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

Dictyosperma album (syn. D. alba, D. rubrum, Areca alba, Linoma alba); common princess palm, hurricane palm

Answer

1.01

Is the species highly domesticated?

y=-3, n=0

n

1.02

Has the species become naturalized where grown?

y=-1, n=-1

n

1.03

Does the species have weedy races?

y=-1, n=-1

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”

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

2.04

Native or naturalized in regions with tropical or subtropical climates

y=1, n=0

y

2.05

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

?=-1, n=0

y

3.01

Naturalized beyond native range y = 1*multiplier (see Append 2), n= question 2.05

n

3.02

Garden/amenity/disturbance weed y = 1*multiplier (see Append 2)

n=0

n

3.03

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

n=0

n

3.04

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

n=0

n

3.05

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

n=0

n

4.01

Produces spines, thorns or burrs

y=1, n=0

n

4.02

Allelopathic

y=1, n=0

n

4.03

Parasitic

y=1, n=0

n

4.04

Unpalatable to grazing animals

y=1, n=-1

4.05

Toxic to animals

y=1, n=0

n

4.06

Host for recognized pests and pathogens

y=1, n=0

y

4.07

Causes allergies or is otherwise toxic to humans

y=1, n=0

n

4.08

Creates a fire hazard in natural ecosystems

y=1, n=0

y

4.09

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

y=1, n=0

4.1

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

y=1, n=0

y

4.11

Climbing or smothering growth habit

y=1, n=0

n

4.12

Forms dense thickets

y=1, n=0

n

5.01

Aquatic

y=5, n=0

n

5.02

Grass

y=1, n=0

n

5.03

Nitrogen fixing woody plant

y=1, n=0

n

5.04

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

y=1, n=0

n

6.01

Evidence of substantial reproductive failure in native habitat

y=1, n=0

n

6.02

Produces viable seed.

y=1, n=-1

y

6.03

Hybridizes naturally

y=1, n=-1

6.04

Self-compatible or apomictic

y=1, n=-1

6.05

Requires specialist pollinators

y=-1, n=0

n

6.06

Reproduction by vegetative fragmentation

y=1, n=-1

n

6.07

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

See left

3

7.01

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

y=1, n=-1

n

7.02

Propagules dispersed intentionally by people

y=1, n=-1

y

7.03

Propagules likely to disperse as a produce contaminant

y=1, n=-1

n

7.04

Propagules adapted to wind dispersal

y=1, n=-1

n

7.05

Propagules water dispersed

y=1, n=-1

n

7.06

Propagules bird dispersed

y=1, n=-1

y

7.07

Propagules dispersed by other animals (externally)

y=1, n=-1

n

7.08

Propagules survive passage through the gut

y=1, n=-1

y

8.01

Prolific seed production (>1000/m2)

y=1, n=-1

n

8.02

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

y=1, n=-1

n

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

8.05

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

y=-1, n=1

Total score:

-3

Source

Notes

1.01

no evidence

1.02

no evidence

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/tax_search.pl?Dictyosperma+album (22 October 2003)

Africa: Mauritius

2.02

2.03

(1) Horticopia A-Z.Horticopia, Inc., Purcellville, VA. ISBN 1-887215-07-7. (2) http://www.floridata.com/ref/D/dict_alb.cfm (3)http://www.pacsoa.org.au/palms/Dictyosperma/album.html (4)http://palms.netfirms.com/cgi-bin/palmdb.cgi?dictyospermaalbum (5)http://www.floridagardener.com/palms/princesspalm.htm

(1) Hardiness Range 10B to 11 (2) Hardiness: USDA Zones 10B - 11. Does not tolerate frosts. (3)Habitat: Coastal forests. (4)Sea level to 600m (5)Drying winds can burn foliage

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/tax_search.pl?Dictyosperma+album (22 October 2003)

Native Distributional range: Africa: Mauritius

2.05

http://www.floridata.com/ref/D/dict_alb.cfm

This palm is a popular landscape item that is grown throughout the tropics.

3.01

no evidence

3.02

no evidence

3.03

no evidence

3.04

no evidence

3.05

no evidence

4.01

Horticopia A-Z.Horticopia, Inc., Purcellville, VA. ISBN 1-887215-07-7.

Trunk has no thorns

4.02

no evidence

4.03

no evidence

4.04

no evidence

4.05

no evidence

4.06

Annual Report, 1981, Mauritius Sugar Industry Research Institute. Annual Report, 1981, Mauritius Sugar Industry Research Institute., 1982, 76 pp.

AB: In the diseases section (40-47) it is noted that gumming (Xanthomonas campestris pv. vasculorum) was more severe than in any year since 1964 due to cultivation of the susceptible cultivar M 377/56 and favourable weather conditions. Foliar symptoms of the disease were also noted on the alternative hosts Dictyosperma album and Thysanolaena maxima. [a sugarcane disease]

4.07

Rouillard, G.; Guého, J. (1985) History of the horticultural, medicinal and economic plants of Mauritius. XII. [FT: Histoire des plantes d'intérêt horticole, médicinal et économique à l'Île Maurice. XII.] Revue Agricole et Sucrière de l'Île Maurice, 1985, Vol.64, No.2, pp.81-110, 16 ref.

AB: "Dictyosperma album var. album, used for palm cabbage production"

4.08

Horticopia A-Z.Horticopia, Inc., Purcellville, VA. ISBN 1-887215-07-7.

