Costus dubius. Common name - costus. Synonyms- Zingiber dubius, Costus albus, Costus edulis, Costus trachyphyllus. Family - Costaceae

Answer

Score

1.01

Is the species highly domesticated?

n

0

1.02

Has the species become naturalized where grown?

1.03

Does the species have weedy races?

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”

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

2.04

Native or naturalized in regions with tropical or subtropical climates

y

1

2.05

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

n

3.01

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

0

3.02

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

n

0

3.03

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

n

0

3.04

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

n

0

3.05

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

y

2

4.01

Produces spines, thorns or burrs

n

0

4.02

Allelopathic

n

0

4.03

Parasitic

n

0

4.04

Unpalatable to grazing animals

4.05

Toxic to animals

n

0

4.06

Host for recognized pests and pathogens

n

0

4.07

Causes allergies or is otherwise toxic to humans

n

0

4.08

Creates a fire hazard in natural ecosystems

n

0

4.09

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

y

1

4.1

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

4.11

Climbing or smothering growth habit

n

0

4.12

Forms dense thickets

y

1

5.01

Aquatic

n

0

5.02

Grass

n

0

5.03

Nitrogen fixing woody plant

n

0

5.04

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

n

0

6.01

Evidence of substantial reproductive failure in native habitat

n

0

6.02

Produces viable seed.

y

1

6.03

Hybridizes naturally

6.04

Self-compatible or apomictic

6.05

Requires specialist pollinators

n

0

6.06

Reproduction by vegetative fragmentation

y

1

6.07

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

1

1

7.01

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

n

-1

7.02

Propagules dispersed intentionally by people

y

1

7.03

Propagules likely to disperse as a produce contaminant

n

-1

7.04

Propagules adapted to wind dispersal

n

-1

7.05

Propagules water dispersed

7.06

Propagules bird dispersed

7.07

Propagules dispersed by other animals (externally)

7.08

Propagules survive passage through the gut

8.01

Prolific seed production (>1000/m2)

8.02

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

8.03

Well controlled by herbicides

8.04

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

y

1

8.05

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

Total score:

8

Notes

Source

1.01

No evidence

1.02

1.03

2.01

Native to tropical Africa.

http://www.botany.hawaii.edu/herbarium/digitallib/collections/hlaplants/pdf/Cot_Costus_dubius_w.pdf

2.02

Native to tropical Africa.

http://www.botany.hawaii.edu/herbarium/digitallib/collections/hlaplants/pdf/Cot_Costus_dubius_w.pdf

2.03

(1)Hardiness has not been fully tested, but based on it's relative ease of cultivation and survival in a cool greenhouse, I am guessing hardiness as zone 9 and that it would come back okay from occasional light freezes.
(2) 'I tested this species outdoors for hardiness in our mild winter of 2005 and it did not come back at all from a large clump in a fairly protected area., so I do not believe it is hardy north of zone 10.' (3)Tested for winter hardiness by Tom Wood near Gainesville, Florida - zone 8b-9, did not survive. (4)Grows in Ghana from 400-750 m and in forest in Tanzania at 1150 m. (5)Grows at about 200 m in the Lyon Arboretum, Hawaii. [Yes, based on elevational range]

(1) http://www.gingersrus.com/cart/index.php?productID=3597 (2)http://www.gingersrus.com/DataSheet.php?PID=3597 (4)http://mobot.mobot.org/cgi-bin/search_vast (5)Daehler, C.Curtis. and Baker, Ray. 2006. New records of naturalized and naturalizing plants around Lyon Arboretum, Manoa Valley, Oahu. Bishop Museum Occasional Papers. 87: 3-18

2.04

Native to tropical Africa.

http://www.botany.hawaii.edu/herbarium/digitallib/collections/hlaplants/pdf/Cot_Costus_dubius_w.pdf

2.05

Introduced to several botanical gardens. (1)BOTANICAL GARDENS: (Gingers Only - Listing of locations where this plant can be seen.)
Fairchild Tropical Gardens, Coral Gables (Miami), Florida, USA
Marie Selby Botanical Gardens, Sarasota, Florida, USA
National Botanic Garden of Belgium, Belgium
New York Botanical Garden,
Royal Botanic Garden of Edinburgh, Edinburgh, Scotland, UK (2)At Lyon Arboretum, Hawaii. [No other evidence of introductions other than botanical gardens].

(1)http://www.gingersrus.com/DataSheet.php?PID=3597 (2)http://www.botany.hawaii.edu/herbarium/digitallib/collections/hlaplants/pdf/Cot_Costus_dubius_w.pdf

3.01

(1)Introduced to several botanical gardens but no evidence of naturalizing here. (1)BOTANICAL GARDENS:
Fairchild Tropical Gardens, Coral Gables (Miami), Florida, USA
Marie Selby Botanical Gardens, Sarasota, Florida, USA
National Botanic Garden of Belgium, Belgium
New York Botanical Garden,
Royal Botanic Garden of Edinburgh, Edinburgh, Scotland, UK (2)In Lyon Arboretum - "this plant has become a mojor problem wherever planted. It produces copius seeds." "Growing wild in Oplismenus grass," [But no evidence of spread outside of the Arboretum ].

