Pacific Island Ecosystems at Risk (PIER)

Acmella grandiflora


Australian/New Zealand Weed Risk Assessment adapted for Hawai‘i.
Information on Risk Assessments
Original risk assessment
  Acmella grandiflora Family- Asteraceae Answer Score
1.01 Is the species highly domesticated? (If answer is 'no' then go to question 2.01) n 0
1.02 Has the species become naturalized where grown?    
1.03 Does the species have weedy races?    
2.01 Species suited to tropical or subtropical climate(s) (0-low; 1-intermediate; 2-high) – If island is primarily wet habitat, then substitute “wet tropical” for “tropical or subtropical” 2  
2.02 Quality of climate match data (0-low; 1-intermediate; 2-high)                 see appendix 2 2  
2.03 Broad climate suitability (environmental versatility)    
2.04 Native or naturalized in regions with tropical or subtropical climates y 1
2.05 Does the species have a history of repeated introductions outside its natural range?  y=-2 y  
3.01 Naturalized beyond native range         y = 1*multiplier (see Append 2), n= question 2.05 n -2
3.02 Garden/amenity/disturbance weed                              y = 1*multiplier (see Append 2) n 0
3.03 Agricultural/forestry/horticultural weed                         y = 2*multiplier (see Append 2) n 0
3.04 Environmental weed                                                     y = 2*multiplier (see Append 2) n 0
3.05 Congeneric weed                                                          y = 1*multiplier (see Append 2) y 2
4.01 Produces spines, thorns or burrs n 0
4.02 Allelopathic n 0
4.03 Parasitic n 0
4.04 Unpalatable to grazing animals    
4.05 Toxic to animals n 0
4.06 Host for recognized pests and pathogens    
4.07 Causes allergies or is otherwise toxic to humans n 0
4.08 Creates a fire hazard in natural ecosystems n 0
4.09 Is a shade tolerant plant at some stage of its life cycle    
4.1 Tolerates a wide range of soil conditions (or limestone conditions if not a volcanic island)    
4.11 Climbing or smothering growth habit n 0
4.12 Forms dense thickets n 0
5.01 Aquatic n 0
5.02 Grass n 0
5.03 Nitrogen fixing woody plant n 0
5.04 Geophyte (herbaceous with underground storage organs -- bulbs, corms, or tubers) n 0
6.01 Evidence of substantial reproductive failure in native habitat n 0
6.02 Produces viable seed.    
6.03 Hybridizes naturally    
6.04 Self-compatible or apomictic    
6.05 Requires specialist pollinators n 0
6.06 Reproduction by vegetative fragmentation    
6.07 Minimum generative time (years)                 1 year = 1, 2 or 3 years = 0, 4+ years = -1 1 1
7.01 Propagules likely to be dispersed unintentionally (plants growing in heavily trafficked areas) n -1
7.02 Propagules dispersed intentionally by people y 1
7.03 Propagules likely to disperse as a produce contaminant    
7.04 Propagules adapted to wind dispersal y 1
7.05 Propagules water dispersed n -1
7.06 Propagules bird dispersed n -1
7.07 Propagules dispersed by other animals (externally)    
7.08 Propagules survive passage through the gut n -1
8.01 Prolific seed production (>1000/m2)    
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, cultivation, or fire    
8.05 Effective natural enemies present locally (e.g. introduced biocontrol agents)    
  Total score:   0

Supporting data:

