Pacific Island Ecosystems at Risk (PIER)


Eucalyptus dunnii


RISK ASSESSMENT RESULTS: Low risk, score: 0


Australian/New Zealand Weed Risk Assessment adapted for Hawai‘i.
Information on Risk Assessments
Original risk assessment
  Eucalyptus dunnii (Dunn's white gum) Answer Score
1.01 Is the species highly domesticated? n 0
1.02 Has the species become naturalized where grown? n  
1.03 Does the species have weedy races? n  
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) y 1
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 n 0
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) y 1
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. y 1
6.03 Hybridizes naturally y 1
6.04 Self-compatible or apomictic y 1
6.05 Requires specialist pollinators n 0
6.06 Reproduction by vegetative fragmentation n -1
6.07 Minimum generative time (years)                 1 year = 1, 2 or 3 years = 0, 4+ years = -1 4 -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 n -1
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) n -1
7.08 Propagules survive passage through the gut n -1
8.01 Prolific seed production (>1000/m2) n -1
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 y 1
8.05 Effective natural enemies present locally (e.g. introduced biocontrol agents)    
  Total score:   0

Supporting data:

  Notes Reference
1.01 No evidence  
1.02 No evidence of naturalization.  
1.03 No evidence  
2.01  '. dunnii has a very restricted natural distribution. It occurs mostly in two main small, disjunct, natural populations located in the Moleton-Kangaroo River area of New South Wales, north-west of Coffs Harbour (30ºS), and in the Border Ranges of New South Wales and Queensland (about 28ºS). Within these two populations, the species' distribution is not continuous; it occurs in disjunct communities varying in size from several up to more than 200 ha (Benson and Hager, 1993). Several isolated small stands occur just south of the Border Ranges in the Richmond Range area of New South Wales.' Reproduced from the Forestry Compendium. © CAB International, Wallingford, UK, 2005.
2.02 It has been included in trials in many countries including South Africa, Zimbabwe, Kenya, Colombia, Brazil, Uruguay, Argentina, Chile, China and Sri Lanka.' Reproduced from the Forestry Compendium. © CAB International, Wallingford, UK, 2005.
2.03 (1) In its natural environment, E. dunnii is found in areas with an altitudinal range from 300 – 750 m and experiences relatively high rainfall and with no month receiving less than 40 mm1.(2)- Altitude range: 60 - 1800 m
- Mean annual rainfall: 750 - 1950 mm
- Rainfall regime: summer; uniform
- Dry season duration: 0 - 5 months
- Mean annual temperature: 14 - 22ºC
- Mean maximum temperature of hottest month: 24 - 31ºC
- Mean minimum temperature of coldest month: -1 - 17ºC
- Absolute minimum temperature: -9 - -2ºC
(1)http://www2.dpi.qld.gov.au/hardwoodsqld/12610.html (2)Reproduced from the Forestry Compendium. © CAB International, Wallingford, UK, 2005.
2.04  '. dunnii has a very restricted natural distribution. It occurs mostly in two main small, disjunct, natural populations located in the Moleton-Kangaroo River area of New South Wales, north-west of Coffs Harbour (30ºS), and in the Border Ranges of New South Wales and Queensland (about 28ºS). Within these two populations, the species' distribution is not continuous; it occurs in disjunct communities varying in size from several up to more than 200 ha (Benson and Hager, 1993). Several isolated small stands occur just south of the Border Ranges in the Richmond Range area of New South Wales.' Reproduced from the Forestry Compendium. © CAB International, Wallingford, UK, 2005.
2.05 It has been included in trials in many countries including South Africa, Zimbabwe, Kenya, Colombia, Brazil, Uruguay, Argentina, Chile, China and Sri Lanka.' Reproduced from the Forestry Compendium. © CAB International, Wallingford, UK, 2005.
3.01 No evidence of naturalization.  
3.02 No evidence  
3.03 No evidence  
3.04 No evidence  
3.05 Severa Eucalyptus species such as E. populnea,E.  pilularis, E. ferruginear and E. cambageana are listed as principal weeds in Australia.  An electronic Atlas of Weeds and Invasive Species. CD ROM version 1. 1997. Based on the original work 'A Geographical Atlas of Weeds' by Holm et al.
4.01 No evidence of any such traits. Forestry Compendium [Online]. © CAB International, Wallingford, UK, 2005.
4.02 No evidence  
4.03 No evidence  
4.04 Don’t know  
4.05 No evidence  
4.06  'Recorded pests:  Anoplognathus insect 
Cardiaspina maniformis insect 
Chrysophtharta insect 
Gonipterus gibberus (snout beetle, eucalyptus) insect 
Gonipterus scutellatus (eucalyptus snout beetle) insect 
Mnesampela privata insect 
Paropsis atomaria (Eucalyptus tortoise beetle) insect 
Phoracantha recurva (eucalyptus longhorned borer) insect 
Phylacteophaga froggatti (leafblister sawfly) insect 
Psyllidae (jumping plantlice) insect
[No evidence that the above are economic pests].
Reproduced from the Forestry Compendium. © CAB International, Wallingford, UK, 2005.
4.07  No evidence  
4.08 In its natural environment, E. dunnii is found in areas with an altitudinal range from 300 – 750 m and experiences relatively high rainfall and with no month receiving less than 40 mm1.(2)- Altitude range: 60 - 1800 m [Probably unlikely to be a fire hazard if it occurs in regions with relatively high rainfall].  
4.09    
4.1  'As an exotic, it has demonstrated adaptability to a wide range of soil types of good depth and moderate to high fertility. - Soil texture: medium
- Soil drainage: free
- Soil reaction: acid; neutral
- Soil types: alluvial soils; lateritic soils; volcanic soils
Reproduced from the Forestry Compendium. © CAB International, Wallingford, UK, 2005.
4.11 Not a climbing species. Forestry Compendium [Online]. © CAB International, Wallingford, UK, 2005.
4.12 No evidence.  
