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

Mucuna pruriens (Stizolobium pruriens); velvet bean, cowitch

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

y

4.01

Produces spines, thorns or burrs

y=1, n=0

n

4.02

Allelopathic

y=1, n=0

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

n

4.07

Causes allergies or is otherwise toxic to humans

y=1, n=0

y

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

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

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

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

n

8.05

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

y=-1, n=1

Total score:

7

Source

Notes

1.01

no evidence

1.02

USDA, Institute of Pacific Islands Forestry (2001) Pacific Island Ecosystems at Risk (PIER) webpage <http://www.hear.org/pier/mupru.htm>

A weed species in Mexico, Mozambique, Jamaica and Madagascar.

1.03

http://216.239.51.100/search?q=cache:LbR1EG3fuIcJ:www.nt.gov.au
/dbird/dpif/pubcat/agnotes/weeds/652.pdf+cow+itch+seeds&hl=en&ie=UTF-8

Numerous cultivars are in use, but no indication of specific race being weedy. [A cultivated variety of the same species, Mucuna pruriensvar. utilis, occurs in Queensland. Thisvariety is commonly known as velvet bean and is used as a fast growing, leguminous, greenmanure crop. It does not have severe irritating hairs like cow itch, but haemorrhage and deathcan result from cattle eating the hairy pods.]

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?24652 (18 February 2003)

Native distribution:
Africa: Angola; Burundi; Cameroon; Central African Republic; Chad; Equatorial Guinea; Ethiopia; Ghana; Guinea; Guinea-Bissau; Kenya; Liberia; Madagascar; Malawi; Nigeria; Sao Tome and Principe; Senegal; Sierra Leone; Somalia; South Africa - Natal, Transvaal; Sudan; Tanzania; Togo; Uganda; Zaire; Zambia; Zimbabwe
Asia-Tropical: Bangladesh; Bhutan; Cambodia; India - Jammu and Kashmir; Indonesia; Malaysia; Myanmar; Nepal; Papua New Guinea; Philippines; Sri Lanka; Thailand; Vietnam
Other: widely cult. & naturalized

2.02

2.03

(1)Grassland Index. (The basic information in this index has been taken from two FAO publications "Tropical Grasses" (1990) by Skerman, P.J. and F. Riveros and "Tropical Forage Legumes" (1988) by Skerman, P.J., Cameron, D.G. and F. Riveros.). Available at: <http://www.fao.org/ag/AGP/AGPC/doc/Gbase/Default.htm> (2)http://www.hear.org/pier/mupru.htm (3)http://pppis.fao.org/

(1)"They grow from sea level to 2 100 m in Kenya, apparently the altitude limit. Rainfall range of the species is from 650 to 2 500 mm." (2)“cultivated and sometimes sparingly naturalized at low elevations up to about 200 m” (Smith, 1985). (3)tropical wet & dry (Aw), tropical wet (Ar), steppe or semiarid (Bs), subtropical humid (Cf), subtropical dry summer (Cs), subtropical dry winter (Cw), Young plants may not tolerate 5°C

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?24652 (18 February 2003)

Native distribution:
Africa: Angola; Burundi; Cameroon; Central African Republic; Chad; Equatorial Guinea; Ethiopia; Ghana; Guinea; Guinea-Bissau; Kenya; Liberia; Madagascar; Malawi; Nigeria; Sao Tome and Principe; Senegal; Sierra Leone; Somalia; South Africa - Natal, Transvaal; Sudan; Tanzania; Togo; Uganda; Zaire; Zambia; Zimbabwe
Asia-Tropical: Bangladesh; Bhutan; Cambodia; India - Jammu and Kashmir; Indonesia; Malaysia; Myanmar; Nepal; Papua New Guinea; Philippines; Sri Lanka; Thailand; Vietnam
Other: widely cult. & naturalized

2.05

USDA, Institute of Pacific Islands Forestry (2001) Pacific Island Ecosystems at Risk (PIER) webpage <http://www.hear.org/pier/mupru.htm>

A weed species in Mexico, Jamaica and Madagascar.

3.01

USDA, Institute of Pacific Islands Forestry (2001) Pacific Island Ecosystems at Risk (PIER) webpage <http://www.hear.org/pier/mupru.htm>

A weed species in Mexico, Mozambique, Jamaica and Madagascar.

