Pacific Island Ecosystems at Risk (PIER)
Pandanus pygmaeus
RISK ASSESSMENT RESULTS: Low risk, score: 0
Australian/New Zealand Weed Risk Assessment adapted for Hawai‘i. Information on Risk Assessments Original risk assessment |
Pandanus pygmaeus (small screwpine) | Score | Answer | |
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) | n | 0 |
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 | n | |
3.01 | Naturalized beyond native range y = 1*multiplier (see Append 2), n= question 2.05 | n | 0 |
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 | y | 1 |
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 | y | 1 |
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. | y | 1 |
6.03 | Hybridizes naturally | ||
6.04 | Self-compatible or apomictic | n | -1 |
6.05 | Requires specialist pollinators | ||
6.06 | Reproduction by vegetative fragmentation | y | 1 |
6.07 | Minimum generative time (years) 1 year = 1, 2 or 3 years = 0, 4+ years = -1 | 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 | n | -1 |
7.05 | Propagules water dispersed | y | 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) | ||
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 | |
1.02 | No evidence | |
1.03 | No evidence | |
2.01 | (1)The herbarium specimens of P. Pgymaeus were all collected from Madagascar. (2)Paleotropic genus of probably 600-700 species. The greatest diversity in the genus is found in Madagascar (100 species) and Malesia (450-500 species). | (1)http://mobot.mobot.org/cgi-bin/search_vast (2)Wagner, W. L., Herbst, D. R., Sohmer, S. H. 1990. Manual of flowering plants of Hawaii. University of Hawaii Press. Honolulu. Hawaii. |
2.02 | ||
2.03 | Probably not - the altitudinal range of none of the specimens collected from Madagascar was greater than 800 m. | http://mobot.mobot.org/cgi-bin/search_vast |
2.04 | Paleotropic genus of probably 600-700 species. The greatest diversity in the genus is found in Madagascar (100 species) and Malesia (450-500 species). | Wagner, W. L., Herbst, D. R., Sohmer, S. H. 1990. Manual of flowering plants of Hawaii. University of Hawaii Press. Honolulu. Hawaii. |
2.05 | No evidence | |
3.01 | No evidence | |
3.02 | No evidence | |
3.03 | No evidence | |
3.04 | No evidence | |
3.05 | No evidence | |
4.01 | (1)Leaves green and spiny. (2)Thorny and hard green fruit. (3)Toothed leaf with spines at top | (1)http://mobot.mobot.org/cgi-bin/search_vast?ssdp=00922061 (2)http://mobot.mobot.org/cgi-bin/search_vast?ssdp=01202228 (3)http://mobot.mobot.org/cgi-bin/search_vast?ssdp=01225053 |
4.02 | No evidence | |
4.03 | No evidence | |
4.04 | Don’t know | |
4.05 | No evidence | |
4.06 | No evidence | |
4.07 | Edible fruits. | http://mobot.mobot.org/cgi-bin/search_vast?ssdp=00745887 |
4.08 | Probably not - an evergreen, low growing coastal species- grown in beaches, not know to form thickets. | |
4.09 | Requires full sun to partial shade. [No other evidence regarding ligh requirement. Unable to judge base on one reference]. |
http://www.nparks.gov.sg/nursery/ spe_by_search_details.asp?specode=6614&searchdetail=detail# |
4.1 | Suitable for seaside planting. [Suggests it can tolerate sandy soils and salt. No other evidence regarding soil requirement. Unable to judge base on one reference]. |
http://www.nparks.gov.sg/nursery/ spe_by_search_details.asp?specode=6614&searchdetail=detail# |
4.11 | No evidence | |
4.12 | No evidence | |
5.01 | Terrestrial (genus characteristic) | Wagner, W. L., Herbst, D. R., Sohmer, S. H. 1990. Manual of flowering plants of Hawaii. University of Hawaii Press. Honolulu. Hawaii. |