5.01  'A medium-sized to tall forest tree with a wide spreading and heavily branched crown in more open-grown situations. Mature heights of up to 50 m are attained with diameters at breast height up to 1-1.5 m. ' Reproduced from the Forestry Compendium. © CAB International, Wallingford, UK, 2005.
5.02  'A medium-sized to tall forest tree with a wide spreading and heavily branched crown in more open-grown situations. Mature heights of up to 50 m are attained with diameters at breast height up to 1-1.5 m. ' Reproduced from the Forestry Compendium. © CAB International, Wallingford, UK, 2005.
5.03 No evidence.  
5.04  'A medium-sized to tall forest tree with a wide spreading and heavily branched crown in more open-grown situations. Mature heights of up to 50 m are attained with diameters at breast height up to 1-1.5 m. ' Reproduced from the Forestry Compendium. © CAB International, Wallingford, UK, 2005.
6.01  'Flowering in its natural habitat is from March to May (i.e. autumn).' Reproduced from the Forestry Compendium. © CAB International, Wallingford, UK, 2005.
6.02  'E. dunnii is propagated from seed. Its seeds are small, orthodox and will remain viable in storage for several years if kept dry (5-8% moisture content) in air-tight containers held at room temperature.' Reproduced from the Forestry Compendium. © CAB International, Wallingford, UK, 2005.
6.03  'Interspecific hybrids of eucalypts are becoming increasingly important to forest industries worldwide and E. grandis is one of the most commonly used parent species in the combinations deployed. In southern Brazil, the hybrid of E. grandis x dunnii has provided some outstanding individuals (C. Harwood, CSIRO Forestry and Forestry Products, Canberra, pers. comm. 1997). Other combinations that have been successfully produced, at least to the seed stage, include E. dunnii x grandis, E. dunnii x urophylla, E. dunnii x macarthurii, E. nitens x dunnii, and E. macarthurii x dunnii (SAPPI, 1997). ' [The species is rare in its natural range. It appears that under forestry conditions, where E. dunnii is grown in proximation to other eucalyptus species it hybridizes, hence answered yes]. Reproduced from the Forestry Compendium. © CAB International, Wallingford, UK, 2005.
6.04  'The purpose of this work was to register the different stages and the duration of the reproductive cycle of E. dunnii, in Colombo, Parana, Brazil. Buds on two branches facing N., S., E. and W. were observed periodically. The reproductive cycle takes about 2 years to complete and the most interesting stage for pollen management (anthesis) is about 45 days. The results give evidence of flowering asynchrony among clones and it is suggested that supplementary mass pollination and control on early and late flowering should be done to avoid inbreeding.' [Probably yes - the abstract suggests the ability of the speceis to inbreed]. Flowering and fruit phenology of Eucalyptus dunnii . / Fenologia de florescimento e frutificacao de Eucalyptus dunnii By: Sousa, V. A. de;  Boletim de Pesquisa Florestal (22/23), 1991, p.9-19 (Journal article).
6.05 Probably not - floral morphology does not suggest any specialtist pollinator requirements. Reproduced from the Forestry Compendium. © CAB International, Wallingford, UK, 2005.
6.06 No evidence of vegetative spread.  
6.07  'Its use as an exotic in many countries has been severely limited by lack of seed - a consequence of its tendency to be a shy seeding species. It can take 10 years or more in many locations before E. dunnii will start to flower and produce seed. Even then, seed production tends to be relatively light and irregular. ...  However, when planted well south of its natural range in inland south-eastern Australia, an area with a Mediterranean climate, individuals have been observed to flower from as early as age 4 years.' Reproduced from the Forestry Compendium. © CAB International, Wallingford, UK, 2005.
7.01 Probably not - species grown for agroforestry purposes - no evidence that the propagules have any means ot attachemnt  and/or are stick).  
7.02  'It is cultivated for wood, used for - fuelwood; sawn or hewn building timbers; for light construction; carpentry/joinery; veneers; wood based materials; plywood; particleboard; pulp; short fibre pulp; charcoal. [Probably yes - a desirable forestry speceis.] Reproduced from the Forestry Compendium. © CAB International, Wallingford, UK, 2005.
7.03    
7.04 Probably yes - woody capsule with small seeds borne on tall trees. Reproduced from the Forestry Compendium. © CAB International, Wallingford, UK, 2005.
7.05 Probably not - no evidence that the species inhabits water ways in its natural habitat.  
7.06 Probably not - woody capsule with small seeds. Reproduced from the Forestry Compendium. © CAB International, Wallingford, UK, 2005.
7.07 Proabbably not - no evidence that the propagules have any means of attachment.  
7.08 Probably not - no evidence of ingestion by animals.  
8.01  'Its use as an exotic in many countries has been severely limited by lack of seed - a consequence of its tendency to be a shy seeding species. It can take 10 years or more in many locations before E. dunnii will start to flower and produce seed. Even then, seed production tends to be relatively light and irregular.' Reproduced from the Forestry Compendium. © CAB International, Wallingford, UK, 2005.
8.02  'E. dunnii is propagated from seed. Its seeds are small, orthodox and will remain viable in storage for several years if kept dry (5-8% moisture content) in air-tight containers held at room temperature.' [No evidence of seed viability under natural conditions]. Reproduced from the Forestry Compendium. © CAB International, Wallingford, UK, 2005.
8.03 No evidence that the species is being controlled for.  
8.04  'Eucalyptus dunnii is reported to coppice well.' Reproduced from the Forestry Compendium. © CAB International, Wallingford, UK, 2005.
8.05 Don’t know.  

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