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

Asystasia gangetica (syn. A. coromandeliana Nees; Justicia gangetica L., Asystasia intrusa); Chinese violet

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

y

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

y

3.02

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

n=0

y

3.03

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

n=0

y

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

n

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

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

y

4.11

Climbing or smothering growth habit

y=1, n=0

y

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

y

6.07

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

See left

1

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

n

7.06

Propagules bird dispersed

y=1, n=-1

n

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

n

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

y

8.03

Well controlled by herbicides

y=-1, n=1

y

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

y

Total score:

12

Source

Notes

1.01

no evidence

1.02

McConnell, J.; Muniappan, R. (1991) Introduced ornamental plants that have become weeds on Guam. Micronesia, 1991, No.3, Supplement, pp.47-49, 4 ref.

AB: Introduced ornamental plants that are considered weeds on Guam include Antgonon leptopus, Spathodea campanulata, Coccinea grandis, Bauhinia monandra, Clerodendrum quadriloculare, Lantana camara, Ficus spp., Asystasia gangetica, Pilea microphylla, Wedelia trilobata, Mikania scandens and Mimosa pudica. Characteristics of ornamental plants that could become weeds on Guam include rapid growth/regrowth and prolific seed production.

1.03

Gorham, P.; Hosking, J. (2001) A form of Chinese violet: Asystasia gangetica subspecies micrantha . A form of Chinese violet: Asystasia gangetica subspecies micrantha , 2001, 2 pp.

AB: "A form of Chinese Violet, Asystasia gangetica subsp. micrantha , is a major weed that has begun to naturalize in Australia. The subspecies, which was initially recorded in New South Wales, Australia as naturalized at Boat Harbour, north of Newcastle, in July 1999, has been added to the list of prohibited imports, together with all A. gangetica subspecies. "

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/taxon.pl?411162 (24 July 2003)

Distributional range:
Native:
Africa: Angola; Botswana; Cameroon; Cote D'Ivoire; Equatorial Guinea; Ethiopia; Gambia; Ghana; Guinea; Guinea-Bissau - Cacheu; Kenya; Liberia; Malawi; Mali; Mozambique; Namibia; Nigeria; Senegal; Sierra Leone; South Africa; Swaziland; Tanzania; Togo; Uganda; Zaire; Zambia; Zimbabwe
Asia-Tropical: India; Sri Lanka
Other:  naturalized in Malesia, Australia, tropical America, & Oceania

2.02

2.03

http://www.hear.org/pier/asgan.htm

"Chinese violet grows in dry habitats between sea level and 300 m” (C.W. Smith, 1985). In Hawai'i, “cultivated and commonly becoming naturalized, primarily in urban areas or in low elevation, disturbed habitats” (Wagner et al., 1999). In Fiji, “cultivated or naturalized near settlements near sea level” (A.C. Smith, 1985). In Niue, “naturalised in some waste areas in and around the villages. In Alofi, one or two sloping banks near the radio station were almost carpeted with this plant. It was especially evident on ground that had fairly recently been cleared of scrub” (Sykes, 1970)."

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/taxon.pl?411162 (24 July 2003)

Distributional range:
Native:
Africa: Angola; Botswana; Cameroon; Cote D'Ivoire; Equatorial Guinea; Ethiopia; Gambia; Ghana; Guinea; Guinea-Bissau - Cacheu; Kenya; Liberia; Malawi; Mali; Mozambique; Namibia; Nigeria; Senegal; Sierra Leone; South Africa; Swaziland; Tanzania; Togo; Uganda; Zaire; Zambia; Zimbabwe
Asia-Tropical: India; Sri Lanka
Other:  naturalized in Malesia, Australia, tropical America, & Oceania

2.05

http://www.hear.org/pier/asgan.htm

"Chinese violet grows in dry habitats between sea level and 300 m” (C.W. Smith, 1985). In Hawai'i, “cultivated and commonly becoming naturalized, primarily in urban areas or in low elevation, disturbed habitats” (Wagner et al., 1999). In Fiji, “cultivated or naturalized near settlements near sea level” (A.C. Smith, 1985). In Niue, “naturalised in some waste areas in and around the villages. In Alofi, one or two sloping banks near the radio station were almost carpeted with this plant. It was especially evident on ground that had fairly recently been cleared of scrub” (Sykes, 1970)."

