Black Medic (Medicago lupulina): Nitrogen-Fixing Weed with Tiny Yellow Flowers

Overview

Black medic (Medicago lupulina) is a low-growing, annual or short-lived perennial legume common in lawns, roadsides, and disturbed soils worldwide. It has trifoliate leaves (similar to clover but with a longer central leaflet stalk) and small, bright yellow flower heads in late spring to summer, followed by coiled, black seed pods.

Botanical Details

• Family: Fabaceae (legume family) – formerly Papilionaceae
• Genus: Medicago
• Species: lupulina

Ecology & Uses

Nitrogen-fixer; improves soil fertility. Indicates compacted, low-nitrogen soils. Edible leaves and seeds (sprouted). Flowers attract bees. In lawns, often tolerated as a beneficial "weed." Control by improving soil fertility, aeration, and mowing high. Can be used as a cover crop/green manure.