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

Tacca leontopetaloides (Tacca hawaiiensis, Tacca pinnatifida batflower, Polynesian arrowroot, east indian arrowroot)

Answer

1.01

Is the species highly domesticated?

y=-3, n=0

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

4.06

Host for recognized pests and pathogens

y=1, n=0

n

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

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

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

y

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

n

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

2

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

y

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

8.05

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

y=-1, n=1

Total score:

0

Source

Notes

1.01

[grown from tubers for >1000 years; possibly domesticated] Observations on Mile Atoll have shown there are 4 varieties or subvarieties, differing in stem and tuber colour and in the number of tubers produced/plant. The high nutritional value and overall popularity of arrowroot starch justify the re-introduction of the crop under coconut trees in copra plantations. A detailed report on past and present occurrence, importance, starch extraction techniques and plant utilization is in preparation.

Spennemann, D. H. R. 1992. Arrowroot production in the Marshall Islands: past, present, and future. New Zealand Journal of Crop and Horticultural Science 20:97 .

1.02

[No evidence of naturalizations.The species almost has a pantropical distribution.] (1)Also the exact origin is not known although thought to be in Malesia. It is widely distributed wild and sometimes cultivated throughout South East Asia and in the Pacific as far as Easter Island. (2)casually subspontaneous in Mauritius

(1)Plant resouces of south-east Asia. 1996. Eds, Flanch, M. & Rumawas. No 9. Bogor. Indonesia. (2)Baker. Flora of Mauritius and the Seychelles. L. Reeve and Co. London.

1.03

No evidence

2.01

(1)Origin: Paleotropics from western Africa to se Asia, Malesia. (2) The exact origin is not known although thought to be in Malesia. It is widely distributed wild and sometimes cultivated throughout South East Asia and in the Pacific as far as Easter Island. (3)native to Africa, S and SE Asia, N Australia, and S Pacific Islands

(1)http://florawww.eeb.uconn.edu/acc_num/199700062.html (2) Plant resouces of south-east Asia. 1996. Eds, Flanch, M. & Rumawas. No 9. Bogor. Indonesia. (3)http://hua.huh.harvard.edu/china/mss/volume24/TACCACEAE.published.pdf

2.02

2.03

(1)It rarely occurs in heavy shade and in primary forests, frequently in coastal vegetation, usually below 200 m, occasionally up to 1100 m altitude. (2)grown in humid tropical greenhouses

(1)Plant resouces of south-east Asia. 1996. Eds, Flanch, M. & Rumawas. No 9. Bogor. Indonesia.(2)http://www.ccnnwebdesign.com/garden/tacca/tacca.htm

2.04

(1)Origin: Paleotropics from western Africa to se Asia, Malesia. (2) The exact origin is not known although thought to be in Malesia. It is widely distributed wild and sometimes cultivated throughout South East Asia and in the Pacific as far as Easter Island.

(1)http://florawww.eeb.uconn.edu/acc_num/199700062.html (2) Plant resouces of south-east Asia. 1996. Eds, Flanch, M. & Rumawas. No 9. Bogor. Indonesia.

2.05

(1)Hawaii, (2)China, (3)USA

(1)http://www.hawaii-nation.org/canoe/pia.html (2)http://hua.huh.harvard.edu/china/mss/volume24/TACCACEAE.published.pdf (3)www.ccnnwebdesign.com/garden/tacca/tacca.htm

3.01

[No evidence of naturalizations.The species almost has a pantropical distribution.] (1)Also the exact origin is not known although thought to be in Malesia. It is widely distributed wild and sometimes cultivated throughout South East Asia and in the Pacific as far as Easter Island. (2)casually subspontaneous in Mauritius

(1)Plant resouces of south-east Asia. 1996. Eds, Flanch, M. & Rumawas. No 9. Bogor. Indonesia. (2)Baker. Flora of Mauritius and the Seychelles. L. Reeve and Co. London.

3.02

No evidence

3.03

Present (and native) in Indonesia but not an economic weed

Geographic Atlas of World Weeds, Holm, Pancho, Herberger, Pluncknett

3.04

No evidence

3.05

No evidence

4.01

No evidence

Plant resources of south-east Asia. 1996. Eds., Flanch, M. & Rumawas. No 9. Bogor. Indonesia.

4.02

No evidence

4.03

No evidence

4.04

No information.

4.05

Edible tubers [must be washed]

Whistler, A. 2000. Tropical Ornamentals. Timber Press.

4.06

Cercospora sp and Cercospora taccae are the fungi listed to be associated with T. leontopetaloides. Not found to be recognized pests.

http://nt.ars-grin.gov/fungaldatabases/all/FindRecOneFungusFrame.cfm

4.07

No evidence

4.08

lush evergreen foliage

4.09

(1)Plants like a protected, but fairly brightly lit situation. (2) It rarely occurs in heavy shade and in primary forests, frequently in coastal vegetation, usually below 200 m, occasionally up to 1100 m altitude. (3)open woods at low altitudes, in warm and shady places (4)Medium to low light

(1)http://florawww.eeb.uconn.edu/acc_num/199700062.html (2) Plant resources of south-east Asia. 1996. Eds., Flanch, M. & Rumawas. No 9. Bogor. Indonesia. (3)http://www.hawaii-nation.org/canoe/pia.html (4)http://sleepyoaks.com/tacca_chantrieri_bat_plant.htm

4.1

No information regarding soil types.

