WSU Extension


Weeds : Black medic : Medicago lupulina
(revision date: 4/7/2021)

Family: Fabaceae (Leguminosae)
Cycle: Annual
Plant Type: Broadleaf

Use Integrated Pest Management (IPM) for successful weed management.

Black medic is very clover-like in appearance and is sometimes called Japanese clover. Leaves are alternate on the stems and divided into three leaflets. The center leaflet has a short, jointed stalk, while the side leaflets are without stalks. Each leaflet is broadest near the tip and slightly toothed at the tip only. The leaf veins are very obvious. A pair of stipules (small, leaflike appendages) are present where each petiole joins the main stem. The four-angled stems are prostrate or nearly so and branch from the base of the plant. Tiny yellow flowers are borne in small, dense clusters on stalks arising in the leaf axils. Individual flowers are about 1/8 inch long, while flower clusters are 1/2 to 3/4 inch long. Seeds are borne in small, kidney-shaped pods that turn black at maturity. The pods are hairy but not spiny. Black medic may be an annual or a short-lived perennial. California burclover, Medicago polymorpha, has spiny pods but otherwise resembles black medic in appearance.
Black medic grows in gardens, lawns, and waste areas, commonly on poor soils.

Management Options

Non-Chemical Management
  • Cultivation (rototilling or hoeing) will effectively eliminate plants.
  • Careful digging is useful to manage weed populations. However, digging can carry undesirable weed seed to the surface and foster further germination.
Select non-chemical management options as your first choice!

Chemical Management

Apply according to label directions. Glyphosate products should be applied as spot treatments only! NOTE: Some ingredients listed here are only available in combination. Read the label carefully on combination products to make sure the product is suitable for your specific situation.

Landscape areas
  • glyphosate
  • products containing triclopyr
Turf areas
  • triclopyr
  • 2,4-D + MCPP + dicamba
Bare ground areas
  • glyphosate
  • triclopyr
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Caption: Black medic
Photo by: T.W. Miller
Caption: Black medic
Photo by: T.W. Miller
Caption: Black medic flowers
Photo by: D.G. Swan
Caption: Black medic seedling
Photo by: D.G. Swan
Caption: Black medic patch
Photo by: J.A. Kropf