Pacific Island Ecosystems at Risk (PIER)


Archontophoenix alexandrae


RISK ASSESSMENT RESULTS: High risk, score: 8 (revised 22 January 2008)


Australian/New Zealand Weed Risk Assessment adapted for Hawai‘i.

Research directed by C. Daehler (UH Botany) with funding from the Kaulunani Urban Forestry Program and US Forest Service

Information on Risk Assessments
Original risk assessment

Archontophoenix alexandrae (F. Muell.) H. Wendl. Family - Arecaceae. Common Names - Alexandra palm, king palm. Synonyms - Ptychosperma alexandrae.

Answer

Score

1.01

Is the species highly domesticated?

y=-3, n=0

n

0

1.02

Has the species become naturalized where grown?

y=-1, n=-1

1.03

Does the species have weedy races?

y=-1, n=-1

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”

See Append 2

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, n=0

n

0

2.04

Native or naturalized in regions with tropical or subtropical climates

y=1, n=0

y

1

2.05

Does the species have a history of repeated introductions outside its natural range? y=-2

?=-1, n=0

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

0

0

3.03

Agricultural/forestry/horticultural weed y = 2*multiplier (see Append 2)

n=0

0

0

3.04

Environmental weed y = 2*multiplier (see Append 2)

n=0

0

0

3.05

Congeneric weed y = 1*multiplier (see Append 2)

n=0

y

2

4.01

Produces spines, thorns or burrs

y=1, n=0

n

0

4.02

Allelopathic

y=1, n=0

n

0

4.03

Parasitic

y=1, n=0

n

0

4.04

Unpalatable to grazing animals

y=1, n=-1

4.05

Toxic to animals

y=1, n=0

n

0

4.06

Host for recognized pests and pathogens

y=1, n=0

y

1

4.07

Causes allergies or is otherwise toxic to humans

y=1, n=0

n

0

4.08

Creates a fire hazard in natural ecosystems

y=1, n=0

n

0

4.09

Is a shade tolerant plant at some stage of its life cycle

y=1, n=0

y

1

4.1

Tolerates a wide range of soil conditions (or limestone conditions if not a volcanic island)

y=1, n=0

n

0

4.11

Climbing or smothering growth habit

y=1, n=0

n

0

4.12

Forms dense thickets

y=1, n=0

y

1

5.01

Aquatic

y=5, n=0

n

0

5.02

Grass

y=1, n=0

n

0

5.03

Nitrogen fixing woody plant

y=1, n=0

n

0

5.04

Geophyte (herbaceous with underground storage organs -- bulbs, corms, or tubers)

y=1, n=0

n

0

6.01

Evidence of substantial reproductive failure in native habitat

y=1, n=0

n

0

6.02

Produces viable seed.

y=1, n=-1

y

1

6.03

Hybridizes naturally

y=1, n=-1

y

1

6.04

Self-compatible or apomictic

y=1, n=-1

y

1

6.05

Requires specialist pollinators

y=-1, n=0

n

0

6.06

Reproduction by vegetative fragmentation

y=1, n=-1

n

-1

6.07

Minimum generative time (years) 1 year = 1, 2 or 3 years = 0, 4+ years = -1

See left

4

-1

7.01

Propagules likely to be dispersed unintentionally (plants growing in heavily trafficked areas)

y=1, n=-1

n

-1

7.02

Propagules dispersed intentionally by people

y=1, n=-1

y

1

7.03

Propagules likely to disperse as a produce contaminant

y=1, n=-1

n

-1

7.04

Propagules adapted to wind dispersal

y=1, n=-1

n

-1

7.05

Propagules water dispersed

y=1, n=-1

y

1

7.06

Propagules bird dispersed

y=1, n=-1

y

1

7.07

Propagules dispersed by other animals (externally)

y=1, n=-1

n

-1

7.08

Propagules survive passage through the gut

y=1, n=-1

y

1

8.01

Prolific seed production (>1000/m2)

y=1, n=-1

y

1

8.02

Evidence that a persistent propagule bank is formed (>1 yr)

y=1, n=-1

n

-1

8.03

Well controlled by herbicides

y=-1, n=1

8.04

Tolerates, or benefits from, mutilation, cultivation, or fire

y=1, n=-1

n

-1

8.05

Effective natural enemies present locally (e.g. introduced biocontrol agents)

y=-1, n=1

Total score:

8

Supporting data:

