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

Indigofera suffruticosa; wild indigo, anil de pasto

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

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

3.05

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

n=0

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

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

4.08

Creates a fire hazard in natural ecosystems

y=1, n=0

y

4.09

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

y=1, n=0

n

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

n

4.12

Forms dense thickets

y=1, n=0

y

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

y

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

y

6.05

Requires specialist pollinators

y=-1, n=0

n

6.06

Reproduction by vegetative fragmentation

y=1, n=-1

n

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

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

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

y

8.01

Prolific seed production (>1000/m2)

y=1, n=-1

y

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

Total score:

11

Source

Notes

1.01

no evidence

1.02

John K. Francis, (Research Forester, International Institute of Tropical Forestry, U.S. Department of Agriculture, Forest Service, P.O. Box 25000, Río Piedras, PR 00928-5000.) Indigofera suffruticosa Mill. wild indigo. pdf document available at: <http://www.fs.fed.us/global/iitf/Indigofera%20suffruticosa.pdf>

Ecology.—In Hawaii, wild indigo has naturalized in dry, highly disturbed areas from near sea level to 1,160 m in elevation

1.03

no evidence

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?20058 (13 February 2003)

Distributional range:
Native:
Northern America: Mexico; United States - Florida, Louisiana, Mississippi, Texas
Southern America: Argentina [n.w.]; Belize; Bolivia; Brazil; Colombia; Costa Rica; Ecuador; El Salvador; Guatemala; Honduras; Nicaragua; Panama; Peru; Venezuela; West Indies
Other: naturalized elsewhere

2.02

2.03

(1)John K. Francis, (Research Forester, International Institute of Tropical Forestry, U.S. Department of Agriculture, Forest Service, P.O. Box 25000, Río Piedras, PR 00928-5000.) Indigofera suffruticosa Mill. wild indigo. pdf document available at: <http://www.fs.fed.us/global/iitf/Indigofera%20suffruticosa.pdf> (2)Adams, C.D. 1972. Flowering plants of Jamaica. University of the West Indies, Mona.

(1)"In Hawaii, wild indigo has naturalized in dry, highly disturbed areas from near sea level to 1,160 m in elevation (Pacific Island Ecosystems at Risk 2001). In Puerto Rico, the species grows from near sea level to about 700 m in elevation in areas that receive from about 750 to 1800 mm of precipitation annually." (2) Sea level to 4000 feet

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?20058 (13 February 2003)

Distributional range:
Native:
Northern America: Mexico; United States - Florida, Louisiana, Mississippi, Texas
Southern America: Argentina [n.w.]; Belize; Bolivia; Brazil; Colombia; Costa Rica; Ecuador; El Salvador; Guatemala; Honduras; Nicaragua; Panama; Peru; Venezuela; West Indies
Other: naturalized elsewhere

2.05

(1) Liu, C. X.; He, W. G. (1991) Leukogenic effect of complex indigo powder. Journal of Ethnopharmacology, 1991, Vol.34, No.1, pp.83-86, 4 ref.
(2) John K. Francis, (Research Forester, International Institute of Tropical Forestry, U.S. Department of Agriculture, Forest Service, P.O. Box 25000, Río Piedras, PR 00928-5000.) Indigofera suffruticosa Mill. wild indigo. pdf document available at: <http://www.fs.fed.us/global/iitf/Indigofera%20suffruticosa.pdf>

(1) China; (2) "The species has naturalized in Hawaii and is present in American Samoa, Guam, and a large number of the Pacific Island groups. Wild indigo has been introduced into tropical regions of the Old World."

3.01

John K. Francis, (Research Forester, International Institute of Tropical Forestry, U.S. Department of Agriculture, Forest Service, P.O. Box 25000, Río Piedras, PR 00928-5000.) Indigofera suffruticosa Mill. wild indigo. pdf document available at: <http://www.fs.fed.us/global/iitf/Indigofera%20suffruticosa.pdf>

Ecology.—In Hawaii, wild indigo has naturalized in dry, highly disturbed areas from near sea level to 1,160 m in elevation

3.02

John K. Francis, (Research Forester, International Institute of Tropical Forestry, U.S. Department of Agriculture, Forest Service, P.O. Box 25000, Río Piedras, PR 00928-5000.) Indigofera suffruticosa Mill. wild indigo. pdf document available at: <http://www.fs.fed.us/global/iitf/Indigofera%20suffruticosa.pdf>

"In Hawaii, wild indigo has naturalized in dry, highly disturbed areas." [no evidence that it is being controlled for in other than agricultural areas/overgrazed pastures]

3.03

(1)Bacon, P., P.J. Terry, N. Waltham, & P.Castro S. (1997) An Electronic Atlas of World Weed and Invasive Plants. Version 1.0, 1997. A database based on the original work "A Geographical Atlas of World Weeds" by Holm et al 1979. (2)http://www.fao.org/ag/AGP/AGPC/doc/Publicat/FAOBUL2/B201.htm (3)Notes from Jim Space on his survey of invasive plant species in Tonga. Available at: <http://www.issg.org/features/invasives_on_tonga.html>

(1)Listed as a common weed in Puerto Rico and Trinidad. (2)This weed is serious in some coastal areas of Efate. When it forms dense thickets pastures are severely shaded and thus weakened. Problem usually arises following prolonged over-stocking during the dry season and domination by this weed from the next wet season onwards.[VANUATU] (3)"At the request of the Kingdom of Tonga, Jim Space of the U.S. Forest Service's Pacific Island Ecosystems at Risk (PIER) project and Tim Flynn of the National Tropical Botanical Garden recently completed a survey of invasive plant species of environmental concern."; "Indigofera suffruticosa (indigo, local name 'akau veli) is a major component of the weed vegetation of Tonga, the worst seen in the Pacific so far."