3.01

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/taxon.pl?411162 (24 July 2003)

naturalized in Malesia, Australia, tropical America, & Oceania

3.02

Whistler, A.W. (2000) Tropical Oramentals: a Guide. Timber Press, Inc., Portland, Oregon. 542pp. p.75

(1) "In some place, Hawaii, for example, it naturalized in disturbed forest communities."
(2) In Hawai'i, "cultivated and commonly becoming naturalized, primarily in urban areas or in low elevation, disturbed habitats" (Wagner et al., 1999). In Niue, naturalised in some waste areas in and around the villages. In Alofi, one or two sloping banks near the radio station were almost carpeted with this plant. It was especially evident on ground that had fairly recently been cleared of scrub"

3.03

(1) Ahmad Faiz, M. A. (2002) Efficacy of imazapyr and its mixtures against weeds under rubber. Journal of Rubber Research, 2002, Vol.5, No.1, pp.41-52, 19 ref.
(2) Chiu, S. B.; Chee, K. H. (1998) Survey and control of some weeds in West Kalimantan. Planter, 1998, Vol.74, No.869, pp.407-417, 7 ref.

(1) AB: "Trials were conducted along planting strips of rubber (Hevea brasiliensis ), between one- to six-year-old trees infested with weeds comprising mainly of Ottochloa nodosa , Paspalum conjugatum , Axonopus compressus , Borreria latifolia and Asystasia gangetica ."
(2) AB: A weed survey and sustained follow-up control were useful in preventing infestation by newly introduced weeds. In the Ngabang-Sanggau-Sintang-Nanga Pinoh region of West Kalimantan, Indonesia, Asystasia intrusa was not sighted, and the following five introduced weed species were found to be of limited distribution in oil palm and rubber estates: Pennisetum polystachion , Asystasia coromandeliana , Chromolaena odorata , Mimosa pigra and Mikania micrantha .

3.04

http://erin.gov.au/minister/env/2001/mr8may201.html

on the list of The Alert List for Environmental Weeds of Australia.
"The Alert List for Environmental Weeds is made up of 28 non-native weed species, which are identified as potentially damaging and are likely to be a significant threat to biodiversity" [this plant is a disturbance weed; no evidence of harm to native communities]

3.05

Mohamad, R. B. (1990) Country report: Malaysia. Weeds and weed management in Malaysia agriculture. BIOTROP Special Publication, 1990, No.38, pp.41-52, 37 ref.

AB: The impact of arable weeds in Malaysia is reviewed. The recent spread of Mimosa pigra, Asystasia intrusa, Pennisetum polystachion and Cuscuta australis is also reported.
[A. intrusa is a synonmym for A gangetics -- http://mobot.mobot.org/cgi-bin/search_vast ]

4.01

Whistler, A.W. (2000) Tropical Oramentals: a Guide. Timber Press, Inc., Portland, Oregon. 542pp. p.75

no descriptio of these traits

4.02

no evidence

4.03

no evidence

4.04

Chong, D. T.; Tajuddin, I.; Samat, A. M. S.; Stür, W. W.; Shelton, H. M. (1997) Stocking rate effects on sheep and forage productivity under rubber in Malaysia. Journal of Agricultural Science, 1997, Vol.128, No.3, pp.339-346, 7 ref.
(2) Dahlan, I.; Mahyuddin, M. D.; Yamada, Y.; Liang, J. B. (1988) Voluntary dry-matter intake of grazing cattle under oil palm plantation. Maximising livestock productivity. Proceedings of the 11th annual conference, Malaysian Society of Animal Production., 1988, pp.133-138, 11 ref.