4.11

Probably not - not a vine.

4.12

No evidence

5.01

5.02

5.03

5.04

An herbaceous, aroid-like plant dying back to a large, rounded subterranean tuber.

http://florawww.eeb.uconn.edu/acc_num/199700062.html

6.01

'In Malesia flowering and fruiting may occur in all months of the year.'

Plant resources of south-east Asia. 1996. Eds., Flanch, M. & Rumawas. No 9. Bogor. Indonesia.

6.02

'Plants grown from seed first produce palmately incised young leaves… .'

Plant resources of south-east Asia. 1996. Eds., Flanch, M. & Rumawas. No 9. Bogor. Indonesia.

6.03

No information on hybridization.

6.04

Female plants bear more, and larger, tubers than male plants [dioescus?]

Spennemann, D. H. R. 1992. Arrowroot production in the Marshall Islands: past, present, and future. New Zealand Journal of Crop and Horticultural Science 20:97 .

6.05

'Most probably pollination is effected by insects.'

Plant resources of south-east Asia. 1996. Eds., Flanch, M. & Rumawas. No 9. Bogor. Indonesia.

6.06

'During the growing season the tuber is replaced by a new main tuber which arises from a downward-growing runner like thick rhizome at a lower level and remains dormant after the yearly death of the aerial parts of the original plant until the new growing season. Secondary smaller runners also forming tubers may emerge above the old tuber and spread downwards. This cycle takes about 8-10 months with 2-4 months of dormancy.'

Plant resources of south-east Asia. 1996. Eds., Flanch, M. & Rumawas. No 9. Bogor. Indonesia.

6.07

'Plants grown from seed first produce palmately incised young leaves are 3 lobed with each lobe pinnately lobed; such plants do not flower until 2 - 3 years old.''

Plant resources of south-east Asia. 1996. Eds., Flanch, M. & Rumawas. No 9. Bogor. Indonesia.

7.01

Propagules do not have any means of attachment.

Plant resources of south-east Asia. 1996. Eds., Flanch, M. & Rumawas. No 9. Bogor. Indonesia.

7.02

'Without doubt the most important distributor of east Indian arrowroot has been man, mainly by planting tubers.'

Plant resources of south-east Asia. 1996. Eds., Flanch, M. & Rumawas. No 9. Bogor. Indonesia.

7.03

Probably not as seeds are relatively large (5-8mm x 3-4mm x 1.5-3mm). Also tubers are used in the trade and not seeds. Each individual tuber weighs from 70 to 340 gm.

Plant resources of south-east Asia. 1996. Eds., Flanch, M. & Rumawas. No 9. Bogor. Indonesia.

7.04

pods will remain on the plant for quite a long time. Once they dry out or fall, remove them and split them open to remove the seeds.

http://www.ccnnwebdesign.com/garden/tacca/tacca.htm

7.05

(1) 'Seeds can be dispersed by sea water, the spongy testa enabling them to float for many months, but nothing is known about the influence of sea water on viability. Its occurrence on many island suggests the possibility of dispersal by sea. Fruits are eaten by white-eyed bid (Zosterops maasii), which might also disperse the seed.' (2)found near streams in the wild

(1) Plant resources of south-east Asia. 1996. Eds., Flanch, M. & Rumawas. No 9. Bogor. Indonesia. (2)http://www.hawaii-nation.org/canoe/pia.html

7.06

(1) 'Seeds can be dispersed by sea water, the spongy testa enabling them to float for many months, but nothing is known about the influence of sea water on viability. Its occurrence on many island suggests the possibility of dispersal by sea. Fruits are eaten by white-eyed bid (Zosterops maasii), which might also disperse the seed.' (2)Fruit a berry.

(1) Plant resources of south-east Asia. 1996. Eds., Flanch, M. & Rumawas. No 9. Bogor. Indonesia. (2) http://hua.huh.harvard.edu/china/mss/volume24/TACCACEAE.published.pdf

7.07

no evidence

7.08

fruit a berry

http://hua.huh.harvard.edu/china/mss/volume24/TACCACEAE.published.pdf

8.01

(1)Seed flattened, ovoid to ellipsoidal, 5-8 mm x 3-5 mm x 1.5-3mm , yellow brown but not surrounded by a spongy white aril. (2)One pod I opened had 6 seeds while another had 44

(1) Plant resources of south-east Asia. 1996. Eds., Flanch, M. & Rumawas. No 9. Bogor. Indonesia. (2)http://www.ccnnwebdesign.com/garden/tacca/tacca.htm

8.02

The fresher the seed, the better the germination.The age of the seed is an important factor in germination.

http://www.ccnnwebdesign.com/garden/tacca/tacca.htm

8.03

No evidence that the species is being controlled for.

8.04

No information.

8.05

Tacca's are known for damping off.

http://www.ccnnwebdesign.com/garden/tacca/tacca.htm