Medicago arabica (Spotted Bur Medick)
Species: M. arabica
Binomial name: Medicago arabica
Common names: Spotted Bur Medick, Spotted medick, Spotted burclover, Heart clover, Calvary clover.
Medicago arabica is native to the Mediterranean basin but is now found throughout the world. It is an annual with smooth, heart-shaped leaves with a dark spot in the centre of the leaf. Stems contain large stipules and have small yellow flowers that develop into small, distinctive, spiny burs. It is common in the north of the North Island and the east of the South Island in open pastures, waste places, especially near the sea.
It forms a symbiotic relationship with the bacterium Sinorhizobium medicae, which is capable of nitrogen fixation.
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