Medicago polymorpha L., Fabaceae

Click on an image for links to BIGGER PICTURES

Present on Pacific Islands?  yes

Primarily a threat at high elevations?  no

Risk assessment results:  Reject, score: 11 (Go to the risk assessment).

Common name(s): [more details]

English: bur clover, burr medic, California bur-clover, hairy medic, toothed bur-clover, toothed medic

French: luzerne hérissée

Spanish: carretón de amores, trébol de carretilla, trefol de carretilla

Habit:  herb

Description:  "Annual herbs; stems prostrate, up to 4 dm long, branched, subglabrous, with a few long hairs on petiolules, lower surface of leaflets, and calyx.  Leaflets obovate-cuneate, 7-25 mm long, 5-23 mm wide, glabrate, margins dentate in upper half, apex rounded to truncate or emarginate, stipules narrowly elliptic to narrowly ovate, laciniate.  Flowers (1-) 3-5 (-8) in racemes; corolla yellow, 3-4.5 mm long.  Pods 4-8 (-10) mm in diameter, spirally twisted in (1.5-) 3-4 (-6) turns, glabrous or subglabrous, transverse veins prominent, anastomosing, groove between submarginal and marginal vein wide, with nearly straight prickles 2-3 mm long, arising from the submarginal and marginal veins.  Seeds several"  (Wagner et al., 1999; pp. 684, 1878).

Habitat/ecology:  In Hawai‘i, "naturalized in open, dry to occasionally mesic, disturbed areas such as pastures, roadsides and vacant lots, 0-1,220 m" (Wagner et al., 1999; p. 684).  In Tonga, "uncommon in waste places" (Whistler, 1988; p. 28). In New Caledonia, "peu commun et vu surtout comme mauvaise herbe des gazons" (MacKee, 1994; p. 86).

Propagation:  Seed

Native range:  "Europe and temperate Asia to china and Japan, also in northern India, widely cultivated as a fodder plant" (Wagner et al., 1999; p. 684).

Presence:

