Pacific Island Ecosystems at Risk (PIER)


Alocasia cucullata


RISK ASSESSMENT RESULTS: High risk, score: 9


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

Alocasia cucullata (Lour.) G. Don (dwarf elephant ear, Chinese taro, Chinese ape)

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

y

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

y

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

y

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

y

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

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

4.08

Creates a fire hazard in natural ecosystems

y=1, n=0

n

4.09

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

y=1, n=0

y

4.1

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

y=1, n=0

n

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

y

6.01

Evidence of substantial reproductive failure in native habitat

y=1, n=0

n

6.02

Produces viable seed.

y=1, n=-1

6.03

Hybridizes naturally

y=1, n=-1

6.04

Self-compatible or apomictic

y=1, n=-1

n

6.05

Requires specialist pollinators

y=-1, n=0

y

6.06

Reproduction by vegetative fragmentation

y=1, n=-1

y

6.07

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

See left

7.01

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

y=1, n=-1

y

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

7.04

Propagules adapted to wind dispersal

y=1, n=-1

n

7.05

Propagules water dispersed

y=1, n=-1

y

7.06

Propagules bird dispersed

y=1, n=-1

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

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

8.03

Well controlled by herbicides

y=-1, n=1

8.04

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

y=1, n=-1

y

8.05

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

y=-1, n=1

Total score:

9

Supporting data:

Notes

Source

1.01

No evidence

1.02

Wild distribution: NE India, Sri Lanka to S China; in peninsular Malaysia naturalized.

http://mansfeld.ipk-gatersleben.de/Mansfeld/Taxonomy/datenvoll.afp?
module=mf&ID=botnam_19M168JSC&source=botnam&taxid=29351&akzanz=0

1.03

No evidence

2.01

(1)Origin: Burma, India (2)Wild distribution: NE India, Sri Lanka to S China; in peninsular Malaysia naturalized.

(1)http://www.plantdelights.com/Catalog/Current/Detail/04795.html (2)http://mansfeld.ipk-gatersleben.de/Mansfeld/Taxonomy/datenvoll.afp?
module=mf&ID=botnam_19M168JSC&source=botnam&taxid=29351&akzanz=0

2.02

2.03

(1)Zone: 7b-10 (2)Found at reasonably high altitudes in China and will take several degrees of frost. (3)0-1200+ m; lowlands of both slopes to at least as high as Valle Central. Fl. ?. Native to S and SE Asia.

(1)http://www.plantdelights.com/Catalog/Current/Detail/04795.html (2)http://www.mulu.co.uk/itemdisplay.php?itemid=7 (3)http://www.mobot.org/MOBOT/research/treat/alocasia.shtml

2.04

(1)Origin: Burma, India (2)Wild distribution: NE India, Sri Lanka to S China; in peninsular Malaysia naturalized.

(1)http://www.plantdelights.com/Catalog/Current/Detail/04795.html (2)http://mansfeld.ipk-gatersleben.de/Mansfeld/Taxonomy/datenvoll.afp?
module=mf&ID=botnam_19M168JSC&source=botnam&taxid=29351&akzanz=0

2.05

(1)In India (Assam and Bengal), Sri Lanka, Myanmar, Thailand, and peninsular Malaysia cultivated for the corms. Mostly used to produce starch though better known for its medicinal value among Chinese herbalists. Domesticated possibly in India or the Indo-Chinese region. (2)Cultivated in the U.S.

(1)http://mansfeld.ipk-gatersleben.de/Mansfeld/Taxonomy/datenvoll.afp?
module=mf&ID=botnam_19M168JSC&source=botnam&taxid=29351&akzanz=0 (2)http://plants.usda.gov/

3.01

(1)Wild distribution: NE India, Sri Lanka to S China; in peninsular Malaysia naturalized. (2)naturalized throughout s.e. Asia

(1)http://mansfeld.ipk-gatersleben.de/Mansfeld/Taxonomy/datenvoll.afp?
module=mf&ID=botnam_19M168JSC&source=botnam&taxid=29351&akzanz=0 (2)http://www.ars-grin.gov/cgi-bin/npgs/html/tax_search.pl?Alocasia+cucullata

3.02

(1)may be invasive [spreading in gardens but deliberately planted there] (2)Well behaved garden specimen (3)No environmental problems.

(1)http://msucares.com/lawn/garden/flowers/perennial/selection.html (2)http://dollarnursery.net/Alocasia-Cucullata.htm (3)http://www.zoneten.com/water.htm

3.03

No evidence

3.04

No evidence

3.05

(1) Alocasia brisbanensis is listed as a weed in western Australia

(2) Alocasia indica v. Metallica and Alocasia macrorrhizos were registered as environmental weed

(1) http://members.iinet.net.au/~weeds/western_weeds/alstoemeia_araceae.htm

(2) http://www.warringah.nsw.gov.au/weed_control.htm

4.01

No evidence of such structures.

http://www.ars-grin.gov/cgi-bin/npgs/html/tax_search.pl?Alocasia+cucullata

4.02

No evidence

4.03

No evidence

4.04

Don’t know

4.05

(1) [In general about Alocasia] Toxic element: acido oxalic, asparagin, a protein located in this plant. Note: the leaves and stems are most dangerous if they are consumed in great amount. (2)AB: Nai Habarala is not documented as a poisonous plant. However, we report two cases of fatal poisoning following ingestion of its fruit. The clinical manifestations have a similarity to cyanogenic glycoside poisoning. [Not sure whether the above refers to toxicity in livestock as well as humans].