(1)http://www.gingersrus.com/DataSheet.php?PID=3597 (2)Daehler, C.Curtis. and Baker, Ray. 2006. New records of naturalized and naturalizing plants around Lyon Arboretum, Manoa Valley, Oahu. Bishop Museum Occasional Papers. 87: 3-18

3.02

No evidence

3.03

No evidence

3.04

No evidence

3.05

Costus speciosus is listed to be invasive on some Pacific Islands.

http://www.hear.org/pier/species/costus_speciosus.htm

4.01

No evidence

4.02

No evidence

4.03

No evidence

http://www.omnisterra.com/bot/pp_home.cgi

4.04

Don’t know

4.05

No evidence

4.06

No evidence of associated pests or pathogens.

Farr, D.F., Rossman, A.Y., Palm, M.E., & McCray, E.B. (n.d.) Fungal Databases, Systematic Botany & Mycology Laboratory, ARS, USDA. Retrieved April 7, 2006, from http://nt.ars-grin.gov/fungaldatabases/

4.07

No evidence

4.08

Probably not - succulent herb with fleshy leaves and petals - grows near river banks.

http://www.gingersrus.com/DataSheet.php?PID=3597

4.09

(1) 'This seems to be a sun loving Costus species, and I recommend growing it in partial sun.' (2)"Almost all speceis are forest dwellers and have traditionally been grown in shade." [No further evidence regarding light requirements].

(1)http://www.gingersrus.com/DataSheet.php?PID=3597 (2)Branney. T M E. Hardy Gingers. 2005. Timber Press. Cambridge.Pg 78.

4.1

No evidence regarding soil requirements.

4.11

Perennial succulent herb.

http://www.gingersrus.com/DataSheet.php?PID=3597

4.12

based on photos - spreads vegetatively as dense thickets

(1)http://www.gingersrus.com/images/ImageFrame.php?ImageID=10677 (2)http://www.gingersrus.com/images/ImageFrame.php?ImageID=12661

5.01

Perennial succulent herb.

http://www.gingersrus.com/DataSheet.php?PID=3597

5.02

5.03

No evidence

5.04

Perennial succulent herb with underground rhizome.

http://www.gingersrus.com/DataSheet.php?PID=3597

6.01

No evidence

6.02

In Lyon Arboretum - "this plant has become a major problem wherever planted. It produces copius seeds."

Daehler, C.Curtis. and Baker, Ray. 2006. New records of naturalized and naturalizing plants around Lyon Arboretum, Manoa Valley, Oahu. Bishop Museum Occasional Papers. 87: 3-18

6.03

Don’t know.

6.04

Don’t know.

6.05

Probably not - "… The African-neotropical clade is composed entirely of the genus costus, moreover, there is support for previously recognized subgeneric groupings within the Costus clade. Evolutionary trends in floral morphology show that close associations with pollinators have evolved several times from an ancestral generalist pollinator floral form. Bee pollination has evolved once in the family, arising in Africa from an open-flowerd (generalist) ancestor. Bird pollination has evolved once in the family, arising in Africa from an open-flowered (generalist) ancestor. Bird pollination has evolved multiple times once from an open-flowered ancestor in Southeast Asia and multiple times from a bee-pollinated ancestor in the neotropics...." [Costus dubius is from Africa and belongs to the section costus (versus section ornithophilus which is pollinated by hummingbirds)].

Specht, C D. 2006. Systematics and Evolution of the Tropical Monocot Family Costaceae (Zingiberales): A Multiple Dataset Approach. Systematic Botany. 31(1): 89-106.

6.06

(1)Spreads vegetatively - see photo - new shoots spread across large areas suggesting ease of fragmentation (2)"Common near river bank" -- vegetative fragmentation by erosion on river bank

(1)http://www.gingersrus.com/images/Costaceae/Costus/dubius/Costus_dubius-SELBY-3597-01.jpg (2)http://www.gingersrus.com/DataSheet.php?PID=3597

6.07

1 to 2 years.

R. Baker. Lyon Arboretum. Pers. Comm.

7.01

Probably not - no evidence that the species is grown in heavy traffic areas.

7.02

The species has ornamental value and is available for purchase over the internet.

http://www.gingersrus.com/DataSheet.php?PID=3597

7.03

Probably not - No evidence that the species grows around seed crops.

http://www.gingersrus.com/DataSheet.php?PID=3597

7.04

No evidence that members of the Costus genus have any adaptations for wind dispersal.

Staples, W George and Derral H Herbst. 2005. A Tropical Garden Flora. Bishop Museum Press. Honolulu. Hawaii.

7.05

No evidence regarding seed dispersal.

7.06

No evidence regarding seed dispersal.

7.07

No evidence regarding seed dispersal.

7.08

No evidence regarding seed dispersal.

8.01

Produces copious seeds and spreads rapidly.[but don't know seed density]

http://www.botany.hawaii.edu/herbarium/digitallib/collections/hlaplants/pdf/Cot_Costus_dubius_w.pdf

8.02

No evidence regarding seed bank.

8.03

No evidence that the species is being controlled.

8.04

"We recently dug up/cut back/thinned out two large clumps of this Costus. This picture shows one of the clumps back in June 2006. It was much larger than this when we started. This picture shows the result about three weeks after we 'reduced' it. It seems to return from every piece of rhizome left in the soil − we did try to remove all of them!" [Costus species regrow quickly from rhizomes]

http://lagringasblogicito.blogspot.com/search/label/plants

8.05

Don’t know.