  Notes Reference
1.01 No evidence  
2.01 (1)Native to New South Wales (Australia).  (2)Endemic to Northern Territory in Australia.  (3)Regarded as rare in NSW by Sheringhan and Westaway (1995). Scarce and occurs in low lying Red Gum and Paperbark forest on seasonally waterlogged soild in the region between the Richmond and Clarence rivers. A singel plant was seen in the Paperbark community on lower Moonee Creek, which may represent the extreme southern limit of its range." (1)  (2)   (3)
2.02 Occurs in Indonesia and Phillipines.
2.03 No evidence regarding the environmental versatility of this species.  
2.04 (1)Native to New South Wales (Australia).  (2)Endemic to Northern Territory in Australia. (1)  (2)
2.05 Occurs in Indonesia and Phillipines.
3.01 No evidence of naturalization.  
3.02 No evidence  
3.03 No evidence  
3.04 No evidence  
3.05 (1)Acmella uliginosa is reported to be invasive on Fiji Islands.  (2)Acmella sodiroi is reported to be invasive in Ecuador (Galapagos Islands).
4.01 No evidence
4.02 No evidence  
4.03 No evidence  
4.04 Don’t know.  
4.05 No evidence  
4.06 No evidence regarding associated pests.  
4.07 No evidence  
4.08 Distribution and occurrence: Grows in swamps and wet areas, uncommon, north from Lismore district. [Probably not - occurs in wet areas, uncommon, not known to occur in groups, herbaceous plant].
4.09 No evidence regarding light requirements of this species.  
4.1 No evidence regarding the soil requirements of this species.  
4.11 Herb up to 60 cm high.
4.12 No evidence  
5.01 Herb up to 60 cm high.
6.01 Probably not - "Options B, C and D are unlikely to have a significant impact due to large and extensive regional population."
6.02 No evidence regarding reproduction in this species.  
6.03 Dont know - "Abstract: Chromosome counts are reported for 372 individuals from 202 populations in 26 taxa of Acmella (Asteraceae: Heliantheae). Chromosome numbers for 15 taxa [A. ciliata, A. papposa var. papposa, A. pilosa, A. pusilla, A. brachyglossa, A. iodiscaea, A. radicans var. debilis, A. paniculata, A. alpestris, A. bellidioides, A. glaberrima, A. grandiflora, A. grisea, A. leptophylla and A. serratifolia] are first reports. A review of previous counts and the new reports supports a basic chromosome number of 13 for the genus. The results show that polyploidy, sometimes accompanied by hybridization and asexual reproduction, is widespread in Acmella and has contributed to the taxonomic difficulties in the genus. These factors have produced a variable polyploid pillar complex in sect. Acmella. In one taxon in this complex, A. oppositifolia var. oppositifolia, intrataxon and even intrapopulational chromosomal variation has been detected. Morphological studies in conjunction with observations of meiotic pairing suggest that most polyploids are alloploid in origin. The occurrence of polyploidy in 16 of the 27 taxa known chromosomally emphasizes the important role this process has had in speciation within Acmella. Although intrataxon chromosomal variation has limited the taxonomic utility of chromosome numbers, a few examples are presented in which these data have been valuable for separating some pairs of closely related taxa (A. decumbens var. affinis from var. decumbens and A. poliolepidica from A. oppositifolia)." JANSEN R K SYSTEMATIC SIGNIFICANCE OF CHROMOSOME NUMBERS IN ACMELLA ASTERACEAE
American Journal of Botany 72 (12) : 1835-1841 1985
6.04 No evidence regarding reproduction in this species.  
6.05 Probably not - see photo - a typical daisy like flower in the Asteraceae.
6.06 Dotn know - no evidence regarding the reproduction in this species.  
6.07 An herbaceaous species - probably 1 to 2 years.  
7.01 Probably not - not known to occur or to be grown in heavily trafficked areas.  
7.02 Probably yes - flowers appear to be attractive - but no evidence of it being sold or propagated for ornamental purposes.l  
7.03 No evidence that the species occurs or is grown around seed crops.  
7.04 Probably yes ' "Achenes 1.5--2.5 mm long; margins ciliate; pappus absent or often 2 or 3 subequal bristles. "
7.05 No evidence.  
7.06 No evidence  
7.07 "Achenes 1.5--2.5 mm long; margins ciliate; pappus absent or often 2 or 3 subequal bristles. " [No evidence that the speceis can disperse via attachment of seeds, however the description of the achenes - 'bristles' suggests that it might be able to disperse vai attachement too].
7.08 No evidence  
8.01 Achenes 1.5--2.5 mm long; margins ciliate; pappus absent or often 2 or 3 subequal bristles.
8.02 No evidence regarding longevity of seeds.  
8.03 No evidence that the species is being controlled for.  
8.04 Don’t know.  
8.05 Don’t know.  

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This page created 23 December 2006