Family: Fabaceae

Medicago polymorpha (California bur-clover, bur medic) is an herb native to Europe, temperate Asia and Northern India. The leaves and shoots of this plant are edible, but only the leaves are eaten raw. This plant is also edible to all types of livestock, despite the fact it has prickly fruit. It is reported to be widely naturalized worldwide including the Hawaiian Islands of Kuaihelani (Midway atoll), Kauaʻi, Oʻahu, Lanaʻi, Molokai, Maui, and Hawaiʻi. Although this plant is used as fodder for livestock, it may cause photosensitisation in horses, occasionally red gut in sheep, and bloat in cattle, but generally a desired, palatable plant. Its rapid maturity, ability to modify soil chemistry, and persistent seeds (5+ years longevity) may create issues with this plant being difficult to eradicate. 

High Risk Traits:

• Broad climate suitability, and elevation range exceeds 1000 m, demonstrating environmental versatility
  
• Naturalized in regions with tropical climates
  
• Naturalized on Kauai, Oahu, Lanai, Molokai, Maui, and Hawaii (Hawaiian Islands) and widely naturalized elsewhere
  
• Often regarded as an escaped, weedy plant of crops and disturbed natural areas, but often considered innocuous or a desirable fodder plant
  
• Other Medicago species are invasive
  
• Spiny pods on plants in Hawaii, but spineless cultivars exist
  
• Possibly allelopathic
  
• May cause photosensitisation in horses, occasionally red gut in sheep, and bloat in cattle, but generally a desired, palatable plant
  
• Tolerates shade, although most often occurs in high light environments
  
• Tolerates many soil types (not limited by substrate)
  
• N-fixing, and may modify soil chemistry
  
• Reproduces by seeds
  
• Self-fertile
  
• Able to reach maturity in one growing season
  
• Seeds dispersed by external attachment of pods to animals, internally by livestock and waterfowl, as a crop and wool contaminant, by water and both intentionally and accidentally by people
  
• Seeds long lived (5+ years), and can form a persistent seed bank
  
• Tolerates mowing and grazing

Low Risk Traits:

• Despite reports of weediness, also regarded as a desirable pasture plant
  
• Provides fodder for livestock
  
• Sensitive to herbicides, which may provide effective control if removal is desired