Pacific
Country/Terr./St. & Island group	Location	Cited status & Cited as invasive & Cited as cultivated & Cited as aboriginal introduction?	Reference & Comments
Australia (Pacific offshore islands) Lord Howe Island	Lord Howe Island	introduced	Pickard, J. (1984) (p. 206) var. vulgaris
Australia (Pacific offshore islands) Lord Howe Island	Lord Howe Island	introduced invasive	Orchard, Anthony E., ed. (1994) (p. 19) Vouchers cited: G. Uhe 1306 (K); L.A.S. Johnson & A.N. Rodd 1209 (K, NSW); J. Pickard 2660 (NSW); 1898, J.H. Maiden (NSW)
Australia (Pacific offshore islands) Norfolk Islands	Norfolk Island	introduced invasive	Orchard, Anthony E., ed. (1994) (p. 9) Vouchers cited: G. Uhe 1145 (K); 1898 & 1902, I. Robinson (NSW)
Chile (offshore islands) Juan Fernández Islands	Isla Más a Tierra (Robinson Crusoe Island)	introduced invasive	Atkinson, Rachel/Sawyer, John (2011)
Chile (offshore islands) Juan Fernández Islands	Isla Más a Tierra (Robinson Crusoe Island)	introduced invasive	Danton, Philippe/Perrier, Christophe/Martinez Reyes, Guido (2006) (p. 555)
Chile (offshore islands) Juan Fernández Islands	Isla Más Afuera (Alejandro Selkirk Island)	introduced invasive	Atkinson, Rachel/Sawyer, John (2011)
Chile (offshore islands) Juan Fernández Islands	Isla Más Afuera (Alejandro Selkirk Island)	introduced invasive	Danton, Philippe/Perrier, Christophe/Martinez Reyes, Guido (2006) (p. 555)
Chile (offshore islands) Juan Fernández Islands	Isla Santa Clara	introduced invasive	Atkinson, Rachel/Sawyer, John (2011)
Chile (offshore islands) Juan Fernández Islands	Isla Santa Clara	introduced invasive	Danton, Philippe/Perrier, Christophe/Martinez Reyes, Guido (2006) (p. 555)
Guam Guam Island	Guam Island	introduced	Stone, Benjamin C. (1970) (p. 337) var. vulgaris. Recent presence not confirmed.
Guam Guam Island	Guam Island	introduced	Fosberg, F. R./Sachet, Marie-Hélène/Oliver, Royce (1979) (p. 114) var. vulgaris per Stone. Recent presence not confirmed.
State of Hawaii Hawaiian Islands	Hawai‘i (Big) Island	introduced invasive cultivated	Wagner, Warren L./Herbst, Derral R./Sohmer, S. H. (1999) (p. 684) Voucher cited: Rock 3199 (BISH)
State of Hawaii Hawaiian Islands	Kaua‘i Island	introduced invasive cultivated	Wagner, Warren L./Herbst, Derral R./Sohmer, S. H. (1999) (p. 684)
State of Hawaii Hawaiian Islands	Kure Atoll	introduced	Starr, Forest/Martz, Kim/Loope, Lloyd (2001) (p. 14) Previously reported, not observed in this survey.
State of Hawaii Hawaiian Islands	Lāna‘i Island	introduced invasive cultivated	Wagner, Warren L./Herbst, Derral R./Sohmer, S. H. (1999) (p. 684)
State of Hawaii Hawaiian Islands	Maui Island	introduced invasive cultivated	Wagner, Warren L./Herbst, Derral R./Sohmer, S. H. (1999) (p. 684)
State of Hawaii Hawaiian Islands	Moloka‘i Island	introduced invasive	Herbst, Derral R./Wagner, Warren L. (1996) (p. 14) Voucher cited: Degener 3514 (US)
State of Hawaii Hawaiian Islands	O‘ahu Island	introduced invasive cultivated	Wagner, Warren L./Herbst, Derral R./Sohmer, S. H. (1999) (p. 684) Voucher cited: Forbes s. n. (BISH)
Japan (offshore islands) Bonin (Ogasawara) Islands	Bonin (Ogasawara) Islands	introduced	Kato, Hidetoshi (2007) Also var. confinis (W.D.J.Koch) Ooststr. et Reichg.
New Caledonia New Caledonia Archipelago	Île Grande Terre	introduced invasive	Tassin, Jacques (2005)
New Caledonia New Caledonia Archipelago	Île Grande Terre	introduced invasive	MacKee, H. S. (1994) (p. 86) Vouchers cited: Pancher s.n., MacKee 5195, Déméné in MacKee 14642, MacKee 37330
New Zealand (offshore islands) Kermadec Islands	Raoul Island	introduced invasive	Sykes, W. R. (1977) (p. 125)
Tonga Tonga Islands	Tonga Islands		Whistler, W. A. (1988) (p. 26)
United States (other Pacific offshore islands) Midway Atoll	Midway Atoll	introduced invasive	Bruegmann, Marie M. (1999) (p. 2) Voucher cited: Bruegmann 2013 (BISH)

Pacific Rim
Country/Terr./St. & Island group	Location	Cited status & Cited as invasive & Cited as cultivated & Cited as aboriginal introduction?	Reference & Comments
Australia Australia (continental)	Australia (continental)		Holm, Leroy/Pancho, Juan V./Herberger, James P./Plucknett, Donald L. (1979) (p. 231)
China China	Hong Kong	introduced cultivated	Wu, Te-lin (2001) (p. 149)
Japan Japan	Japan (country)	introduced	Mito, Toshikazu/Uesugi, Tetsuro (2004) (p. 185) var. polymorpha, var. confinis (W.D.J. Koch), var. lapponica Burnet and var. microdon (Ehr.)

Additional information:
Additional online information about Medicago polymorpha is available from the Hawaiian Ecosystems at Risk project (HEAR).

Information about Medicago polymorpha as a weed (worldwide references) may be available from the Global Compendium of Weeds (GCW).

