Pacific Island Ecosystems at Risk (PIER)


Costus woodsonii


RISK ASSESSMENT RESULTS: High risk, score: 11


Australian/New Zealand Weed Risk Assessment adapted for Hawai‘i.
Information on Risk Assessments
Original risk assessment

Costus woodsonii Maas. Family - Costaceae. Common Names(s) - Indian-Head Ginger. Synonym(s) - Misapplied: C. spicatus, C. spiralis.

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

y

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

n

0

3.03

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

n=0

n

0

3.04

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

n=0

n

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

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

4.10

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

y=1, n=0

y

1

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

6.04

Self-compatible or apomictic

y=1, n=-1

y

1

6.05

Requires specialist pollinators

y=-1, n=0

y

-1

6.06

Reproduction by vegetative fragmentation

y=1, n=-1

y

1

6.07

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

See left

1

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

7.04

Propagules adapted to wind dispersal

y=1, n=-1

n

-1

7.05

Propagules water dispersed

y=1, n=-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

n

-1

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

1

8.05

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

y=-1, n=1

Total score:

11

Supporting data:

Notes

Source

1.01

No evidence

 

1.02

1.03

2.01

(1)A widespread species native to the lowlands and coastal areas of Nicaragua, Costa Rica, Panama and the Pacific coastline of Colombia.

(1)Staples, G. W. and D. R. Herbst. 2005. A Tropical Garden Flora. Plants Cultivated in the Hawaiian Islands and Other Pacific Islands. Bishop Museum Press. Honolulu, HI.

2.02

Native range well known and within tropics.

 

2.03

(1)Zones 9-11.

(1)Llamas, K. A. 2003. Tropical Flowering Plants: A Guide to Identification and Cultivation. Timber Press. Portland, OR.

2.04

(1)A widespread species native to the lowlands and coastal areas of Nicaragua, Costa Rica, Panama and the Pacific coastline of Colombia.

(1)Staples, G. W. and D. R. Herbst. 2005. A Tropical Garden Flora. Plants Cultivated in the Hawaiian Islands and Other Pacific Islands. Bishop Museum Press. Honolulu, HI.

2.05

(1)Cultivated in the Marquesas (2)Several spiral gingers are available locally, one of the most popular with south Florida growers being Costus woodsonii (3)C. woodsonii is occasionally cultivated in Hawaii for its red-bracted inflorescences

(1)http://botany.si.edu/pacificislandbiodiversity/marquesasflora/results.cfm?genus=Costus&specificepithet=woodsonii&rank=&epithet1= [Accessed 23 May 2008] (2)http://miami-dade.ifas.ufl.edu/old/programs/urbanhort/publications/Caulkins%20pdf/Calkins%2039%20Gingers%20and%20Heliconias.pdf [Accessed 23 May 2008] (3)Staples, G. W. and D. R. Herbst. 2005. A Tropical Garden Flora. Plants Cultivated in the Hawaiian Islands and Other Pacific Islands. Bishop Museum Press. Honolulu, HI.

3.01

(1)Native to tropical America from lowland Nicaragua to the Pacific coast of Colombia, this species was first planted (as C. spicatus) in lower ‘Aihualama in 1925, where it is now grows in dense stands. This species spreads locally by plantlets that develop on old inflorescences. It has also spread to other areas of the Arboretum, some quite remote from the original planting, suggesting reproduction by seeds. The leaves are spirally arranged, thick, and dark green, the bracts dark red, and the flowers red-orange. This species was mentioned by Wagner et al. (1999: 1381) as escaping from Lyon Arboretum.(2)Red spiral flag is native from Nicaragua to Colombia (Whistler, 2000: 155). It occurs in scattered populations on windward Haleakalä at low elevations from Waipi‘o to Kïpahulu. (3)COOK ISLANDS STATUS: Introduced - Recent, Naturalised (Rarotonga); Land, lowlands, gardens

(1)Daehler, C. C. and R. F. Baker. 2006. New records of naturalized and naturalizing plants around Lyon Arboretum, Mānoa Valley, O‘ahu. In: Evenhuis, Neal L. and Eldredge, Lucias G., eds. Records of the Hawaii Biological Survey for 2004-2005. Part 1: Articles. Bishop Museum Occasional Papers 87:3-18. (2)Oppenheimer, H. L. 2003. New Hawaiian plant records for 2003. In: Evenhuis, Neal L. and Eldredge, Lucias G., eds. Records of the Hawaii Biological Survey for 2003. Part 2: Notes. Bishop Museum Occasional Papers 79: 8-20. (3)McCormack, Gerald. 2007. Cook Islands biodiversity and natural heritage. On-line database. Available from http://cookislands.bishopmuseum.org/species.asp?id=14119 [Accessed 23 May 2008]