3.04

no evidence

3.05

A Global Compendium of Weeds. Website available at: <http://www.hear.org/gcw/index.html>

Several Indigofera species were listed as "common" weed [Not prinicple or serious weeds; inadequate evidence that they are economic weeds]

4.01

John K. Francis, (Research Forester, International Institute of Tropical Forestry, U.S. Department of Agriculture, Forest Service, P.O. Box 25000, Río Piedras, PR 00928-5000.) Indigofera suffruticosa Mill. wild indigo. pdf document available at: <http://www.fs.fed.us/global/iitf/Indigofera%20suffruticosa.pdf>

no description of these traits

4.02

no evidence

4.03

no evidence

4.04

John K. Francis, (Research Forester, International Institute of Tropical Forestry, U.S. Department of Agriculture, Forest Service, P.O. Box 25000, Río Piedras, PR 00928-5000.) Indigofera suffruticosa Mill. wild indigo. pdf document available at: <http://www.fs.fed.us/global/iitf/Indigofera%20suffruticosa.pdf>

"Domestic and wild ruminant animals browse wild indigo plants."

4.05

Haemolytic anemia caused by Indigofera suffruticosa (Leg. Papilionoideae) in cattle.
FT: Anemia hemolítica causada por Indigofera suffruticosa (Leg. Papilionoideae) em bovinos.
AU: Barbosa Neto, J. D.; Oliveira, C. M. C.; Peixoto, P. V.; Barbosa, I. B. P.; Ávila, S. C.; Tokarnia, C. H.
AA: Central de Diagnóstico Veterinário (CEDIVET), Universidade Federal do Pará (UFPA), Castanhal, Pará 68740-080, Brazil.
SO: Pesquisa Veterinária Brasileira, 2001, Vol.21, No.1, pp.18-22, 6 ref.

AB: "The aerial parts of Indigofera suffruticosa Mill. (family Leg. Papilionoideae) were force-fed fresh to 6 cattle in daily doses of 10 to 40 g/kg. Cattle breeders of various parts of the Northeast of Brazil believe this plant is the cause of a non-fatal disease characterized by haemoglobinuria. " [results from force feeding are questionable evidence of poisoning in a natural situation]

4.06

Performance of Piezodorus guildinii on four species of Indigofera legumes.
AU: Panizzi, A. R.
AA: Centro Nacional de Pesquisa de Soja (CNPSo), Empresa Brasileira de Pesquisa Agropecuária (EMBRAPA), Caixa Postal 1061, 86001, Paraná, Brazil.
SO: Entomologia Experimentalis et Applicata, 1992, Vol.63, No.3, pp.221-228, 15 ref.

AB: "The performance of the pentatomid Piezodorus guildinii, a major pest of soyabean in South America, on 4 species of Indigofera was tested in the laboratory at 25 deg C, 65% RH and LD 14:10. Nymphal survival was 88, 15, 70 and 40% on I. endecaphylla, I. suffruticosa, I. hirsuta and I. truxillensis, resp. Field surveys conducted on I. truxillensis and I. suffruticosa, the 2 most abundant species in northern Paraná, indicated a greater number of nymphs, adults and egg masses on the former host. On both hosts, P. guildinii was more abundant during April-May, after soyabean harvest, suggesting movement of the populations from soyabean to Indigofera. " [A marginal host for this soybean pest (15% survival), other species are preferred]

4.07

no evidence

4.08

probably -- forms thickets and commonly grows in dry habitats, leaves not succulent, branches twiggy

4.09

John K. Francis, (Research Forester, International Institute of Tropical Forestry, U.S. Department of Agriculture, Forest Service, P.O. Box 25000, Río Piedras, PR 00928-5000.) Indigofera suffruticosa Mill. wild indigo. pdf document available at: <http://www.fs.fed.us/global/iitf/Indigofera%20suffruticosa.pdf>

"Wild indigo is not shade tolerant and will not grow under a closed forest stand."

4.1

John K. Francis, (Research Forester, International Institute of Tropical Forestry, U.S. Department of Agriculture, Forest Service, P.O. Box 25000, Río Piedras, PR 00928-5000.) Indigofera suffruticosa Mill. wild indigo. pdf document available at: <http://www.fs.fed.us/global/iitf/Indigofera%20suffruticosa.pdf>

"Soils derived from volcanic and sedimentary rocks in a wide range of soil textures are colonized."

