Present distribution
| Map Overlays Used Land Use: Pasture dryland on sandy soils. Broad vegetation types Coastal scrubs and grassland; coastal grassy woodland; grassland; plains grassy woodland; mallee; mallee heath; boinka-raak; mallee woodland; wimmera / mallee woodland (Restricted to sandy soils) Colours indicate possibility of Ehrharta villosa 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? | Can grow to 2m quite densely (Taylor 2004). | ml | mh |
| 2. Reduce tourism? | Changes the natural erosion patterns altering the character of coastal areas (Taylor 2004). | ml | m |
| 3. Injurious to people? | None described | l | m |
| 4. Damage to cultural sites? | Alters the natural erosion patterns of coastal and sandy areas (Taylor 2004). Changing the aesthetics of these areas. | ml | m |
| Abiotic | |||
| 5. Impact flow? | Terrestrial species | l | m |
| 6. Impact water quality? | Terrestrial species | l | m |
| 7. Increase soil erosion? | Used for sand stabilisation may even create problems for prevent natural levels erosion (Taylor 2004). | l | h |
| 8. Reduce biomass? | A dense mass of grass up to 2m high where there was previously sand, or more open vegetation (Taylor 2004). | l | mh |
| 9. Change fire regime? | Increasing the biomass, and also builds up large amounts of dead material increasing the fuel load potentially increasing the fire intensity (Taylor 2004). | ml | mh |
| Community Habitat | |||
| 10. Impact on composition (a) high value EVC | EVC= Plains Grassland (E); CMA= Mallee; Bioreg= Lowan Mallee; H CLIMATE potential. Can form monoculture in understorey. | h | mh |
| (b) medium value EVC | EVC= Shallow Sands Woodland (D); CMA= Mallee; Bioreg= Lowan Mallee; H CLIMATE potential. Can form monoculture in understorey. | h | mh |
| (c) low value EVC | EVC= Lowan Sands Mallee (LC); CMA= Mallee; Bioreg= Lowan Mallee; H CLIMATE potential. Can form monoculture in understorey. | h | mh |
| 11. Impact on structure? | Can smother out ephemerals and shrubs (Taylor 2004). | mh | mh |
| 12. Effect on threatened flora? | Can smother out species, and alters the erosion and disturbance pattens of the dune system (Taylor 2004). | mh | m |
| Fauna | |||
| 13. Effect on threatened fauna? | Alters the coastal habitat (Taylor 2004). | mh | ml |
| 14. Effect on non-threatened fauna? | Alters the habitat, potentially a reduction in food resources. | m | m |
| 15. Benefits fauna? | Dense grass would provide some shelter. | mh | m |
| 16. Injurious to fauna? | None reported | l | m |
| Pest Animal | |||
| 17. Food source to pests? | Not reported as food source for anything except galling nematode (Swart etal 2004). | l | mh |
| 18. Provides harbour? | Dense grass in sandy soil, prime habitat for rabbits. | h | ml |
| Agriculture | |||
| 19. Impact yield? | Not an agricultural weed, planted to reduce erosion and prevent further losses in soil fertility (Herriot 1944). | l | m |
| 20. Impact quality? | Not an agricultural weed, planted to reduce erosion and prevent further losses in soil fertility (Herriot 1944). | l | m |
| 21. Affect land value? | Not an agricultural weed, planted to reduce erosion and prevent further losses in soil fertility (Herriot 1944). | l | m |
| 22. Change land use? | Not an agricultural weed, planted to reduce erosion and prevent further losses in soil fertility (Herriot 1944). | l | m |
| 23. Increase harvest costs? | Not an agricultural weed. | l | m |
| 24. Disease host/vector? | Not an agricultural weed | l | m |
QUESTION | COMMENTS | RATING | CONFIDENCE |
| Establishment | |||
| 1. Germination requirements? | Not specified, little observations of seed production or seedlings. Has been planted using seeds, as well as rhizomes (Mort. & Hewitt. 1953). | m | l |
| 2. Establishment requirements? | If present can invade intact dune systems (Taylor 2004), this could include underneath a moderate canopy. | mh | m |
| 3. How much disturbance is required? | If present can invade intact dune systems (Taylor 2004). | mh | mh |
| Growth/Competitive | |||
| 4. Life form? | Perennial rhizomatous grass (Harrington, Hodder. & Outred. 1998) | mh | h |
| 5. Allelopathic properties? | None described, though heavy thatching from dead material can prevent seed germination of other species (Taylor 2004). | l | mh |
| 6. Tolerates herb pressure? | Herb pressure not described, Is tolerant of a galling nematode (Swart etal 2004). Is a grass species with a vigorous rhizome system (Harrington, Hodder. & Outred. 1998). | mh | m |
| 7. Normal growth rate? | Rhizomes have been recorded spreading 9m in a year, and are able to grow up surrounding vegetation smothering other ground species (Harrington, Hodder. & Outred. 1998). | h | h |
| 8. Stress tolerance to frost, drought, w/logg, sal. etc? | Present in coastal dunes, Tolerant of salinity. Drought Tolerant: can grow in areas of that receive only 25mm annual rainfall (Herriot 1944). Presumed fire tolerance rhizome system protected underground. | h | mh |
| Reproduction | |||
| 9. Reproductive system | Largely vegetative by rhizome spread, can set seed, however little has been seen in Australia and few to no seedlings have been observed (Harrington, Hodder. & Outred. 1998). | h | h |
| 10. Number of propagules produced? | Low seed set, less than one viable seed per seed head (Harrington, Hodder. & Outred. 1998). | ml | m |
| 11. Propagule longevity? | Unknown, however spread largely vegetative (Harrington, Hodder. & Outred. 1998). | l | ml |
| 12. Reproductive period? | Can form monocultures (Taylor 2004). | h | mh |
| 13. Time to reproductive maturity? | Can produce material for vegetative spread within first season (Harrington, Hodder. & Outred. 1998). | h | h |
| Dispersal | |||
| 14. Number of mechanisms? | Dispersal described largely by human means for erosion control. | m | l |
| 15. How far do they disperse? | Unknown, most reports associated with previous planting’s. | m | l |