3.02

(1)No evidence

(1)http://www.hear.org/gcw/species/costus_woodsonii/ [Accessed 23 May 2008]

3.03

(1)No evidence

(1)http://www.hear.org/gcw/species/costus_woodsonii/ [Accessed 23 May 2008]

3.04

(1)No evidence

(1)http://www.hear.org/gcw/species/costus_woodsonii/ [Accessed 23 May 2008]

3.05

(1)Costus speciosus (crepe or wild ginger) was seen naturalizing on Tutuila. This is a potentially troublesome species that reproduces vegetatively and can grow in either full sun or shaded forest understories. At least in the A'oloau area of Tutuila it seemed to thrive in areas of disturbance (in this case an abandoned orchard that was being turned into pasture). It is a weedy species in French Polynesia.

(1)Space, J. C. and T. Flynn. 2002. Report to the Government of Samoa on invasive plant species of environmental concern. USDA Forest Service, Honolulu. 83 pp.

4.01

(1)No evidence

(1)Gargiullo, M. B., B. L. Magnuson and L. D. Kimball. 2008. A Field Guide to Plants of Costa Rica. Oxford University Press. New York.

4.02

No evidence of allelopathy in genus

 

4.03

(1)No evidence

(1)Gargiullo, M. B., B. L. Magnuson and L. D. Kimball. 2008. A Field Guide to Plants of Costa Rica. Oxford University Press. New York.

4.04

(1) The yellow flowers that emerge from the red cones are edible [unknown for foliage]

(1)http://www.rareflora.com/costuswood.html [Accessed 23 May 2008]

4.05

(1)Family and genus not known for toxicity

(1)Zomlefer, W. B. 1994. Guide to Flowering Plant Families. The University of North Carolina Press. Chapel Hill, NC.

4.06

Unknown [no information on pathogens of this species]

 

4.07

No evidence

4.08

(1)Herb 1-2 m tall [succulent, ginger-like plant often growing in moist understory of forest]

(1)Gargiullo, M. B., B. L. Magnuson and L. D. Kimball. 2008. A Field Guide to Plants of Costa Rica. Oxford University Press. New York.

4.09

(1)This aggressive species grows in full sun, even in beach areas on sandy soils, but truly does it best where shade, ample moisture, and a deep, fertile soil are available.

(1)Staples, G. W. and D. R. Herbst. 2005. A Tropical Garden Flora. Plants Cultivated in the Hawaiian Islands and Other Pacific Islands. Bishop Museum Press. Honolulu, HI.

4.10

(1)This aggressive species grows in full sun, even in beach areas on sandy soils, but truly does it best where shade, ample moisture, and a deep, fertile soil are available.

(1)Staples, G. W. and D. R. Herbst. 2005. A Tropical Garden Flora. Plants Cultivated in the Hawaiian Islands and Other Pacific Islands. Bishop Museum Press. Honolulu, HI.

4.11

(1)Herb 1-2 m tall

(1)Gargiullo, M. B., B. L. Magnuson and L. D. Kimball. 2008. A Field Guide to Plants of Costa Rica. Oxford University Press. New York.

4.12

(1)"this species was first planted (as C. spicatus) in lower ‘Aihualama in 1925, where it is now grows in dense stands."

(1)Daehler, C. C. and R. F. Baker. 2006. New records of naturalized and naturalizing plants around Lyon Arboretum, Mānoa Valley, O‘ahu. In: Evenhuis, Neal L. and Eldredge, Lucias G., eds. Records of the Hawaii Biological Survey for 2004-2005. Part 1: Articles. Bishop Museum Occasional Papers 87:3-18.

5.01

Terrestrial

5.02

Costaceae

5.03

Costaceae

5.04

(1)Herb 1-2 m tall, colonial from underground stems [spreads by rhizomes, not tubers, corms or bulbs]

(1)Gargiullo, M. B., B. L. Magnuson and L. D. Kimball. 2008. A Field Guide to Plants of Costa Rica. Oxford University Press. New York.