Source

Notes

1.01

no evidence

1.02

http://www.hear.org/starr/hiplants/reports/html/archontophoenix_alexandrae.htm

"In Hawai'i, A. alexandrae is escaping from plantings and is naturalized in low elevation mesic to wet valleys, especially on the island of Hawai'i from Hilo to the Hamakua coast area (Wagner et al. 1999). In this area, A. alexandrae was densely planted along the road and has readily naturalized in adjacent areas along roadsides, gulches, and stream beds where it competes aggressively with other disturbed wet weeds in the area"

1.03

no evidence

2.01

USDA, ARS, National Genetic Resources Program. Germplasm Resources Information Network - (GRIN). [Online Database] National Germplasm Resources Laboratory, Beltsville, Maryland. Available: http://www.ars-grin.gov/cgi-bin/npgs/html/taxon.pl?3853 (26 July 2003)

Native distributional range: Australasia: Australia - Queensland [n.]

2.02

2.03

(1)http://www.hear.org/starr/hiplants/reports/html/archontophoenix_alexandrae.htm (2)http://www.pacsoa.org.au/palms/Archontophoenix/overview.html (3)http://www.forests.qld.gov.au/qts/treetext.html

(1) "A. alexandrae is a stately garden palm widely grown in tropical and subtropical countries"; "Young Archontophoenix trees will not tolerate frost, but adult plants may stand 28 F (-2 C)"; "Native range: A. alexandrae are native to coastal rainforests of north Queensland, eastern Australia, where it is distributed between Gladstone and the Melville Range near Bathurst Bay on the Cape York Peninsula (Jones 1995, Turner and Wasson 1997). A. alexandrae commonly grows in lowland swamp forests, but is also found up to 600 m (1,968 ft) elevation in the ranges (Jones 1995). Average annual rainfall in this part of Australia ranges from 60 to over 80 in (150 to over 200 cm) and average temperature ranges from over 68 F (20-30 C) in July to over 86 F (over 30 C) in January (Hammond 1986)." (2) Main habitats include rainforest, wet sclerophyll, gallery forest, moist vineforest and swampforest (3)Occurs naturally in coastal areas from Bundaberg to Cape York.

2.04

USDA, ARS, National Genetic Resources Program. Germplasm Resources Information Network - (GRIN). [Online Database] National Germplasm Resources Laboratory, Beltsville, Maryland. Available: http://www.ars-grin.gov/cgi-bin/npgs/html/taxon.pl?3853 (26 July 2003)

Native distributional range: Australasia: Australia - Queensland [n.]

2.05

(1)http://www.hear.org/starr/hiplants/reports/html/archontophoenix_alexandrae.htm (2)http://www.islapro.com/ecologia/generes/archontophoenix.html

(1)"A. alexandrae palms are widely cultivated as ornamentals in tropical and subtropical countries of the world " (2)grown outdoors in southern Florida and in southern California

3.01

(1)http://www.hear.org/starr/hiplants/reports/html/archontophoenix_alexandrae.htm (2)Wunderlin. 1998. Guide to the vascular plants of Florida

(1)"In Hawai'i, A. alexandrae is escaping from plantings and is naturalized in low elevation mesic to wet valleys, especially on the island of Hawai'i from Hilo to the Hamakua coast area (Wagner et al. 1999). In this area, A. alexandrae was densely planted along the road and has readily naturalized in adjacent areas along roadsides, gulches, and stream beds where it competes aggressively with other disturbed wet weeds in the area" (2)NOT naturalized in Florida [although widely planted]

3.02

no evidence

3.03

no evidence

3.04

http://www.hear.org/starr/hiplants/reports/html/archontophoenix_alexandrae.htm

MANAGEMENT RECOMMENDATIONS
The A. alexandrae infestation on the island of Hawai'i is quite impressive. In this preferred wet disturbed lowland climate, A. alexandrae, with prolific seed production, is aggressively filling gulches and lining streams and roadsides in dense tall thickets. On Maui, this species is widely cultivated and sparingly naturalized in a few moist to wet habitats. If feasible, these sites could be controlled before they become major infestations. The potential for this palm to infest large areas of lowland wet forests of Maui currently free of A. alexandrae seems high. The public could be informed of the invasive nature of this palm and asked not to plant them in moist habitats. The distribution on Maui should be periodically updated and monitored. [suggestions to control its naturalized populations, but no control efforts to date and no documentation of native habitats, only disturbed lowland habitats; no threats to native species reported]

3.05

(1) Data obtained from this and other studies pointed out to a massive increase in seed production of A. cunninghamiana in a few years within the fragment. I suggest that this invasive palm can be taking advantage of the absence of Euterpe edulis Mart., a native palm which has similar biology, and was locally extinct due to human disturbances. Recommendations to control the invasion include the continuous removal of all Archontophoenix larger than 15 cm DBH, and the establishment of a buffer zone free of Archontophoenix around the fragment to decrease propagule pressure. (2) This work reports the invasion of the Reserve of the Cidade Universitária “Armando de Salles Oliveira” (23o34’ S, 46o43’ W), a small (10 ha) forest fragment, by a palm native of Australia...The high density already achieved by the invader and its tendency to increase even more call for management actions in order to reverse the invasion process.