(1)http://translate.google.com/translate?hl=en&sl=es&u=http://pcs.adam.com/ency/article/002868.htm
&prev=/search%3Fq%3DAlocasia%2Bcucullata%26start%3D10%26hl%3Den%26lr%3D%26ie%3DUTF-8%26sa%3DN (2)TI: Is Nai Habarala (Alocasia cucullata) a poisonous plant? AU: Goonasekera, CDA; Vasanthathilake, VWJK; Ratnatunga, N; Seneviratne, CAS SO:Toxicon. June 1993. v. 31 (6) p. 813-816

4.06

Cercospora colocasiae causes Cercospora Leafspot on taro (Colocasia esculenta) as well as Chinese taro (Alocasia cucullata)

http://www.extento.hawaii.edu/kbase/crop/Type/cer_prim.htm

4.07

(1) [In general about Alocasia] Toxic element: acido oxalic, asparagin, a protein located in this plant. Note: the leaves and stems are most dangerous if they are consumed in great amount. (2)AB: Nai Habarala is not documented as a poisonous plant. However, we report two cases of fatal poisoning following ingestion of its fruit. The clinical manifestations have a similarity to cyanogenic glycoside poisoning. (3)no hazards to humans

(1)http://translate.google.com/translate?hl=en&sl=es&u=http://pcs.adam.com/ency/article/002868.htm
&prev=/search%3Fq%3DAlocasia%2Bcucullata%26start%3D10%26hl%3Den%26lr%3D%26ie%3DUTF-8%26sa%3DN (2)TI: Is Nai Habarala (Alocasia cucullata) a poisonous plant? AU: Goonasekera, CDA; Vasanthathilake, VWJK; Ratnatunga, N; Seneviratne, CAS SO:Toxicon. June 1993. v. 31 (6) p. 813-816 (3)http://www.zoneten.com/water.htm

4.08

(1)likes moisture retentive soils. (2)All have bold leaves held tall on fleshy long soft 'wet' stems

(1)http://www.durionursery.com/bulbs.htm (2)http://mgonline.com/alocasia.html

4.09

(1)Part Sun to Light Shade (2)Prefers semi shade.

(1)http://www.plantdelights.com/Catalog/Current/Detail/04795.html (2)http://www.landsendtexotics.co.nz/cat_aroids.shtml

4.1

Likes well-drained and or moisture retentive soil.

http://www.durionursery.com/bulbs.htm

4.11

The trunk is disproportionately thick compared to the tiny leaves. It seems to develop a climbing habit. [No evidence of smothering habit].

http://www.aroid.org/gallery/kozminski/Alocasia/cucullata.html

4.12

No evidence

5.01

Araceae

5.02

Araceae

5.03

herbaceous

5.04

The root is a corm.

6.01

"sparingly naturalized in shady understory of surrounding forests"; "common herb on roadside bank across from Araki hotel in understory of alien forest, ubiquitous along roads throughout the valley"

http://hbs.bishopmuseum.org/pdf/op74.pdf

6.02

sold as young adult plants [no seeds seen]

http://www.lorescotropicalplants.homestead.com/ElephantEarsPage.html

6.03

many other species and hybrids available [don't know if natural]

http://msucares.com/lawn/garden/flowers/perennial/selection.html

6.04

Probably not - characteristic of the genus Aroid is unisexual flowers.

Wagner, W.L., D.R. Herbst and S.H. Sohmer. 1999. Manual of the flowering plants of Hawai`i. Revised edition. University of Hawai`i Press, Honolulu.

6.05

Alocasia are pollinated by specific flies, one plant species have 2-3 species of specific pollinators

http://neco.biology.kyushu-u.ac.jp/~miyake/work/work3.html

6.06

p.8 "Chinese taro suckers freely and can spread vegetatively in that manner. Even small pieces of stem, root, or rhizome in the soil are enough to give rise to new plants and the species appears to reach new localities through movement of soil by humans."

http://hbs.bishopmuseum.org/pdf/op74.pdf

6.07

Fast growing. [but not propagated by seeds]

http://www.landsendtexotics.co.nz/cat_aroids.shtml

7.01

p.8 "common herb on roadside bank across from Araki hotel in understory of alien forest, ubiquitous along roads throughout the valley"; "Chinese taro suckers freely and can spread vegetatively in that manner. Even small pieces of stem, root, or rhizome in the soil are enough to give rise to new plants and the species appears to reach new localities through movement of soil by humans."

http://hbs.bishopmuseum.org/pdf/op74.pdf

7.02

Ornamental and consumed as human food.

http://www.ars-grin.gov/cgi-bin/npgs/html/tax_search.pl?Alocasia+cucullata

7.03

Corms of this species are used as food in India. [might spread from discarded food pieces ]

http://www.zoneten.com/water.htm

7.04

genus Alocasia fruit is a berry.

7.05

aquatic plants [corms/fragments presumed dispersed during stream bank erosion]

http://www.zoneten.com/water.htm

7.06

fruit is a berry. [but not seen]

Wagner, W.L., D.R. Herbst and S.H. Sohmer. 1999. Manual of the flowering plants of Hawai`i. Revised edition. University of Hawai`i Press, Honolulu.

7.07

no evidence that the propagules have any means of attachment.

7.08

fruit is a berry. [but not seen]

Wagner, W.L., D.R. Herbst and S.H. Sohmer. 1999. Manual of the flowering plants of Hawai`i. Revised edition. University of Hawai`i Press, Honolulu.

8.01

fruits not seen [rare or sterile]

8.02

No evidence regarding seedbank.

8.03

No evidence that the species is being controlled for.

8.04

p.8 " Even small pieces of stem, root, or rhizome in the soil are enough to give rise to new plants and the species appears to reach new localities through movement of soil by humans."

http://hbs.bishopmuseum.org/pdf/op74.pdf

8.05

Don’t know


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