6.01

(1)No evidence

(1)Schemske, D. W. 1980. The Evolutionary Significance of Extrafloral Nectar Production by Costus Woodsonii (Zingiberaceae): An Experimental Analysis of Ant Protection. The Journal of Ecology, Vol. 68(3): 959-967.

6.02

(1)It has also spread to other areas of the Arboretum, some quite remote from the original planting, suggesting reproduction by seeds.(2)Fruit white containing black seeds with afleshy, white aril. (3)1940:"Costus spicatus[C. woodsonii]. The Panamanian candle ginger propagates readily from plantlets and lalas that form after the spike has withered. Seed, however, seems to be formed rather sparingly. What seed there is has apparently been found by the birds, and quite a number of young plants were found growing in the eucalyptus forest in Aihualama."

(1)Daehler, C. C. and R. F. Baker. 2006. New records of naturalized and naturalizing plants around Lyon Arboretum, Mānoa Valley, O‘ahu. In: Evenhuis, Neal L. and Eldredge, Lucias G., eds. Records of the Hawaii Biological Survey for 2004-2005. Part 1: Articles. Bishop Museum Occasional Papers 87:3-18. (2)Gargiullo, M. B., B. L. Magnuson and L. D. Kimball. 2008. A Field Guide to Plants of Costa Rica. Oxford University Press. New York. (3)http://www.botany.hawaii.edu/herbarium/digitallib/collections/hlaplants/pdfs/Cot_Costus_woodsonii_w.pdf [Accessed 27 May 2008]

6.03

Unknown (1)"Many species of Costus are sympatric and are visited by the same pollinators (Schemske 1981; pers. Obs.). Hybridization has been described has been described for species of Costus within each section (Maas 1972, 1977)…" [No evidence for C. woodsonii, but possible within species of genus]

(1)Sytsma, K. J. and R. W. Pippen. 1985. Morphology and Pollination Biology of an Intersectional Hybrid of Costus (Costaceae). Systematic Botany 10(3): 353-362.

6.04

(1)Although the breeding system of Costus woodsonii is unknown, three congeners studies in Panama have a high level of self compatibility (D. W. Schemske, unpublished). [probably self-compatible]

(1)Schemske, D. W. 1980. The Evolutionary Significance of Extrafloral Nectar Production by Costus Woodsonii (Zingiberaceae): An Experimental Analysis of Ant Protection. The Journal of Ecology, Vol. 68(3): 959-967.

6.05

(1)The species Costus woodsonii is a hummingbird-pollinated, terrestrial herb...If C. woodsonii is self-compatible, the 1-4 fold greater pollination rate of controls in the wet season than in the dry season may be the result of pollination by the ant Wasmannia auropunctata, which was often observed in flowers. [floral morphology adapted for hummingbirds, but seed set suggests ants and possibly other insects could provide effective pollination] (2)Of the scores of potential pollinators in the tropical forest, each Costus species is pollinated by a limited number of taxa, indicating a high level of specialization by these plants to their pollinators.

(1)Schemske, D. W. 1980. The Evolutionary Significance of Extrafloral Nectar Production by Costus Woodsonii (Zingiberaceae): An Experimental Analysis of Ant Protection. The Journal of Ecology, Vol. 68(3): 959-967. (2)Kay, K. M. and D. W. Schemske. 2003. Pollinator Assemblages and Visitation Rates for 11 Species of Neotropical Costus (Costaceae). BIOTROPICA 35(2): 198–207.

6.06

(1)This species spreads locally by plantlets that develop on old inflorescences.

(1)Daehler, C. C. and R. F. Baker. 2006. New records of naturalized and naturalizing plants around Lyon Arboretum, Mānoa Valley, O‘ahu. In: Evenhuis, Neal L. and Eldredge, Lucias G., eds. Records of the Hawaii Biological Survey for 2004-2005. Part 1: Articles. Bishop Museum Occasional Papers 87:3-18.

6.07

(1)"makes a fast-growing background planting…inflorescences are produced year-round…easily propagated by shoots that develop on the inflorescences…"[fast growth rate and ability to spread vegetatively suggest species can reproduce in less than 1 year]

(1)Staples, G. W. and D. R. Herbst. 2005. A Tropical Garden Flora. Plants Cultivated in the Hawaiian Islands and Other Pacific Islands. Bishop Museum Press. Honolulu, HI.