Taxonomic information about Medicago polymorpha may be available from the Germplasm Resources Information Network (GRIN).

References:

Atkinson, Rachel/Sawyer, John. 2011. Naturalized species in the Juan Fernández Archipelago, Chile. Unpublished spreadsheet.

Bruegmann, Marie M. 1999. New records of flowering plants on Midway Atoll. In: Evenhuis, Neal L. and Eldredge, Lucius G., eds. Records of the Hawaii Biological Survey for 1998. Part 2: Notes. Bishop Museum Occasional Papers. 59:1-2.

Danton, Philippe/Perrier, Christophe/Martinez Reyes, Guido. 2006. Nouveau catalogue de la flore vaculaire de l'archipel Juan Fernández (Chile) [Nuevo catálogo de la flora vacular del Archipélago Juan Fernández (Chile)]. Acta Bot. Gallica 153(4):399-587.

Fosberg, F. R./Sachet, Marie-Hélène/Oliver, Royce. 1979. A geographical checklist of the Micronesian dicotyledonae. Micronesica 15:1-295.

Herbst, Derral R./Wagner, Warren L. 1996. Contributions to the Flora of Hawai‘i. V. In: Evenhuis, Neal L. and Miller, Scott, E., eds. Records of the Hawaii Biological Survey for 1995. Part 2: Notes. Bishop Museum Occasional Papers. 46:8-12.

Holm, Leroy/Pancho, Juan V./Herberger, James P./Plucknett, Donald L. 1979. A geographical atlas of world weeds. John Wiley & Sons, New York. 391 pp.

Kato, Hidetoshi. 2007. Herbarium records of Makino Herbarium, Tokyo Metropolitan University. Personal communication.

MacKee, H. S. 1994. Catalogue des plantes introduites et cultivées en Nouvelle-Calédonie. Muséum National d'Histoire Naturelle, Paris, 164 p.

Mito, Toshikazu/Uesugi, Tetsuro. 2004. Invasive alien species in Japan: the status quo and the new regulation for prevention of their adverse effects. Global Environmental Research 8(2)/2004: 171-191.

Orchard, Anthony E., ed. 1994. Flora of Australia. Vol. 49, Oceanic islands 1. Australian Government Publishing Service, Canberra.

Pickard, J. 1984. Exotic plants on Lord Howe Island: Distribution in space and time, 1853-1981. J. of Biogeography 11:181-208.

Starr, Forest/Martz, Kim/Loope, Lloyd. 2001. Botanical inventory of Kure Atoll. United States Geological Survey, Biological Resources Division, Haleakala Field Station, Hawai‘i. 22 pp.

Stone, Benjamin C. 1970. The flora of Guam. Micronesica 6:1-659.

Swarbrick, John T. 1997. Weeds of the Pacific Islands. Technical paper no. 209. South Pacific Commission, Noumea, New Caledonia. 124 pp.

Sykes, W. R. 1977. Kermadec Islands flora: an annotated checklist. New Zealand Department of Scientific and Industrial Research Bulletin 219, Wellington. 216 pp.

Tassin, Jacques. 2005. Jacques Tassin (IAC-CIRAD), personal communication.

U.S. Dept. Agr., Agr. Res. Serv. 2011. National Genetic Resources Program. Germplasm Resources Information Network (GRIN). Online searchable database.

Wagner, Warren L./Herbst, Derral R./Sohmer, S. H. 1999. Manual of the flowering plants of Hawaii. Revised edition. Bernice P. Bishop Museum special publication. University of Hawai‘i Press/Bishop Museum Press, Honolulu. 1919 pp. (two volumes).

Whistler, W. A. 1988. Checklist of the weed flora of western Polynesia. Technical Paper No. 194, South Pacific Commission, Noumea, New Caledonia. 69 pp.

Wu, Te-lin. 2001. Check List of Hong Kong Plants. Hong Kong Herbarium and the South China Institute of Botany. Agriculture, Fisheries and Conservation Department Bulletin 1 (revised). 384 pp.