(1) Christianini, A. V. 2006. Fecundity, dispersal and predation of seeds of Archontophoenix cunninghamiana H. Wendl.& Drude, an invasive palm in the Atlantic forest. Rev. bras. Bot. 29(4): p.587-594.

4.01

http://www.hear.org/starr/hiplants/reports/html/archontophoenix_alexandrae.htm

no description of these traits

4.02

no evidence

4.03

no evidence

4.04

no evidence [most palm leaves are rich in fiber, and will be out of the reach of grazing animals once grown tall but seedlings are possibly palatable]

4.05

no evidence

4.06

Supriadi; Mulya, K.; Sitepu, D. (2001) Bacterial wilt disease of woody trees caused by Ralstonia solanacearum : a review. Jurnal Penelitian dan Pengembangan Pertanian, 2001, Vol.20, No.3, pp.106-112, 40 ref.
(2) Lau, C. S. K. (1991) Occurrence of Brontispa longissima Gestro in Hong Kong. Quarterly Newsletter - Asia and Pacific Plant Protection Commission, 1991, Vol.34, No.3-4, p.10

AB: "Ralstonia (syn. Pseudomonas ) solanacearum is an important pathogenic bacterium causing serious wilt disease on many plants, including several economically important woody trees. Fourteen species of woody plants reported as hosts of the pathogen are Alexandra palm (Archontophoenix alexandrae ), cashew (Anacardium occidentale ), clove (Syzygium aromaticum ), custard apple (Annona squamosa and Annona cherimola ), eucalyptus (Eucalyptus spp.), mulberry (Morus alba ), neem (Azadirachta indica ), nutmeg (Myristica fragrans ), olive (Olea europaea ), teak (Tectona grandis ), wax apple (Eugenia javanica ), and other trees locally known as "petai cina" (Leucaena glauca [Leucaena leucocephala ]), "kelor" (Moringa oleifera ) and "ki pahang" (Pongamia pinnata ). "
[broad host ranges]
(2) AB: In a survey in Hong Kong, Brontispa longissima was found to infest Washingtonia robusta, Archontophoenix alexandrae and Phoenix roebelenii as well as its previously known hosts. [a beetle that attacks coconut]

4.07

no evidence

4.08

http://members.cts.com/king/v/ventana/kingpalm.htm

Low flammability

4.09

(1)http://www.hear.org/starr/hiplants/reports/html/archontophoenix_alexandrae.htm (2)http://www.encephalartos.com/palms/archontophoenix-alexandrae.htm (3)http://www.plantapalm.com/Vpe/photos/Species/archontophoenix_alexandrae.htm (4)http://www.forests.qld.gov.au/qts/treetext.html (5)http://miami-dade.ifas.ufl.edu/programs/commorn/publications/growing-shady-plants.PDF

(1)"A. alexandrae grows best in partial shade when young and full sun once the crown reaches full height" (2)Partial or full sun. (3)It needs bright light (4)Requires some shade when young. (5)Suitable for shady places

4.1

(1)http://www.hear.org/starr/hiplants/reports/html/archontophoenix_alexandrae.htm
(2) http://www.plantapalm.com/vpe/photos/Species/archontophoenix_alexandrae.htm (3)http://www.thegreenescape.com/Merchant2/merchant.mv?
Screen=PROD&Store_Code=any&Product_Code=Archontophoenix_alexandrae-King_Palm (4)http://www.encephalartos.com/palms/archontophoenix-alexandrae.htm (5)http://www.plantapalm.com/Vpe/photos/Species/archontophoenix_alexandrae.htm (6)http://www.rainbowtropicals.com/KingAlexandra.html

(1) "tolerate both boggy conditions and dry spells, but prefer moist, fertile soil"

(2) "It needs bright light, rich and moist soil" (3)Moist loamy soils (4)palm likes a quick draining and sandy top soil. (5)rich and moist soil (6)prefers loose sandy soil.

