Medicago polymorpha
FABACEAE
Burr Medic, Burclover, Toothed Medick, Trefoil
Annual weed found in lawns, roadsides, agricultural lands & disturbed sites. Germinates from April to October. New seedlings have oblong leaves. Later leaves are trifoliate, clover like in shape.
Flowers from May to November, a tiny pea shaped yellow flower that cluster into flowerheads at the ends of the stem. Stems are up to 60cm long which often root at the nodes.
The fruit pod is an annoying tightly coiled seed pod with rows of prickles on the outside edge, about 6-7mm across. Green & soft when young but maturing brown & harder. Each pod has several yellow or tan kidney shaped seeds. They cling to fur, fleece, clothing. Uncomfortable in lawns. Seeding from Aug to Dec, noticeable right now. Seeds remain viable 5+ years.
Unfortunately removing top growth will not eradicate this weed. Herbicide treatment is best done on seedlings. So look out for seedlings next June
Hand pulling young seedlings before flowering is an organic Autumn job. They form long trailing stems which take roots at the nodes, this can be pulled up , wear gloves. Dispose of carefully into a garbage bin. To pick up scattered burrs, throw a old camper mattress down & pick off & dispose of the burrs.
Occasionally it is toxic to livestock.