(1) AB: "High stocking rates (>6 sheep/ha) resulted in a decrease in the proportion of palatable species (Pueraria phaseoloides, Paspalum conjugatum, Asystasia gangetica and Mikania micrantha ) "
(2) AB: "Animals selected species with high digestibility and grab samples comprised a daily av. of 59.2-65.8% of Asystasia coromandeliana, oil palm leaf, Ottochloa nodosa, Borreria laevicaulis, Paspalum conjugatum, Axonopus compressus, Mikania caudata, or Ageratum, Lygodium, Pueraria or Desmodium spp. "

4.05

Chong, D. T.; Tajuddin, I.; Samat, A. M. S.; Stür, W. W.; Shelton, H. M. (1997) Stocking rate effects on sheep and forage productivity under rubber in Malaysia. Journal of Agricultural Science, 1997, Vol.128, No.3, pp.339-346, 7 ref.

AB: "High stocking rates (>6 sheep/ha) resulted in a decrease in the proportion of palatable species (Pueraria phaseoloides, Paspalum conjugatum, Asystasia gangetica and Mikania micrantha ) "

4.06

Mateille, T.; Quénéhervé, P.; Hugon, R. (1994) The development of plant-parasitic nematode infestations on micro-propagated banana plants following field control measures in Côte d'Ivoire. Annals of Applied Biology, 1994, Vol.125, No.1, pp.147-159, 32 ref.

AB: "Of the weeds that were found in banana production areas, only Asystasia gangetica was parasitised by Radopholus similis; Helicotylenchus multicinctus and Hoplolaimus pararobustus were able to parasitize all weed species. "; "R. similis did not appear in the roots for 2 vegetative cycles. The other species, still present in the soil, invaded the roots and increased slowly in numbers."
[Radopholus similis invade A. gangetica and banana but not other weeds]

4.07

(1) Etuk, E. U. I.; Bassey, M. M.; Ekpenyong, D. C.; Ibiong, I. O. (1997) Quality assessment of two rural, infant dietary vegetables. Indian Journal of Nutrition and Dietetics, 1997, Vol.34, No.1, pp.5-9, 9 ref.
(2) Yeoh, H. H.; Wong, P. F. M. (1993) Food value of lesser utilised tropical plants. Food Chemistry, 1993, Vol.46, No.3, pp.239-241, 18 ref.

(1) AB: Portulaca oleracea and Asystasia gangetica are leafy vegetables used for infant dietary preparations. A gangetica did not have such high levels of minerals and vitamins but were high in protein and low in fibre, tannins and oxalates.
(2) AB: "Protein, amino acids and other nutritional and antinutritional factors were estimated in leaves of Asystasia gangetica , A. nemorum , Kaempferia galanga , Mentha arvensis and Piper sarmentosum which are eaten in Malaysia and Indonesia." [used as food]

4.08

Whistler, A.W. (2000) Tropical Oramentals: a Guide. Timber Press, Inc., Portland, Oregon. 542pp. p.75

"Relatively dry soil in sunny or partially shaded places are prefered. It can withstand drought and makes a good ground cover, especially on slopes that need protection from erosion."; "If established underneath a hedge it often comes up through the hedge by leaning it weak stems on the shrub's branches." [possibly yes, grow well in drought area, which may contribute to fuel load]

4.09

(1)Sahid, I. B.; Juraimi, A. S. (1998) Effects of water stress, shading and clipping on growth and development of Asystasia gangetica . Plant Protection Quarterly, 1998, Vol.13, No.3, pp.140-142, 7 ref. (2)http://gardening.worldonline.co.za/semishadetosun.htm

(1) "Greenhouse and field experiments were conducted to determine the effects of watering frequency (daily, and every 4 or 7 days), drought stress (no watering for 5-25 days), shade (0-82%) and clipping (after 4-12 weeks) on the growth and development of Asystasia gangetica ."; " Leaf area was not significantly affected with increasing shade levels. Shoot and root dry weight, and number of flowers and fruits, decreased with increasing shade."  [although yield decreased, it survived and flowered in shade] (2) Semi-shade

4.1

(1)Whistler, A.W. (2000) Tropical Oramentals: a Guide. Timber Press, Inc., Portland, Oregon. 542pp. (2)http://gardening.worldonline.co.za/0024.htm