4.11

a tall palm with single stem

4.12

(1)http://www.hear.org/starr/hiplants/reports/html/archontophoenix_alexandrae.htm (2)http://www.pacsoa.org.au/palms/Archontophoenix/overview.html

(1)" A. alexandrae occurs from Hilo to the Hamakua coast on the island of Hawai'i, spreading away from initial plantings in dense, tall thickets along the road, in gulches, and lining streams. " (2)Lowland and moderate altitude populations are continuous for many kilometres where conditions permit [in native habitat]

5.01

terrestrial

5.02

palm; Arecaceae

5.03

no evidence

5.04

palm

6.01

no evidence

6.02

Martins, C. C.; Bovi, M. L. A.; Nakagawa, J. (2003) Desiccation effects on germination and vigor of King palm seeds. Horticultura Brasileira, 2003, Vol.21, No.1, pp.88-92, 21 ref.

AB: "The seeds of A. alexandrae are recalcitrant, with high germination percentage (>67%) when undried (47% seed moisture). "

6.03

http://www.hear.org/starr/hiplants/reports/html/archontophoenix_alexandrae.htm

Members of this genus readily hybridize with each-other (Jones, D. L. 1995. Palms Throughout the World. Smithsonian Institution Press, Washington, DC.)

Hamilton Main Reference-Library Use Only; Call Number: SB317 .P3 J66 1995

6.04

http://www.hear.org/starr/hiplants/reports/html/archontophoenix_alexandrae.htm

"Pollination: Single plants are capable of producing fertile seeds"

6.05

http://www.forests.qld.gov.au/qts/treetext.html

Flowers are creamy white / mauve [typical Arecaeae flowers, visited by bees]

6.06

no evidence

6.07

http://www.pacsoa.org.au/palms/Archontophoenix/alexandrae.html

It is quite a fast grower, averaging about 1/3 - 1 metre (1-3 feet) per year. [flowering specimens are usually at least 12 ft high]

7.01

[although grown in high trafficed areas, the fruits may be too large to be dispersed unintentionally]

7.02

http://www.hear.org/starr/hiplants/reports/html/archontophoenix_alexandrae.htm

"A. alexandrae is a stately garden palm widely grown in tropical and subtropical countries and valued for their graceful ornamental appearance"

7.03

no evidence

7.04

http://www.hear.org/starr/hiplants/reports/html/archontophoenix_alexandrae.htm

"Fruit red, 1-1.4 cm long, 0.8-1.1 cm in diameter"

7.05

http://www.hear.org/starr/hiplants/reports/html/archontophoenix_alexandrae.htm

"Dispersal: This palm, with relatively small fruit, could presumably be dispersed by birds, water, pigs, and humans"; "A. alexandrae occurs from Hilo to the Hamakua coast on the island of Hawai'i, spreading away from initial plantings in dense, tall thickets along the road, in gulches, and lining streams."

7.06

http://www.hear.org/starr/hiplants/reports/html/archontophoenix_alexandrae.htm

"Dispersal: This palm, with relatively small fruit, could presumably be dispersed by birds, water, pigs, and humans"

7.07

no evidence

7.08

bird-dispersed

8.01

http://www.hear.org/starr/hiplants/reports/html/archontophoenix_alexandrae.htm

"Fruit red, 1-1.4 cm long, 0.8-1.1 cm in diameter" [small fruit for a palm, picture shows a single inflorescens may contain hundreds to thousands of seeds]

8.02

Martins, C. C.; Bovi, M. L. A.; Nakagawa, J. (2003) Desiccation effects on germination and vigor of King palm seeds. Horticultura Brasileira, 2003, Vol.21, No.1, pp.88-92, 21 ref.

AB: "The seeds of A. alexandrae are recalcitrant, with high germination percentage (>67%) when undried (47% seed moisture). Lowering seed moisture below 31.5% reduced the germination rate significantly (<52.5%). Total germination failure was observed when seed moisture reached 15.1%. " [recalcitrant seed that do not withstand low humidity]

8.03

http://www.hear.org/starr/hiplants/reports/html/archontophoenix_alexandrae.htm

Chemical control: Unknown. It may be possible to control with basal bark applications of herbicide.

8.04

http://www.hear.org/starr/hiplants/reports/html/archontophoenix_alexandrae.htm

"Physical control: Unwanted young palms could probably be pulled up by hand, or dug out with picks and shovels. Larger trees could be killed by cutting the top off below the crownshaft, or digging up the root ball."

8.05

Don't Know


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