Yellow Flowered Forbs

Yellow Flowered Forbs
Black medick
Black mustard
Curveseed butterwort
Dalmatian toadflax
Dyer's woad
Floating primrose-willow
Globe chamomile
Leafy spurge
Little hogweed
Maltese starthistle
Mediterranean sage
Perennial sowthistle
Perennial wallrocket
Rush skeletonweed
Saharan mustard
Sicilian starthistle
Spiny sowthistle
Tansy ragword
Texas blueweed
Wild mustard
Wooly mullein
Yellow salsify
Yellow starthistle
Yellow sweetclover
Yellow toadflax


Black Medick
Medicago lupulina L. (Pea family, Fabaceae)


Shallow, taprooted, low, trailing winte r annual or short-lived perennial forb, with prostrate or ascending stems up to 30 inches long; where thick stands develop, stems may become erect, obtaining heights of 18 to 24 inches; 4-angled stems are typically purple at the base, hairless or more rarely with some short hairs, although older stems become less hairy; they branch occasionally.

Leaves: Alternate, compound leaves are trifoliate (cloverlike); younger leaves, toward the stems tips, have short hairy petioles; older leaves have longer petioles (up to 1-3/16 inches long); paired stipules at petiole base are lanceolate to ovate and variable in size; leaflets are up to 9/16 inch long and about half as wide; medium to dark green, wedge shaped or obovate, hairy or nearly hairless, finely toothed with prominent veins.

Flowers: Flowers February to December; 2 to 8 small, bright yellow flowers are borne in clusters about 1/2 to 3/4 inch long; each flower is about 1/8 inch long; when fully open, it has a pealike floral structure with an upper standard and lower keel.

Fruit: Fruit is a spirally twisted, thick-walled pod; each pod is black, about 1/8 inch long and contains a single dark seed that is somewhat flattened and kidney shaped, less than 1/8 inch long.


Cultivated and disturbed or degraded sites in meadows, grassland, woodland, and forest communities, and roadsides within elevations that generally range from 4,000 to 8,000 feet.


Reproduces by seed; one well-developed, vigorous, plant may produce more than 1,000 seeds.


Native to Eurasia and Africa; black medick easily spreads and can form large colonies and where it is allowed to grow undisturbed, black medick may displace native species. Prior to fruiting, black medic could be confused with burclover. This species generally occurs as a weed in wildland areas of the Southwestern Region rather than as an invasive plant.

Collage of images of black medick


Forest Service Shield
Invasive plants and weeds of the national forests and grasslands in the southwestern region
Black medick flowers and foliage Black medick trifoliate leaf Black medick flowers Black medick plants