7.01

Seeds that lack means of attachment make unintentional dispersal highly unlikely

 

7.02

(1)"widely cultivated in the tropics for its yellow to orange flowers" [popular ornamental]

(1)Whistler, W. A. 2000. Tropical Ornamentals. A Guide. Timber Press. Portland, OR.

7.03

Possibly if used in cut flower arrangements (1)Place your order online so we can deliver fresh Hawaiian flowers -- Heliconias Bihai, Heliconia Caribaeas, Heliconia Rostrata, Birds of paradise, Musas, Calatheas, Gingers, and Costus to your home. Take a look at the photos and pictures of each flower, and see what you want to plant or buy.

(1)http://www.agrotropical.andes.com/ [Accessed 27 May 2008]

7.04

(1)The black seeds are surrounded by a white fleshy aril, and are dispersed by birds.

(1)Schemske, D. W. 1980. The Evolutionary Significance of Extrafloral Nectar Production by Costus Woodsonii (Zingiberaceae): An Experimental Analysis of Ant Protection. The Journal of Ecology, Vol. 68(3): 959-967.

7.05

(1)"The seeds of Costus are 1-2 mm long and thus are the smallest of all Zingiberales…Dispersal by water currents may also occur" [Possible small seeds may disperse in water if growing in riparian areas]

(1)Kubitzki, K., K.U. Kramer, P.S. Green, J. G. Rohwer, V. Bittrich, H. Huber, J. W. Kadereit, and C. Jeffrey. 1998. The families and genera of vascular plants. Volume IV. Flowering Plants. Monocotyledons. Alismatanae and Commelinanae (except Gramineae). Springer-Verlag. Berlin, Germany.

7.06

(1)The black seeds are surrounded by a white fleshy aril, and are dispersed by birds.

(1)Schemske, D. W. 1980. The Evolutionary Significance of Extrafloral Nectar Production by Costus Woodsonii (Zingiberaceae): An Experimental Analysis of Ant Protection. The Journal of Ecology, Vol. 68(3): 959-967.

7.07

No means of external attachment

 

7.08

(1)The black seeds are surrounded by a white fleshy aril, and are dispersed by birds.

(1)Schemske, D. W. 1980. The Evolutionary Significance of Extrafloral Nectar Production by Costus Woodsonii (Zingiberaceae): An Experimental Analysis of Ant Protection. The Journal of Ecology, Vol. 68(3): 959-967.

8.01

(1)1940:"Costus spicatus[C. woodsonii]. The Panamanian candle ginger propagates readily from plantlets and lalas that form after the spike has withered. Seed, however, seems to be formed rather sparingly. What seed there is has apparently been found by the birds, and quite a number of young plants were found growing in the eucalyptus forest in Aihualama."

(1)http://www.botany.hawaii.edu/herbarium/digitallib/collections/hlaplants/pdfs/Cot_Costus_woodsonii_w.pdf [Accessed 27 May 2008]

8.02

Unknown [no information on seed banks for this species]

 

8.03

Unknown [no information on control with herbicides]

 

8.04

(1)"Its rhizomes are robust and invasive, and once established they are difficult to remove…easily propagated by shoots that develop on the inflorescences." (2)"Unless something drastic happened to the rhizome mass (like bugs ate it) it should pop back out soon. I have Costus Barbatus, Costus woodsonii and variegated Costus amazonicus in the ground here in Gainesville that come back every year after freezing to the ground. I have even had a small amount of luck getting COstus osae Red Rose and Costus Emerald Chalice to come back in very protected locations up close to the house."..."Here's a little secret that I learned from having to compost a lot of costus that I pruned out of the greenhouse almost continuously: When you trim off spent (still green, unfrozen) stalks, cut them into pieces about 8-10 inches long and throw them onto a compost heap (also do this with frosted stalks! Ambersky is right!) Wait til about May and you will probably have a whole lot of little baby volunteer gingers coming up from those cut pieces in the compost pile." [comments from gardeners in Mainland US]

(1)Staples, G. W. and D. R. Herbst. 2005. A Tropical Garden Flora. Plants Cultivated in the Hawaiian Islands and Other Pacific Islands. Bishop Museum Press. Honolulu, HI (2)http://forums.gardenweb.com/forums/load/flgard/msg031154335722.html [Accessed 27 May 2008]

8.05

Unknown


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