Pacific Island Ecosystems at Risk (PIER)
RISK ASSESSMENT RESULTS: High risk, score: 26
|
Australian/New Zealand Weed Risk Assessment adapted for Hawai‘i. Information on Risk Assessments Original risk assessment |
| Cortaderia jubata (Common name: Andean pampas grass, jubata grass, pink pampas grass, purple pampas grass) Family - Poaceae Synonym: Gynerium jubatum | 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) | ||
| 3.03 | Agricultural/forestry/horticultural weed y = 2*multiplier (see Append 2) | y | 4 |
| 3.04 | Environmental weed y = 2*multiplier (see Append 2) | y | 4 |
| 3.05 | Congeneric weed y = 1*multiplier (see Append 2) | y | 2 |
| 4.01 | Produces spines, thorns or burrs | y | 1 |
| 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 | y | 1 |
| 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 | y | 1 |
| 5.01 | Aquatic | n | 0 |
| 5.02 | Grass | y | 1 |
| 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 | y | 1 |
| 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) | y | 1 |
| 7.02 | Propagules dispersed intentionally by people | y | 1 |
| 7.03 | Propagules likely to disperse as a produce contaminant | y | 1 |
| 7.04 | Propagules adapted to wind dispersal | y | 1 |
| 7.05 | Propagules water dispersed | y | 1 |
| 7.06 | Propagules bird dispersed | n | -1 |
| 7.07 | Propagules dispersed by other animals (externally) | y | 1 |
| 7.08 | Propagules survive passage through the gut | n | -1 |
| 8.01 | Prolific seed production (>1000/m2) | y | 1 |
| 8.02 | Evidence that a persistent propagule bank is formed (>1 yr) | n | -1 |
| 8.03 | Well controlled by herbicides | y | -1 |
| 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: | 26 | ||
Supporting data:
| Notes | Reference | |
| 1.01 | No evidence | |
| 1.02 | (1)"In Hawai‘i naturalized in dry to wet zones, from 2000 ft to 7,000 ft. Forms dense monotypic stands in mesic to humid areas with the potential to replace or compete with native species." "A problem species in New Zealand (declared noxious weed). On Hawai‘i noxious weed list." (2)"It is an aggressive colonizer that competes with native vegetation. It can displace native coastal dune, shrub, and estuarine vegetation, and it slows early forest re-growth on logged lands. ... Andean Pampas/Jubata grass is a threat to the integrity of coastal dune, shrub and estuarine ecosystems." (3)"Jubatagrass is one of the most invasive nonnative species along sensitive natural coastal sites of California." | (1)http://www.hear.org/pier/species/cortaderia_jubata.htm (2)http://www.nps.gov/archive/redw/pampas.htm (3)Drewitz, Jennifer J.; DiTomaso, Joseph M. Seed biology of jubatagrass (Cortaderia jubata) Weed Science 52 (4) : 525-530 July 2004 |
| 1.03 | No evidence | |
| 2.01 | (1)"Native range: South America." (2)"Cortaderia is native to the Andes Mountains of northern Argen¬tina, Bolivia, Peru, and Ecuador at elevations of 2800 to 3400 m (Costas Lippmann 1977, 1979), where it can form nearly solid stands of several hundred hectares." | (1)http://www.hear.org/pier/species/cortaderia_jubata.htm (2)http://tncweeds.ucdavis.edu/esadocs/documnts/cortjub.rtf |
| 2.02 | ||
| 2.03 |
(1)"However, it has broad habitat requirements and will grow vigorously in
nearly any soil, under low or high moisture regimes, in full sun or dense
shade." (2)"It has broad habitat requirements and grows vigorously … '
(3)Hardiness: USDA Zone 5a: to -28.8° C (-20° F) USDA Zone 5b: to -26.1° C (-15° F) USDA Zone 6a: to -23.3° C (-10° F) USDA Zone 6b: to -20.5° C (-5° F) USDA Zone 7a: to -17.7° C (0° F) USDA Zone 7b: to -14.9° C (5° F) USDA Zone 8a: to -12.2° C (10° F) USDA Zone 8b: to -9.4° C (15° F) USDA Zone 9a: to -6.6° C (20° F) USDA Zone 9b: to -3.8° C (25° F) |
(1)http://tncweeds.ucdavis.edu/esadocs/documnts/cortjub.rtf (2)http://www.issg.org/database/species/ecology.asp?si=375&fr=1&sts= (3)http://davesgarden.com/pf/go/31957/index.html |
| 2.04 | (1)"Native range: South America." (2)"Cortaderia is native to the Andes Mountains of northern Argen¬tina, Bolivia, Peru, and Ecuador at elevations of 2800 to 3400 m (Costas Lippmann 1977, 1979), where it can form nearly solid stands of several hundred hectares." | (1)http://www.hear.org/pier/species/cortaderia_jubata.htm (2)http://tncweeds.ucdavis.edu/esadocs/documnts/cortjub.rtf |
| 2.05 | Known introduced range: C. jubata is now found in New Zealand, Australia, the United States, and South Africa | (1)http://www.hear.org/pier/species/cortaderia_jubata.htm (2)http://www.nps.gov/archive/redw/pampas.htm (3)Drewitz, Jennifer J.; DiTomaso, Joseph M. Seed biology of jubatagrass (Cortaderia jubata) Weed Science 52 (4) : 525-530 July 2004 (4)http://www.issg.org/database/species/ecology.asp?si=375&fr=1&sts= |
