Medicago polymorpha L. Burr Medic
Sp.Pl. 2:779 (1753)

Conservation Code: Not threatened
Naturalised Status: Alien to Western Australia
Name Status: Current

Brief Description
Amanda Spooner, Friday 17 August 2007

Prostrate or ascending annual, herb, 0.04-0.2 m high, to 0.5 m wide. Fl. yellow, Jan to Feb or May or Jul to Nov. Black, brown, white, yellow or grey sand, ironstone gravel, orange-brown sandy clay, granite. Flood plains, valley slopes,dunes, clay flats, roadsides.

Distribution

Beard’s Provinces: Eremaean Province, Northern Province, South-West Province.

IBRA Regions: Avon Wheatbelt, Carnarvon, Coolgardie, Dampierland, Esperance Plains, Geraldton Sandplains, Jarrah Forest, Mallee, Murchison, Nullarbor, Pilbara, Swan Coastal Plain, Warren, Yalgoo.

IBRA Subregions: Avon Wheatbelt P1, Avon Wheatbelt P2, Cape Range, Central band, Nullarbor Plain, Eastern Goldfield, Eastern Murchison, Edel, Fitzgerald, Geraldton Hills, Hamersley, Lesueur Sandplain, Northern Jarrah Forest, Perth, Pindanland, Recherche, Southern Cross, Southern Jarrah Forest, Tallering, Warren, Western Mallee, Western Murchison, Wooramel.

IMCRA Regions: Central West Coast, Leeuwin-Naturaliste, WA South Coast.

Local Government Areas (LGAs): Albany, Ashburton, Augusta-Margaret River, Bayswater, Broome, Bruce Rock, Bunbury, Busselton, Cambridge, Canning, Capel, Carnarvon, Chittering, Cockburn, Cranbrook, Cunderdin, Dalwallinu, Dandaragan, Denmark, Esperance, Gosnells, Greater Geraldton, Harvey, Irwin, Jerramungup, Joondalup, Kalamunda, Kalgoorlie-Boulder, Lake Grace, Manjimup, Melville, Menzies, Merredin, Mingenew, Mount Magnet, Mount Marshall, Murchison, Murray, Narembeen, Narrogin, Nedlands, Northampton, Nungarin, Perth, Ravensthorpe, Rockingham, Shark Bay, South Perth, Stirling, Subiaco, Wagin, Yalgoo, Yilgarn, York.

Management Notes (for the Swan NRM Region)
Kate Brown and Karen Bettink, Thursday 21 December 2017

Alternative Names. Trefoil, Toothed Medic, Creeping Burr, Medic Burr, Rough Medic.

General Biology. Growth form. Herb. Life form. Annual. Reproduction. Seed. Dispersal. Animals (adhesion). Toxicity. Occasionally toxic to livestock. Seedbank persistence. 5+ years.

Notes. Has a taproot and nitrogen-fixing nodules. Prefers high phosphate levels and is more abundant on heavy alkaline soils. Germinates in autumn to winter, flowers in spring and dies with the onset of summer drought and high temperatures. Produces hard coated dormant seed. Softening of hard seeds occurs during auutmn rather than summer, resulting in fewer seedling losses from false breaks of season.

Additional information. Origin. Mediterranean. History of use/introduction. Pasture, honey production.

Suggested method of management and control. Relatively tolerant to glyphosate, grazing and mowing. Hand pull isolated plants in winter before flowering. Lontrel® at 10 ml/10 L + wetting agent provides effective control in early winter. Otherwise metsulfuron methyl 0.1 g/10 L + wetting agent or 1 g/10 L of Logran® applied in early winter provides reasonably selective control. Repeat annually for several years. Read the manufacturers' labels and material safety data sheets before using herbicides. For further information consult the Australian Pesticides and Veterinary Medicines Authority to determine the status of permits for your situation or state.

Management Calendar

Calendar Type Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Comments
Germination       Y Y Y Y Y Y Y      
Active Growth           Y Y Y Y Y Y    
Flowering         Y Y Y Y Y Y Y    
Fruiting               Y Y Y Y Y  
Herbicide Treatment           Y Y Y          

Legend: Y = Yes, regularly, O = Occasionally, U = Uncertain, referred by others but not confirmed.

 

References

  • Avendaño, J., Del Pozo, A. & Ovalle, C. (1999) Hard seededness under field conditions of Medicago polymorpha during five softening seasons in the Mediterranean zone of Chile. In Buchanan, J.G., L.D. Bailey, and P McCaughey (eds.) Proceeding of the XVIII International Grassland Congress, Winnipeg and Saskatoon, Canada. 1997. CD version, Session 19:89-90.
  • Brown, K. & Brooks, K. (2002) Bushland Weeds: A Practical Guide to their Management. Environmental Weeds Action Network, Greenwood.
  • Hussey, B.M.J., Keighery, G.J., Dodd, J., Lloyd, S.G. & Cousens, R.D. (2007) Western Weeds. A guide to the weeds of Western Australia. 2nd Edition. The Plant Protection Society of Western Australia, Victoria Park.
  • Lloyd, D.L., Taylor, G.B., Johnston, B. & Teasdale. K.C. (1997) Patterns of seed softening and seedling emergence of nineteen annual medics three years after a single crop in southern Queensland. Australian Journal of Experimental Agriculture, 37 (7): 767-778.
  • Moore, C.B. & Moore, J.H. (2002) Herbiguide, the pesticide expert on a disk. Herbiguide, PO Box 44 Albany, Western Australia, 6330.
  • Moore, J.H. & Wheeler, J. (2008) Southern weeds and their control. DAFWA Bulletin 4744.
  • Nichols, P.G.H., Stockdale, M., Malik, A.I. & Colmer, T.D. (2008) Salt tolerance in germinating seedlings of annual pasture legumes. In 2nd International Salinity Forum. Salinity, water and society - global issues, local action, 30 March - 3 April 2008, Adelaide Convention Centre, Adelaide. URL: http://www.internationalsalinityforum.org/Final%20Papers/nichols_A7.pdf.
  • Taylor, G.B. (1996) Incidence and measurement of autumn seed softening within Medicago polymorpha L. Australian Journal of Agricultural Research, 47 (4): 575 - 586.
  • Wagner, L.K. & Spira, T.P. (1995) Germination, recruitment, and survival in the weedy annual Medicago polymorpha in successive wet and dry years. American Midlands Naturalist, 131 (1): 98-108.
  • Winans, B. & Graves, W. (2003) California Invasive Plant Inventory Assessment Form - Medicago polymorpha (California burclover). California Invasive Plant Council URL: http://www.cal-ipc.org/ip/inventory/PAF/Medicago%20polymorpha.pdf - Accessed July 2010.

Project information and acknowledgements