(1)Relatively dry soils (2)Not fussy about soil

4.11

(1) Whistler, A.W. (2000) Tropical Oramentals: a Guide. Timber Press, Inc., Portland, Oregon. 542pp. p.75 (2) http://www.hear.org/pier/asgan.htm

(1) "herb to 1 m high". But "If established underneath a hedge it often comes up through the hedge by leaning its weak stems on the shrub's branches." (2) "Chinese violet is a rapidly growing perennial, shrubby herb which grows to 1 m height but can grow over shrubs up to 3 m tall. It can smother all vegetation in the herbaceous layer.

4.12

(1) Whistler, A.W. (2000) Tropical Oramentals: a Guide. Timber Press, Inc., Portland, Oregon. 542pp. p.75 (2) http://www.hear.org/pier/asgan.htm (2)http://www.botany.hawaii.edu/faculty/carr/asy_gan.htm

(1) "herb to 1 m high". But "If established underneath a hedge it often comes up through the hedge by leaning its weak stems on the shrub's branches." (2) "Chinese violet is a rapidly growing perennial, shrubby herb which grows to 1 m height but can grow over shrubs up to 3 m tall. It can smother all vegetation in the herbaceous layer. (2)Chinese violet grows in dry habitats between sea level and 300 m on all islands. There are dense infestations at Lualualei, 'Ewa Plains, Diamond Head, and Koko Head, O'ahu. [ground cover, not considered thickets] 

5.01

terrestrial

5.02

herb; Acanthaceae

5.03

no evidence

5.04

http://www.hear.org/pier/asgan.htm

"Propagation: Seed, rhizomes" [no obvious storage organ ]

6.01

no evidence

6.02

(1) Ismail, B. S.; Tasrif, A.; Sastroutomo, S. S.; Latiff, A. (1995) Weed seed populations in rubber and oil palm plantations with legume cover crops. Plant Protection Quarterly, 1995, Vol.10, No.1, pp.20-23, 16 ref.
(2) Whistler, A.W. (2000) Tropical Oramentals: a Guide. Timber Press, Inc., Portland, Oregon. 542pp. p.75

(1) AB: "The monthly emergence of A. gangetica , Ageratum conyzoides , Oldenlandia herbacea , Cyperus rotundus , P. conjugatum and C. rutidosperma are presented." [emergence from soil seed bank].
(2) "propagate by seed or cuttings"

6.03

no evidence

6.04

don't know

6.05

(1)Villalobos, E. M.; Shelly, T. E. (1996) Temporal and spatial variation in the foraging behavior of honey bees (Hymenoptera: Apidae) at Chinese violets. Florida Entomologist, 1996, Vol.79, No.3, pp.398-407 (2)http://gardening.worldonline.co.za/0024.htm

(1) "This study describes the foraging behaviour of honey bees (Apis mellifera ) on Chinese violet (Asystasia gangetica ) in Hawaii. Workers made 3 types of visits: 'out' (O ) visits involving nectar robbing through corollar slits made by carpenter bees (Xylocopa sonorina ), 'in-upright' (IR ) visits involving upright entry along the base of the corolla, and 'in-upside down' (ID ) visits involving spiral, upside-down entry along the top of the corolla. "
[visited by bees] (2) Attracts butterflies

6.06

http://www.agric.nsw.gov.au/reader/12893

roots at nodes and grows from pieces of roots

6.07

http://webs.lanset.com/pathline/plantratings1.htm

can be grown as an annual

7.01

http://www.hear.org/pier/asgan.htm

Habitat/ecology: In Hawai'i, cultivated and commonly becoming naturalized, primarily in urban areas or in low elevation, disturbed habitats” (Wagner et al., 1999). In Fiji, cultivated or naturalized near settlements near sea level (A.C. Smith, 1985). In Niue, naturalised in some waste areas in and around the villages. In Alofi, one or two sloping banks near the radio station were almost carpeted with this plant. It was especially evident on ground that had fairly recently been cleared of scrub” (Sykes, 1970). "long-distance dispersal is effected by man (C.W. Smith, 1985)."  [probably yes, appeared to grow near civilization]

7.02

McConnell, J.; Muniappan, R. (1991) Introduced ornamental plants that have become weeds on Guam. Micronesia, 1991, No.3, Supplement, pp.47-49, 4 ref.