| 3.01 | (1)"In Hawai‘i naturalized in dry to wet zones, from 2000 ft to 7,000 ft. Forms dense monotypic stands in mesic to humid areas with the potential to replace or compete with native species." "A problem species in New Zealand (declared noxious weed). On Hawai‘i noxious weed list." (2)"It is an aggressive colonizer that competes with native vegetation. It can displace native coastal dune, shrub, and estuarine vegetation, and it slows early forest re-growth on logged lands. ... Andean Pampas/Jubata grass is a threat to the integrity of coastal dune, shrub and estuarine ecosystems." (3)"Jubatagrass is one of the most invasive nonnative species along sensitive natural coastal sites of California." | (1)http://www.hear.org/pier/species/cortaderia_jubata.htm (2)http://www.nps.gov/archive/redw/pampas.htm (3)Drewitz, Jennifer J.; DiTomaso, Joseph M. Seed biology of jubatagrass (Cortaderia jubata) Weed Science 52 (4) : 525-530 July 2004 |
| 3.02 | (1)Habitat/ecology: Disturbed areas, clearings, sand dunes, roadsides, grasslands, pastures, alpine shrublands. Invades disturbed areas, smothering other plants and preventing regeneration. (2)"PPC (1998) cites that on roadsides, C. jubata can seriously hamper visibility, while its sharp leaves can cause serious cuts to humans." | (1)http://www.hear.org/pier/species/cortaderia_jubata.htm (2)http://www.issg.org/database/species/ecology.asp?si=375&fr=1&sts= |
| 3.03 | "Habitat/ecology: Disturbed areas, clearings, sand dunes, roadsides, grasslands, pastures, alpine shrublands. Invades disturbed areas, smothering other plants and preventing regeneration." | http://www.hear.org/pier/species/cortaderia_jubata.htm |
| 3.04 | (1)"In Hawai‘i naturalized in dry to wet zones, from 2000 ft to 7,000 ft. Forms dense monotypic stands in mesic to humid areas with the potential to replace or compete with native species." "A problem species in New Zealand (declared noxious weed). On Hawai‘i noxious weed list." (2)"It is an aggressive colonizer that competes with native vegetation. It can displace native coastal dune, shrub, and estuarine vegetation, and it slows early forest re-growth on logged lands. ... Andean Pampas/Jubata grass is a threat to the integrity of coastal dune, shrub and estuarine ecosystems." (3)"Jubatagrass is one of the most invasive nonnative species along sensitive natural coastal sites of California." (4)It is on the 'State Noxious weed list' of 46 states in the U.S. | (1)http://www.hear.org/pier/species/cortaderia_jubata.htm (2)http://www.nps.gov/archive/redw/pampas.htm (3)Drewitz, Jennifer J.; DiTomaso, Joseph M. Seed biology of jubatagrass (Cortaderia jubata) Weed Science 52 (4) : 525-530 July 2004 (4)http://plants.usda.gov/java/profile?symbol=COJU2 |
| 3.05 |
"General impacts C. selloana can form dense stands that exclude other plants. Its sharp leaves cut skin and can limit recreational use of areas, and it can form dense colonies that can become or increase fire hazards (May et al., UNDATED). Once seedlings become established, it is a substantial threat to the ecological quality of preserves, particularly in coastal and grassland sites due to competition with native plants. Its rapid growth and accumulation of above ground and below ground biomass allow it to acquire light, moisture, and nutrients that would be used by other plants. It can be damaging even at low densities because of the amount of cover it can occupy (Starr et al. 2003). Studies comparing C. selloana with Cortaderia jubata a similar species found that C. selloana is genetically more diverse and could be one of the reasons of its success (Lambrinos, 2001).These results are consistent with the hypothesis that genetic variability enables better utilization of heterogeneous habitats as well as promoting greater competitive abilities. In California, C. selloana inhabits a greater range of environmental conditions expanding into continental climatic zones. The rapid spread of pampas into exotic forests in New Zealand is a particular problem due to it's competition with pine, fire hazard, reduced accessibility and cost of control (Gadgil et al., 1984). Also the great quantity of fluffy seed has caused problems for kiwifruit growers since it clings to the fruit and causes it to be rejected for exprot (Knowles and Tombleson, 1987)." |
http://www.invasivespecies.net/database/species/ecology.asp?si=373&fr=1&sts=sss |
| 4.01 | "Plant has spines or sharp edges; use extreme caution when handling." | http://davesgarden.com/pf/go/31957/index.html |
| 4.02 | No evidence | |
| 4.03 | No evidence | |
| 4.04 | "It has also been used as a forage plant for cattle in California and New Zealand. " | http://tncweeds.ucdavis.edu/esadocs/documnts/cortjub.rtf |
| 4.05 | No evidence | |
| 4.06 |
The following six fungi species were listed ot be associated with C. jubata:
Exserticlava vasiformis: New Zealand - 7073 Nigrospora sacchari: New Zealand - 7073 Sporoschisma nigroseptatum: New Zealand - 8554 Fusarium equiseti: New Zealand - 40040 Gibberella intricans: New Zealand - 6224 Gibberella zeae: New Zealand - 6224 [No evidence that the above are economic pests]. |
|
| 4.07 | No evidence | |