Medicago arborea is a plant species of the genus
Medicago. Common names include
moon trefoil,
shrub medick,
alfalfa arborea, and
tree medick. It is found throughout Europe and especially in the Mediterranean basin, primarily on rocky shores among shrubby vegetation. It forms a
symbiotic relationship with the bacterium
Sinorhizobium meliloti, which is capable of
nitrogen fixation. It is the only member of the genus
Medicago which is used as an ornamental.
M. arborea is sometimes misidentified as
Cytisus, which it resembles.