3.02

[answered yes for AG weed, so left blank for disturbance weed; no evidence of being a garden or amenity weed]

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://216.239.51.100/search?q=cache:LbR1EG3fuIcJ:www.nt.gov.au
/dbird/dpif/pubcat/agnotes/weeds/652.pdf+cow+itch+seeds&hl=en&ie=UTF-8(3)http://www.silsoe.cranfield.ac.uk/iwe/fai/weed_suppressing_technology/weeds.htm

Listed as a serious species in Mexico, Mozambique, and principal weed in Jamaica and Madagascar. (2)It is also a weed in crops, scrambling over other vegetation. Hand harvesting in infested crops is difficult due to the irritating hairs. (3)Mucuna pruriens was rejected by some farmers in the Ichilo-Sara area of Bolivia, because it dominated Bactris gasipaes, a local palm, and banana, limiting their growth and development.

3.04

USDA, Institute of Pacific Islands Forestry (2001) Pacific Island Ecosystems at Risk (PIER) webpage <http://www.hear.org/pier/mupru.htm>

Picture of "Mucuna pruriens impacting native forest on Saipan". No information on extent of problem, limitation to roadsides, etc.

3.05

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.

M. coriacea was listed as a principal weed in Mozambique

4.01

USDA, Institute of Pacific Islands Forestry (2001) Pacific Island Ecosystems at Risk (PIER) webpage <http://www.hear.org/pier/mupru.htm>

"The pods are covered with reddish-orange hairs that are readily dislodged and can cause intense irritation to the skin " [Hair - not spines, thors or burrs]

4.02

Fujii, Y.; Shibuya, T.; Yasuda, T. (1992) Allelopathy of velvetbean: its discrimination and identification of L-DOPA as a candidate of allelopathic substances. JARQ, Japan Agricultural Research Quarterly, 1992, Vol.25, No.4, pp.238-247, 34 ref.

AB: Laboratory bioassays and field experiments on 70 species indicated Mucuna pruriens var. utilis was the most promising allelopathic plant. HPLC, germination bioassays and seedling growth tests identified the allelopathin as L-3,4-dihydroxyphenylalanine (L-DOPA), present at about 1% by FW in leaves and roots of M. pruriens. L-DOPA suppressed growth of some broadleaf weeds but had little effect on grasses. [field evidence?]

4.03

no evidence

4.04

(1)Grassland Index. (The basic information in this index has been taken from two FAO publications "Tropical Grasses" (1990) by Skerman, P.J. and F. Riveros and "Tropical Forage Legumes" (1988) by Skerman, P.J., Cameron, D.G. and F. Riveros.). Available at: <http://www.fao.org/ag/AGP/AGPC/doc/Gbase/Default.htm> (2)http://pppis.fao.org/

(1)"When grazing the crop, the animals are turned in"; but "Krause (1911) stated that velvet bean was the least palatable of the forage legumes he had tested. " [accepted but not prefered; more often used as silage mixed with other forage for higher protein content] (2) It is primarely used in animal feeds and young pods and seeds are eaten as vegetables.

4.05

Grassland Index. (The basic information in this index has been taken from two FAO publications "Tropical Grasses" (1990) by Skerman, P.J. and F. Riveros and "Tropical Forage Legumes" (1988) by Skerman, P.J., Cameron, D.G. and F. Riveros.). Available at: <http://www.fao.org/ag/AGP/AGPC/doc/Gbase/Default.htm>

used as silage mixed with other forage

4.06

Dhingra, O. D.; Netto, R. A. C. (2001) Reservoir and non-reservoir hosts of bean-wilt pathogen, Fusarium oxysporum f. sp. phaseoli . Journal of Phytopathology, 2001, Vol.149, No.7/8, pp.463-467, 26 ref.

AB: "The capacity of F. oxysporum f.sp. phaseoli to multiply in the roots of 12 non-host plant species was determined with the objective of selecting potential candidates for crop rotation and/or green manuring in infested bean (Phaseolus vulgaris ) fields. The roots and lower stem of Dolichos lablab [Lablab purpureus ], P. lunatus , Mucuna aterrima , Canavalia ensiforme and Vigna unguiculata were the most compatible with the pathogen. No disease symptoms developed on any plant species. Most plant species recommended for green manuring in bean fields allowed extensive root and stem colonization by F. oxysporum f.sp. phaseoli and were considered as reservoir hosts. " [Mucuna pruriens not mentioned here, this Fusarium seems capable of infecting many bean species]