5.02 | (1)A shrub. (2)Treelet growing to 4 m high, with stilt roots. Lowest branches touching soil and rooting. Fruit unripe, green. |
(1)http://www.nparks.gov.sg/nursery/ spe_by_search_details.asp?specode=6614&searchdetail=detail# (2)http://mobot.mobot.org/cgi-bin/search_vast?ssdp=01385163 |
5.03 | No evidence | |
5.04 | Treelet growing to 4 m high, with stilt roots. Lowest branches touching soil and rooting. Fruit unripe, green. | http://mobot.mobot.org/cgi-bin/search_vast?ssdp=01385163 |
6.01 | Speciment notes from collections in Madagascar indicate the plants to be flowering and fruiting. | http://mobot.mobot.org/cgi-bin/search_vast |
6.02 | Probably yes - seeds sold commercially online. | http://www.equatorialexotics.com/price.htm |
6.03 | Don’t know | |
6.04 | (1)Pandanaceae are an ancient family of dioecious monocots dating from the early to mid-Cretaceous, and comprising three extant genera Sararanga, Freycinetia and Pandanus. (2)Genus characteristic - 'They are dioecious, with male and female flowers produced on different plants. The flowers of the male tree are 2-3 cm long and fragrant, surrounded by narrow, white bracts. The female tree produces flowers with round fruits that are also bract-surrounded.' |
(1)Callmander, Martin W.; Chassot, Philippe; Kupfer, Philippe, et al.
Recognition of Martellidendron, a new genus of Pandanaceae, and its
biogeographic implications. Taxon 52 (4) : 747-762 November 2003 (2)http://en.wikipedia.org/wiki/Pandanus |
6.05 | Don’t know - plant is dioeceous | |
6.06 | 'Treelet growing to 4 m high, with stilt roots. Lowest branches touching soil and rooting. Fruit unripe, green.' | http://mobot.mobot.org/cgi-bin/search_vast?ssdp=01385163 |
6.07 | ||
7.01 | No evidence that the species is grown in heavilty trafficked areas. | |
7.02 | (1)Grown for it ornamental foliage. (2)Plant available for purchase via internet. |
(1)http://www.nparks.gov.sg/nursery/ spe_by_search_details.asp?specode=6614&searchdetail=detail# (2)http://translate.google.com/translate?hl=en&sl=it&u=http:// www.topshare.de/c211.html&prev=/search%3Fq%3D Pandanus%2Bpygmaeus%26hl%3Den%26lr%3D%26sa%3DG |
7.03 | Probably not - no evidence that the species grows in or around seed crops. | |
7.04 | Probably not - not known in the genus. | |
7.05 |
Probably yes - (1)Grows on beaches. [Congener P. tectorius is distributed
from island to island by sea drifted fruits]. (2)Speciment (Missouri
Botanical Garden specimen id {00922061}, specimen id {00955847} ) was collected growing on the banks of the river Iantara in Madagascar. |
(1)Ref for P. tectoreius - Wagner et al. 1990. Manual of the flowering plants of Hawaii. University of Hawaii Press. Honolulu. Hawaii. Page -1480 (2)http://mobot.mobot.org/cgi-bin/search_vast?ssdp=00922061 |
7.06 | ||
7.07 | Based on the genus characteristics - no evidence that the propagules have any means of attachment. | Wagner et al. 1990. Manual of the flowering plants of Hawaii. University of Hawaii Press. Honolulu. Hawaii. Page -1480 |
7.08 | Probably not - in the congener P. tectorius crabs are known to disperse the seeds by carrying them and discarding the woody part that contains the seeds. | |
8.01 | Genus characteristic - The fruits are globose, 10 to 20 cm in diameter, and have many prism-like sections, resembling the fruit of the pineapple. [In P. tectorius the seeds are 8 - 15 mm long - Wagner et al. 1990. Manual of the flowering plants of Hawaii. University of Hawaii Press. Honolulu. Hawaii. Page -1480]. | http://en.wikipedia.org/wiki/Pandanus |
8.02 | No evidence regarding seed longevity. | |
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