AB: "Introduced ornamental plants"

7.03

[No direct evidence, but it was locally used as fodder and food. Seeds may disperse with plant materials, which may mix with other fodder species as well.]

7.04

http://www.hear.org/pier/asgan.htm

"The seeds are dispersed from explosive capsules but long-distance dispersal is effected by man "

7.05

http://www.hear.org/pier/asgan.htm

"The seeds are dispersed from explosive capsules but long-distance dispersal is effected by man "

7.06

http://www.hear.org/pier/asgan.htm

"The seeds are dispersed from explosive capsules but long-distance dispersal is effected by man "

7.07

http://www.hear.org/pier/asgan.htm

"The seeds are dispersed from explosive capsules but long-distance dispersal is effected by man "

7.08

no evidence of being ingested

8.01

(1) Whistler, A.W. (2000) Tropical Oramentals: a Guide. Timber Press, Inc., Portland, Oregon. 542pp.
(2) Wagner, W.L., D.R. Herbst and S.H. Sohmer. 1990. Manual of the flowing plants of Hawai‘i. Revised edition. University of Hawai‘i Press, Honolulu. 1853pp.

(1) p.76 "fruit a club shaped capsule 2-3 cm long"; (2) "Seeds four" [need 250 capsules per square meter, not common]

8.02

Ismail, B. S.; Tasrif, A.; Sastroutomo, S. S.; Latiff, A. (1995) Weed seed populations in rubber and oil palm plantations with legume cover crops. Plant Protection Quarterly, 1995, Vol.10, No.1, pp.20-23, 16 ref.

8.03

Ahmad Faiz, M. A. (2002) Efficacy of imazapyr and its mixtures against weeds under rubber. Journal of Rubber Research, 2002, Vol.5, No.1, pp.41-52, 19 ref.

AB: "Trials were conducted along planting strips of rubber (Hevea brasiliensis ), between one- to six-year-old trees infested with weeds comprising mainly of Ottochloa nodosa , Paspalum conjugatum , Axonopus compressus , Borreria latifolia and Asystasia gangetica ."; "Evaluation on efficacy of imazapyr showed weeds were susceptible at low rates of application and acceptable control could be obtained at 0.2 kg a.e./ha. Imazapyr at 0.375 kg a.e./ha provided more effective weed control than standard treatments with pre-mixed paraquat+diuron (0.6 kg a.i./ha+0.6 kg a.i./ha), pre-mixed glyphosate+dicamba (0.54 kg a.e./ha+0.27 kg a.e./ha), glufosinate ammonium (0.5 kg a.i./ha) and slashing."

8.04

Sahid, I. B.; Juraimi, A. S. (1998) Effects of water stress, shading and clipping on growth and development of Asystasia gangetica . Plant Protection Quarterly, 1998, Vol.13, No.3, pp.140-142, 7 ref. (2)http://www.botany.hawaii.edu/faculty/carr/asy_gan.htm

AB: "All plants showed regrowth after clipping. Shoot dry weight, and the number of flowers and fruits increased when clipping was carried out after 12 weeks, although flowering and fruiting were delayed. " (2)Although aerial portions may be killed by fire, the plant soon regenerates from basal shoots or seeds.

8.05

Rosley Abdullah (1985) Biological control of Asystasia by sheep grazing. Planters' Bulletin, Rubber Research Institute of Malaysia, 1985, No.183, pp.43-49

AB: "The sheep preferentially selected Asystasia spp. before passing on to other weeds such as Ottochloa and Mikania spp. Asystasia spp. had higher protein contents (24%) than other weeds; the benefits of sheep grazing as a means of controlling Asystasia spp. are discussed."
[grazing animals, goat, for example, may be effective natural enemies]