Pacific Island Ecosystems at Risk (PIER)
RISK ASSESSMENT RESULTS: Reject, Score: 6
Note: Risk assessment prepared for Australia
Information on Risk Assessments
Wedelia trilobata | ||||
A. | Biogeography/ | wedelia | ||
historical | Leguminosae | P&R | ||
1 | Domestication/ | 1.01 | Is the species highly domesticated? | |
cultivation | 1.02 | Has the species become naturalised where grown? | ||
1.03 | Does the species have weedy races? | |||
2 | Climate and | 2.01 | Species suited to Australian climates (0-low; 1-intermediate; 2-high) | 2 |
Distribution | 2.02 | Quality of climate match data (0-low; 1-intermediate; 2-high) | 1 | |
2.03 | Broad climate suitability (environmental versatility) | N | ||
2.04 | Native or naturalised in regions with extended dry periods | N | ||
2.05 | Does the species have a history of repeated introductions outside its natural range? | Y | ||
3 | Weed | 3.01 | Naturalised beyond native range | Y |
Elsewhere | 3.02 | Garden/amenity/disturbance weed | Y | |
(interacts with 2.01 | 3.03 | Weed of agriculture | ||
to give a weighted | 3.04 | Environmental weed | ||
score) | 3.05 | Congeneric weed | Y | |
B. | Biology/Ecology | |||
4 | Undesirable | 4.01 | Produces spines, thorns or burrs | N |
traits | 4.02 | Allelopathic | ||
4.03 | Parasitic | N | ||
4.04 | Unpalatable to grazing animals | N | ||
4.05 | Toxic to animals | |||
4.06 | Host for recognised pests and pathogens | |||
4.07 | Causes allergies or is otherwise toxic to humans | N | ||
4.08 | Creates a fire hazard in natural ecosystems | N | ||
4.09 | Is a shade tolerant plant at some stage of its life cycle | |||
4.10 | Grows on infertile soils | |||
4.11 | Climbing or smothering growth habit | N | ||
4.12 | Forms dense thickets | N | ||
5 | Plant | 5.01 | Aquatic | N |
type | 5.02 | Grass | N | |
5.03 | Nitrogen fixing woody plant | N | ||
5.04 | Geophyte | N | ||
6 | Reproduction | 6.01 | Evidence of substantial reproductive failure in native habitat | |
6.02 | Produces viable seed. | Y | ||
6.03 | Hybridises naturally | |||
6.04 | Self-compatible or apomictic | |||
6.05 | Requires specialist pollinators | |||
6.06 | Reproduction by vegetative fragmentation | Y | ||
6.07 | Minimum generative time (years) | 1 | ||
7 | Dispersal mechanisms | 7.01 | Propagules likely to be dispersed unintentionally (plants growing in areas with much vehicle movement) | N |
7.02 | Propagules dispersed intentionally by people | Y | ||
7.03 | Propagules likely to disperse as a produce contaminant | N | ||
7.04 | Propagules adapted to wind dispersal | N | ||
7.05 | Propagules water dispersed | |||
7.06 | Propagules bird dispersed | |||
7.07 | Propagules dispersed by other animals (externally) | |||
7.08 | Propagules survive passage through the gut | |||
8 | Persistence | 8.01 | Prolific seed production (>2000/m2) | N |
attributes | 8.02 | Evidence that a persistent propagule bank is formed (>1 yr) | ||
8.03 | Well controlled by herbicides | |||
8.04 | Tolerates, or benefits from, mutilation or cultivation | Y | ||
8.05 | Effective natural enemies present in Australia | |||
Outcome: | Reject | |||
Score: | 6 | |||
Statistical summary | Biogeography | 6 | ||
of scoring | Score partition: Undesirable attributes | -1 | ||
Biology/ecology | 1 | |||
Biogeography | 5 | |||
Questions answered: Undesirable attributes | 7 | |||
Biology/ecology | 13 | |||
Total | 25 | |||
Agricultural | 4 | |||
Sector affected: Environmental | 5 | |||
Nusiance | 2 | |||
A= agricultural, E = environmental, N = nuisance, C=combined |
Risk assessment prepared by Paul Pheloung and Rod Randall
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This page new 26 January 2001.