4.11

John K. Francis, (Research Forester, International Institute of Tropical Forestry, U.S. Department of Agriculture, Forest Service, P.O. Box 25000, Río Piedras, PR 00928-5000.) Indigofera suffruticosa Mill. wild indigo. pdf document available at: <http://www.fs.fed.us/global/iitf/Indigofera%20suffruticosa.pdf>

"It is a short-lived shrub that reaches 1 to 2 m in height and 1 to 2 cm in stem diameter."

4.12

http://www.fao.org/ag/AGP/AGPC/doc/Publicat/FAOBUL2/B201.htm

Thickets should be slashed to 30 - 40 cm height and young regrowth sprayed with Grazon DS as recommended

5.01

terrestrial

5.02

shrub; fabaceae

5.03

AB: " Indigofera suffruticosa behaved as intermediate N2-fixers (RAU 30-59%)."

5.04

shrub

6.01

no evidence

6.02

John K. Francis, (Research Forester, International Institute of Tropical Forestry, U.S. Department of Agriculture, Forest Service, P.O. Box 25000, Río Piedras, PR 00928-5000.) Indigofera suffruticosa Mill. wild indigo. pdf document available at: <http://www.fs.fed.us/global/iitf/Indigofera%20suffruticosa.pdf>

"17 percent germinated in 7 to 24 days after sowing. Seed from a Mexican collection gave more than 90 percent germination (in the field) when a mechanical scarification was used and nearly 100 percent when wet-dry cycles were combined with scarification"

6.03

no evidence

6.04

http://www.nativeseeds.org/v1/cat.php?catID=26

A self-pollinating legume,

6.05

typical pea flower (bees)

6.06

no evidence

6.07

http://tomclothier.hort.net/page06.html

can grow as an annual

7.01

no evidence

7.02

John K. Francis, (Research Forester, International Institute of Tropical Forestry, U.S. Department of Agriculture, Forest Service, P.O. Box 25000, Río Piedras, PR 00928-5000.) Indigofera suffruticosa Mill. wild indigo. pdf document available at: <http://www.fs.fed.us/global/iitf/Indigofera%20suffruticosa.pdf>

"In Hawaii, 20,400 kg of wild indigo can be produced per hectare from which 227 kg of indigo paste can be separated." [grown for dye production]

7.03

no evidence

7.04

John K. Francis, (Research Forester, International Institute of Tropical Forestry, U.S. Department of Agriculture, Forest Service, P.O. Box 25000, Río Piedras, PR 00928-5000.) Indigofera suffruticosa Mill. wild indigo. pdf document available at: <http://www.fs.fed.us/global/iitf/Indigofera%20suffruticosa.pdf>

"The pods remain open on the branches, exposing but not expelling the seeds. Mechanisms of transport have not been reported."

7.05

no evidence

7.06

no evidence

7.07

no evidence

7.08

Moreno-Casasola, P.; Grime, J. P.; Martínez, M. L. (1994) A comparative study of the effects of fluctuations in temperature and moisture supply on hard coat dormancy in seeds of coastal tropical legumes in Mexico. Journal of Tropical Ecology, 1994, Vol.10, No.1, pp.67-86, 29 ref.

legume with hard seed

8.01

John K. Francis, (Research Forester, International Institute of Tropical Forestry, U.S. Department of Agriculture, Forest Service, P.O. Box 25000, Río Piedras, PR 00928-5000.) Indigofera suffruticosa Mill. wild indigo. pdf document available at: <http://www.fs.fed.us/global/iitf/Indigofera%20suffruticosa.pdf>

"The curved legumes are short (1.1 to 2.5 cm) and contain three to seven seeds that are 1.5 mm wide and 1 mm thick"; "These seeds averaged 0.0039 g/seed or about 257,000 seeds/kg. " [small seeds with about 250 seeds per gram.]

8.02

Moreno-Casasola, P.; Grime, J. P.; Martínez, M. L. (1994) A comparative study of the effects of fluctuations in temperature and moisture supply on hard coat dormancy in seeds of coastal tropical legumes in Mexico. Journal of Tropical Ecology, 1994, Vol.10, No.1, pp.67-86, 29 ref.

AB: "The effect of fluctuations in temperature and moisture supply on hard seeds of nine tropical coastal sand dune legumes. Germination percentage increased considerably in most species as a consequence of treatment, with marked effects occurring at temperature fluctuations greater than 20 deg C and becoming detectable after 45 days. In several species the effect of applying wetting and drying cycles was to lower the amplitude of temperature fluctuation necessary to soften the seeds."

8.03

http://www.fao.org/ag/AGP/AGPC/doc/Publicat/FAOBUL2/B201.htm

Thickets should be slashed to 30 - 40 cm height and young regrowth sprayed with Grazon DS as recommended.

8.04

John K. Francis, (Research Forester, International Institute of Tropical Forestry, U.S. Department of Agriculture, Forest Service, P.O. Box 25000, Río Piedras, PR 00928-5000.) Indigofera suffruticosa Mill. wild indigo. pdf document available at: <http://www.fs.fed.us/global/iitf/Indigofera%20suffruticosa.pdf>

"The shrub may have multiple stems, especially if it has been disturbed by grazing or fire."

8.05

no evidence