Pacific Island Ecosystems at Risk (PIER)


Khaya nyasica


RISK ASSESSMENT RESULTS: Low risk, score: -1


Australian/New Zealand Weed Risk Assessment adapted for Hawai‘i.
Information on Risk Assessments
Original risk assessment
  Khaya nyasica (East African Mahogany)- Meliaceae Answer Score
1.01 Is the species highly domesticated? n 0
1.02 Has the species become naturalized where grown? y  
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 y 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) n 0
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 n -1
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 y 1
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    
6.04 Self-compatible or apomictic n -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 2 0
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) n -1
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:   -1

Supporting data:

   Notes Reference
1.01 No evidence  
1.02 Naturalized in Puerto Rico. http://www.fao.org/docrep/006/j1583e/J1583E10.htm
1.03 No evidence  
2.01 (1)Natural populaitions occur in Arica. (2)Khaya nyasica grows in central, eastern and southern Africa, including Malawi, Mozambique, South Africa, Tanzania, Zaire, Zambia and Zimbabwe.  (3)Origin - tropical Africa. (1)Forestry Compendium [Online]. © CAB International, Wallingford, UK, 2005.  (2)http://www.rngr.net/Publications/ttsm/Folder.2003-07-11.4726/PDF.2004-03-15.0458/file  (3)http://www.hear.org/gcw/html/autogend/species/10794.HTM
2.02 (1)Natural populaitions occur in Arica. (2)Khaya nyasica grows in central, eastern and southern Africa, including Malawi, Mozambique, South Africa, Tanzania, Zaire, Zambia and Zimbabwe.  (3)Origin - tropical Africa. (1)Forestry Compendium [Online]. © CAB International, Wallingford, UK, 2005.  (2)http://www.rngr.net/Publications/ttsm/Folder.2003-07-11.4726/PDF.2004-03-15.0458/file  (3)http://www.hear.org/gcw/html/autogend/species/10794.HTM
2.03  'The species grows from near sea level to 1400 m with the optimum elevation lying between 700 and 1000 m'. http://www.rngr.net/Publications/ttsm/Folder.2003-07-11.4726/PDF.2004-03-15.0458/file
2.04 (1)Natural populaitions occur in Arica. (2)Khaya nyasica grows in central, eastern and southern Africa, including Malawi, Mozambique, South Africa, Tanzania, Zaire, Zambia and Zimbabwe.  (3)Origin - tropical Africa. (1)Forestry Compendium [Online]. © CAB International, Wallingford, UK, 2005.  (2)http://www.rngr.net/Publications/ttsm/Folder.2003-07-11.4726/PDF.2004-03-15.0458/file  (3)http://www.hear.org/gcw/html/autogend/species/10794.HTM
2.05 Plantations of this species were tried in Cuba, Florida, Puerto Rico, and Nicaragua. http://www.fao.org/docrep/006/j1583e/J1583E10.htm
3.01 Naturalized in Puerto Rico. http://www.fao.org/docrep/006/j1583e/J1583E10.htm
3.02 No evidence  
3.03 No evidence  
3.04 No evidence  
3.05 No evidence  
4.01 No evidence of the presence of such structures.  
4.02 No evidence  
4.03 No evidence  
4.04 Browsing animals and rodents can destroy new production and set back development of sapling stands if not controlled.' http://www.worldagroforestry.org/sea/Products/AFDbases/af/asp/SpeciesInfo.asp?SpID=1026
4.05 No evidence  
4.06 It is resistant to termite att