Often confused with white clover, black medic has 3 leaflet, clover-like leaves. Low growing with trailing stems. Clusters of small, bright yellow flowers appear in late spring or early summer. See botanical illustration.
An annual that can persist as a perennial, black medic is common in lawns from May through September. It grows in dry, high phosphorus, compact soils and enjoys full sun. It will take over and thrive in areas with weak, patchy grass.
Encourage optimum turf growing conditions. Maintain adequate nitrogen levels with low to medium phosphorus levels. Keep turf adequately watered. Pull or dig shallow tap-roots when they appear. Aerate to relieve compaction.
Spot spray with post-emergent broadleaf herbicide containing triclopyr, clopyralid, or 2,4-D, MCPP, and dicamba.