4.07

USDA, Institute of Pacific Islands Forestry (2001) Pacific Island Ecosystems at Risk (PIER) webpage <http://www.hear.org/pier/mupru.htm> (2)http://216.239.51.100/search?q=cache:LbR1EG3fuIcJ:www.nt.gov.au
/dbird/dpif/pubcat/agnotes/weeds/652.pdf+cow+itch+seeds&hl=en&ie=UTF-8

no evidence ["The pods are covered with reddish-orange hairs that are readily dislodged and can cause intense irritation to the skin "] (2)The most undesirable feature of cow itch is the dense orange coloured hairs on the pods whichcause severe irritation to the skin. The hairs dislodge easily and can drop onto the neck andarms, getting under clothing and causing intense discomfort. This gives the plant its Englishcommon name "cow itch", and its South American common name "pica-pica" meaning "itchy-itchy

4.08

Galiba, M.; Vissoh, P.; Dagbénonbakin, G.; Fagbohoun, F. (2000) The reactions and fears of farmers utilizing velvet bean (Mucuna pruriens ).[FT: Réactions et craintes des paysans liées à l'utilisation du pois mascate (Mucuna pruriens var. utilis ] in Cover crops in West Africa: contributing to sustainable agriculture, 1-3 October 1996, Cotonou, Benin., 1998, pp.55-64, 12 ref. Editors: Buckles, D.; Etèka, A.; Osiname, O.; Galiba, M.; Galiano, G.

AB: "Mucuna is generally planted as a sole crop in the north and in association with maize in the south, where land pressure is greater. The constraints to adoption of Mucuna are centred around its use for both human and animal consumption; farmers' difficulties in respecting the optimum planting dates for biomass production; the risk of loss due to bush fires and animals in the dry season." [sensitive to fire in agricultural system]

4.09

(1)Lee, D. W. (1988) Simulating forest shade to study the developmental ecology of tropical plants: juvenile growth in three vines in India. Journal of Tropical Ecology, 1988, Vol.4, No.3, pp.281-292, 32 ref. (2)http://pppis.fao.org/

(1)"The tropical leguminous vines Abrus precatorius, Caesalpinia bundicela [C. bonducella] and Mucuna pruriens were grown in a shadehouse." (2) Light tolerance: clear bright skies to cloudy skies.

4.1

Grassland Index. (The basic information in this index has been taken from two FAO publications "Tropical Grasses" (1990) by Skerman, P.J. and F. Riveros and "Tropical Forage Legumes" (1988) by Skerman, P.J., Cameron, D.G. and F. Riveros.). Available at: <http://www.fao.org/ag/AGP/AGPC/doc/Gbase/Default.htm>

" Tolerates a wide range of soils, from sands to clays, and will grow on soils of appreciable acidity. "

4.11

Grassland Index. (The basic information in this index has been taken from two FAO publications "Tropical Grasses" (1990) by Skerman, P.J. and F. Riveros and "Tropical Forage Legumes" (1988) by Skerman, P.J., Cameron, D.G. and F. Riveros.). Available at: <http://www.fao.org/ag/AGP/AGPC/doc/Gbase/Default.htm>

"Vigorously growing, trailing vine (grown mostly for green manuring or temporary pasture), slender, slightly ridged, and extending over 6 m in length (grown on supports, they may grow to over 10 m). "

4.12

slender vine

5.01

terrestrial

5.02

annual vine; fabaceae

5.03

annual vine [not woody]

5.04

annual vine

6.01

no evidence

6.02

Silva, T. R. B. da (2001) Overcoming velvet bean seed dormancy by friction with sand. [FT: Superação da dormência de sementes de mucunapreta através de atrito com areia.] Revista de Agricultura (Piracicaba), 2001, Vol.76, No.3, pp.469-475, 13 ref.

AB: "The greatest germination (91 and 93%) and lowest seed mortality (9 and 7%) were obtained with 20 and 25 min friction"

6.03

no evidence

6.04

Lubis, S. H. A.; Sastrapradja, S.; Lubis, I.; Sastrapradja, D. (1977) Genetic variation of Mucuna pruriens (L.) DC. 1. Floral biology and pollination mechanism. Annales Bogorienses, 1977, Vol.6, No.3, pp.133-141, 8 ref.

