high altitude wetland; granitic hillslopes; western plains woodland; basalt grassland; alluvial plains grassland; alluvial plains woodland; ironbark/box; riverine woodland/forest; freshwater wetland (ephemeral) Colours indicate possibility of Erica caffra 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? | Grows to 3m (New Zealand Plant Conservation Network 2005) in riparian areas (Galatowitsch, Richardson 2005) – high nuisance value. People and/or vehicles access with difficulty | mh | mh |
2. Reduce tourism? | Grows to 3m and has white, occasionally pink flowers (New Zealand Plant Conservation Network 2005) and is dominant in riparian areas (Galatowitsch, Richardson 2005) – some recreation uses could be affected | mh | mh |
3. Injurious to people? | No mention of injurious properties (Van Wyk, Van Wyk 1997) – no effect | l | mh |
4. Damage to cultural sites? | Grows to 3m and has white, occasionally pink flowers (New Zealand Plant Conservation Network 2005) – may have moderate visual effects | ml | m |
Abiotic | |||
5. Impact flow? | Riparian pioneer (Galatowitsch, Richardson 2005), but does not grow in the water – little or negligible affect on water flow | l | h |
6. Impact water quality? | Riparian pioneer (Galatowitsch, Richardson 2005) and grows to 3m (New Zealand Plant Conservation Network 2005) – may have noticeable effects on light levels | ml | mh |
7. Increase soil erosion? | As it is an evergreen shrub (New Zealand Plant Conservation Network 2005) there is low probability of large scale soil movement | l | m |
8. Reduce biomass? | “tolerate open habitats favoured by alien trees, eventually forming closed canopies required by shade-tolerant species” (Galatowitsch, Richardson 2005) – increase biomass | l | h |
9. Change fire regime? | “Tolerate open habitats favoured by alien trees, eventually forming closed canopies required by shade-tolerant species” (Galatowitsch, Richardson 2005). It is also dominant in a vegetation community that survives fire (Vogelgat Private Nature Reserve 2005) – greatly changes the frequency and intensity of fire risk | h | mh |
Community Habitat | |||
10. Impact on composition (a) high value EVC | EVC = Redgum Wetland (V); CMA = Wimmera; Bioregion = Wimmera; VH CLIMATE potential “tolerate open habitats favoured by alien trees, eventually forming closed canopies required by shade-tolerant species” (Galatowitsch, Richardson 2005) -Monoculture within a specific layer; displaces all spp. within a strata/layer | h | h |
(b) medium value EVC | EVC = Valley Grassy Forest (D); CMA = East Gippsland; Bioregion = East Gippsland Lowlands; VH CLIMATE potential “tolerate open habitats favoured by alien trees, eventually forming closed canopies required by shade-tolerant species” (Galatowitsch, Richardson 2005) – Monoculture within a specific layer; displaces all spp. within a strata/layer | h | h |
(c) low value EVC | EVC = Wet Heathland (LC); CMA = Glenelg Hopkins; Bioregion = Glenelg Plain; VH CLIMATE potential “tolerate open habitats favoured by alien trees, eventually forming closed canopies required by shade-tolerant species” (Galatowitsch, Richardson 2005)- Monoculture within a specific layer; displaces all spp. within a strata/layer | h | h |
11. Impact on structure? | “tolerate open habitats favoured by alien trees, eventually forming closed canopies required by shade-tolerant species” (Galatowitsch, Richardson 2005) – may invade open areas, therefore may effect all layers | h | h |
12. Effect on threatened flora? | Not known to threaten Priority 1A spp. or VROT spp. | mh | l |
Fauna | |||
13. Effect on threatened fauna? | Not known to threaten VROT or Bioregional Priority spp. | mh | l |
14. Effect on non-threatened fauna? | “tolerate open habitats favoured by alien trees, eventually forming closed canopies required by shade-tolerant species” (Galatowitsch, Richardson 2005) – capacity to change habitat dramatically, leading to the possible extinction of non-threatened fauna | h | h |
15. Benefits fauna? | No information on palatability, however it is a shrub to 3 m (New Zealand Plant Conservation Network 2005), therefore is likely to provide some assistance in shelter to desirable species | mh | m |
16. Injurious to fauna? | No mention of injurious properties (Van Wyk, Van Wyk 1997) – no effect | l | mh |
Pest Animal | |||
