Creeping cinquefoil
Potentilla reptans
It is a creeping perennial plant native to Eurasia and Northern Africa and naturalized elsewhere. Its trailing stems root at the nodes. Leaves are borne on long stalks. It blooms in June - August with yellow flowers (about 2 cm in diameter) that have 5 heart-shaped petals. It is quite common. Could be easily confused with silverweed. The butterfly known as the Grizzled Skipper is known to favour this plant which is often found growing in crushed masonry in the South of England.
Alcoholic extracts from roots of Potentilla reptans showed a moderate antimicrobial activity against common wound pathogens.
Potentilla reptans can be an invasive weed in lawns and flowerbeds and difficult to eradicate, particularly when it competes with and infests established groundcovers. All of the taproots must be dug up, or the plant will reappear.