The flower is cleistogamous. [Cleistogamous – having flowers that can self-pollinated and set seed without fully opening]

6.05

Lubis, S. H. A.; Sastrapradja, S.; Lubis, I.; Sastrapradja, D. (1977) Genetic variation of Mucuna pruriens (L.) DC. 1. Floral biology and pollination mechanism. Annales Bogorienses, 1977, Vol.6, No.3, pp.133-141, 8 ref.

The flower is cleistogamous. [Cleistogamous – having flowers that can self-pollinated and set seed without fully opening (eg. Utricularia subulata).]

6.06

no evidence

6.07

Grassland Index. (The basic information in this index has been taken from two FAO publications "Tropical Grasses" (1990) by Skerman, P.J. and F. Riveros and "Tropical Forage Legumes" (1988) by Skerman, P.J., Cameron, D.G. and F. Riveros.). Available at: <http://www.fao.org/ag/AGP/AGPC/doc/Gbase/Default.htm>

"When grazing the crop, the animals are turned in after the pods are mature, some 170 to 220 days in Hawaii"

7.01

no evidence [large seed]

7.02

Grassland Index. (The basic information in this index has been taken from two FAO publications "Tropical Grasses" (1990) by Skerman, P.J. and F. Riveros and "Tropical Forage Legumes" (1988) by Skerman, P.J., Cameron, D.G. and F. Riveros.). Available at: <http://www.fao.org/ag/AGP/AGPC/doc/Gbase/Default.htm>

"The crop is usually grown alone for green manure and for silage"

7.03

no evidence

7.04

Grassland Index. (The basic information in this index has been taken from two FAO publications "Tropical Grasses" (1990) by Skerman, P.J. and F. Riveros and "Tropical Forage Legumes" (1988) by Skerman, P.J., Cameron, D.G. and F. Riveros.). Available at: <http://www.fao.org/ag/AGP/AGPC/doc/Gbase/Default.htm>

Pods, 10 to 14 in a duster, are borne singly, 10 to 12.5 cm long, curved, with a greyish-white pubescence of short, silky hairs . Seeds are black (Mauritius bean) and glossy when mature, 1.2 to 1.5 cm long and 0.9 to 1.1 cm broad with raised white hilum half as long as the seed. Each pod contains three to five seeds . [big seed]

7.05

no evidence

7.06

no evidence

7.07

no evidence

7.08

large seed; no evidence of consumption

8.01

Grassland Index. (The basic information in this index has been taken from two FAO publications "Tropical Grasses" (1990) by Skerman, P.J. and F. Riveros and "Tropical Forage Legumes" (1988) by Skerman, P.J., Cameron, D.G. and F. Riveros.). Available at: <http://www.fao.org/ag/AGP/AGPC/doc/Gbase/Default.htm>

About 1000 seeds weigh 1 kg; 3.85 tonnes seed per hectare in Hawaii with a variety named Lyon. [1000x3850/10000 = 385 seed per square meter]

8.02

1)Silva, T. R. B. da (2001) Overcoming velvet bean seed dormancy by friction with sand. [FT: Superação da dormência de sementes de mucunapreta através de atrito com areia.] Revista de Agricultura (Piracicaba), 2001, Vol.76, No.3, pp.469-475, 13 ref. (2)http://216.239.51.100/search?q=cache:LbR1EG3fuIcJ:www.nt.gov.au
/dbird/dpif/pubcat/agnotes/weeds/652.pdf+cow+itch+seeds&hl=en&ie=UTF-8 (3)http://edis.ifas.ufl.edu/WG209

AB: The use of sand friction for overcoming the dormancy of seeds of Mucuna aterrima was evaluated. The following treatments were used: escarification with sandpaper; 5, 10, 15, 20 and 25 min friction with sand. The greatest germination (91 and 93%) and lowest seed mortality (9 and 7%) were obtained with 20 and 25 min friction, respectively.
(2) "cow itch is likely tohave dormant seeds which will ensure that any control must be followed up" (3)It is important to continue pulling seedlings until seed bank is exhausted.

8.03

(1)http://216.239.51.100/search?q=cache:LbR1EG3fuIcJ:www.nt.gov.au
/dbird/dpif/pubcat/agnotes/weeds/652.pdf+cow+itch+seeds&hl=en&ie=UTF-8 (2)http://edis.ifas.ufl.edu/WG209

(1)"Control of cow itch should not be too difficult if infestations are found early. Being a legume it isprobably susceptible to a range of herbicides" (2)Basal bark application of 10% Garlon 4

8.04

http://edis.ifas.ufl.edu/WG209

does not resprout from roots.

8.05

no evidence