Indian Strawberry
Duchesnea indica
This member of the Rose family sports a solitary yellow, ½ inch (1.3 cm) wide flower rising from the axils of a leaf with three leaflets. Both the flower and fruit have a 3-toothed, green bract on their underside. The fruit resembles a small strawberry, but is inedible. This common lawn weed is naturalized from India (hence it's common and scientific names). Flowers bloom from April to July.