17. Food source to pests? | Rabbits sometimes feed on young Erica spp. plants (Underhill 1971) – likely to supply food for a serious pest | mh | mh |
18. Provides harbor? | Rabbits sometimes burrow underneath Erica spp. plants (Underhill 1971) – capacity to provide harbour and permanent warrens for foxes and rabbits throughout the year | h | mh |
Agriculture | |||
19. Impact yield? | Not listed as a weed of agriculture (Randall 2007) – impact on yield unknown | m | l |
20. Impact quality? | Not listed as a weed of agriculture (Randall 2007) – impact on quality unknown | m | l |
21. Affect land value? | Not listed as a weed of agriculture (Randall 2007) – impact on land value unknown | m | l |
22. Change land use? | Not listed as a weed of agriculture (Randall 2007) – impact on priority of land use unknown | m | l |
23. Increase harvest costs? | “tolerate open habitats favoured by alien trees, eventually forming closed canopies required by shade-tolerant species” (Galatowitsch, Richardson 2005) – if this invades pastureland and forestry plantations, clearing may be required before harvest – minor increase in cost of harvesting | m | m |
24. Disease host/vector? | Plants belonging to the Erica genus “are eaten by the larvae of some Lepidoptera species” (Art Immersion 2008) – provides host to common pests | m | ml |
QUESTION | COMMENTS | RATING | CONFIDENCE |
Establishment | |||
1. Germination requirements? | “Smoke treatment is essential in the propagation of nearly all South African Ericas” (Garden Web 2008) – requires unseasonal or uncommon natural events for germination | ml | ml |
2. Establishment requirements? | Dominant in riparian scrub in both open and closed habitats (Galatowitsch, Richardson 2005) – can establish without additional factors | h | h |
3. How much disturbance is required? | Occurs “in ravines and on cliffs, usually along streams or in damp places” (Van Wyk, Van Wyk 1997) and “on the margins of woodlands on Bruny Island” (Elliot 1999). Dominant in riparian scrub in both open and closed habitats (Galatowitsch, Richardson 2005) – establishes in relatively natural ecosystems | mh | mh |
Growth/Competitive | |||
4. Life form? | Shrub (Elliot 1999) | l | h |
5. Allelopathic properties? | No literature that identifies E. caffra as allelopathic, however other Erica spp., such as E. cinerea, E. mediterranea, and E. scoparia, have allelopathic properties affecting some crops (Rice 1984). Therefore there is a chance that the allelopathic properties are as yet unknown | m | l |
6. Tolerates herb pressure? | Plants belonging to the Erica genus “are eaten by the larvae of some Lepidoptera species” (Art Immersion 2008), however no information on its recovery, or specific to the species | m | l |
7. Normal growth rate? | Dominant species (Vogelgat Private Nature Reserve 2005) – 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? | Grows where frosts “occur most nights from march to September” in South Africa (Scott et al 2005) Dominant in a vegetation community that survives fire (Vogelgat Private Nature Reserve 2005) Grows in soils that are seasonally waterlogged and very dry in the summer (Helme 2007) Tolerant to frost, fire, water logging and may be tolerant to drought. | h | m |
Reproduction | |||
9. Reproductive system | By seed (New Zealand Plant Conservation Network 2005) – sexual reproduction | ml | m |
10. Number of propagules produced? | “many seeds are produced” (New Zealand Plant Conservation Network 2005) and large plants of Eric cinerea can produce tens of thousands of seeds per year (Soons, Bullock 2008), up to 1.2 million (Bullock, Moy 2004) – likely to produce over 2000 per flowering event | h | m |
11. Propagule longevity? | Although seeds of Erica cinerea can survive for 30 – 40 years in the soil seed bank (Turner, Conran 2004), it the propagule longevity for E. caffra is unknown | m | L |
12. Reproductive period? | Unknown | m | l |
13. Time to reproductive maturity? | Unknown | m | l |
Dispersal | |||
14. Number of mechanisms? | Dispersed by people and gravity (New Zealand Plant Conservation Network 2005). The seeds are also very easily scattered by wind, as 50,000 E. caffra seeds weigh one gram (Marloth 1932) – very light wind dispersed | h | m |
15. How far do they disperse? | Dispersal by people (New Zealand Plant Conservation Network 2005) may result in dispersal greater that 1 km | h | m |