Attributes and Features - Highly flammable

4.09

(1)Horticopia A-Z.Horticopia, Inc., Purcellville, VA. ISBN 1-887215-07-7. (2)http://www.junglemusic.net/palms/dictyosperma-album.htm (3)http://www.desert-tropicals.com/Palm/Dictyosperma_album.html

(1)Exposure: Partial shade or partial sun to full sun (2)Full or part day sun (3)Sun Requirements: Light shade

4.1

(1) Horticopia A-Z.Horticopia, Inc., Purcellville, VA. ISBN 1-887215-07-7.
(2) http://www.thegreenescape.com/Merchant2/merchant.mv?Screen=
PROD&Store_Code=any&Product_Code=Dictyosperma_album_var_rubrum (3)http://palmdoctor.com/Palm_0f_The_Month/Dictyosperma_album.htm

(1) Soil Condition Loamy, sandy, clay, acidic, neutral, slightly alkaline, somewhat drought tolerant
(2) Soil Requirements:Widely adaptable but preferring rich, well drained soil. Responds well to fertilizing and regular watering (3)Its tolerability of many soil conditions makes it exceptionally adaptable 

4.11

single trunk palm

4.12

no evidence

5.01

terrestrial

5.02

palm; Arecaceae

5.03

no evidence

5.04

palm

6.01

Maunder, M.; Page, W.; Mauremootoo, J.; Payendee, R.; Mungroo, Y.; Maljkovic, A.; Vericel, C.; Lyte, B.
AA: Development Unit, Royal Botanic Gardens, Kew, Richmond, Surrey, UK. (2002) The decline and conservation management of the threatened endemic palms of the Mascarene Islands. Oryx, 2002, Vol.36, No.1, pp.56-65

AB: The conservation status of the five genera and 11 species of palm endemic to the Mascarene Islands (Mauritius, La Réunion and Rodriques) are reviewed. All species are threatened with extinction; nine taxa are classified as Critically Endangered and four as Endangered on the 2000 IUCN Red List. Two taxa survived as single wild specimens (Hyophorbe amaricaulis [H. lagenicaulis ] and Dictyosperma album var. conjugatum ); an additional seven taxa have wild populations of 100 or fewer. Although the historical phase of large-scale forest clearance has passed, the remaining palm populations in the Mascarenes are under threat from the effects of population fragmentation, invasive plants and animals, and high levels of seed predation that prevent natural regeneration. [The species does not show reproductive failure - it produces seeds but external factores of seed predation limit natural regeneration].

6.02

http://www.floridata.com/ref/D/dict_alb.cfm

Propagation: Propagate from seed, which germinates in 2-4 months

6.03

no evidence

6.04

no evidence

6.05

Kiew, R.; Muid, M. (1989) Bees and palms in Peninsular Malaysia. Principes, 1989, Vol.33, No.2, pp.74-77

AB: The following palms are known to be foraged on by Apis cerana : coconut, sago (Metroxylon sagu ), Manila palm (Veitchia merrillii ), MacArthur palm (Ptychosperma macarthuri ), betel nut (Areca catechu ), royal palm (Roystonea regia ), sugar palm (Arenga pinnata ), princess palm (Dictyosperma album ), Arenga westerhoutii, oil palm (Elaeis guineensis ). Apis dorsata and Trigona species also forage on a wide range of palms.

6.06

single trunk palm

6.07

(1)http://www.pacsoa.org.au/palms/Dictyosperma/album.html (2)Rate of Growth: Moderate

(1)Medium fast grower (2)http://www.floridagardener.com/palms/princesspalm.htm [estimate minimum for a small palm w/ med / fast growth]

7.01

not likely with large palm seed

7.02

http://www.floridata.com/ref/D/dict_alb.cfm

This palm is a popular landscape item that is grown throughout the tropics.

7.03

no evidence

7.04

not likely with large palm seed

7.05

no evidence

7.06

(1) Horticopia A-Z.Horticopia, Inc., Purcellville, VA. ISBN 1-887215-07-7.
(2) http://www.floridata.com/ref/D/dict_alb.cfm (3)http://mysite.mweb.co.za/residents/rudolphrj/palms/dictyosperma_alb.htm

(1) Fruit Composition: Fleshy, Fruit Shape: Oval, round
(2) The flowers are yellow to red and the fruits are bullet shaped and purple or black in color.
(3)Fruit : 18mm long egg shaped, dark red to black when ripe.
Seed : Egg shaped, pointed, with scar from the one end to the other.

7.07

Horticopia A-Z.Horticopia, Inc., Purcellville, VA. ISBN 1-887215-07-7.

Fruit Composition: Fleshy
Fruit Shape: Oval, round

7.08

assuming bird-dispersed

8.01

http://www.floridata.com/ref/D/dict_alb.cfm (2)http://mysite.mweb.co.za/residents/rudolphrj/palms/dictyosperma_alb.htm

seems prolific based on the picture (2)Fruit : 18mm long egg shaped, dark red to black when ripe.
Seed : Egg shaped, pointed, with scar from the one end to the other. [If fruit is 18 mm long with one seed in it - then probably not.]

8.02

http://www.rarepalmseeds.com/pix/DicAlb.shtml

easy to germinate and need up to 3 months to sprout.

8.03

no evidence of being controlled

8.04

unlikely, a single trunk palm; meristem is at top

8.05

no evidence