Medicago lupulina | Black Medick
Black Medick, also known as hop medic, black nonesuch, blackweed, black clover, black medic clover, hop clover, black clover, black hay, English trefoil, hop trefoil, yellow trefoil, and hop clover, is an annual or short-lived perennial plant in the legume or clover family that’s native to Europe and temperate Asia. It has become established throughout the US and Southern Canada, found growing in dry, sunny areas like waste grounds, pastures, and along roadsides. The presence of Black Medick in large concentrations may indicate that the soil is poor in nitrogen.
The genus Medicago (shared with Alfalfa), is closely related to the True Clovers (Trifolium) and Sweet Clover (Melilotus). Like True Clovers, Black Medick has three leaflets and small yellow flowers that look nearly identical to Lesser Trefoil or Hops Clover. Black medick can grow erect, but is more often sprawled out close to the ground, spreading up to 2 feet across. Like other members of the legume family, Black Medick has a symbiotic relationship with Rhizobium bacteria that forms nodules on the roots and fixes atmospheric nitrogen into the soil. The nitrogen is utilized by the plant as well as other plants growing nearby. Although Medicago lupulina is classified as a cool season summer annual, in mild winter areas some plants may survive and act as a perennial. Plants that survive for more than one year may develop a deep tap root. Plants spreads via seed and will form large colonies if left undisturbed. Seeds can persist in the soil for years. Individual plants can be hand pulled and even larger plants are easy to pull out, particularly after rain has softened the soil
Black Medick is a good source of nectar for bees to make honey.
Type: Annual or short-lived perennial
Sun exposure: Full sun to part shade
Mature height: 2-8 inches
Mature width: 2 ft
Hardiness zones: 4-8