4.  Spotted Spurge
A low-growing weed with oval pale to dark green leaves ¼ to ¾ inch long appears in the lawn. Each leaf may have a purple spot. Stems ooze milky white sap when broken. The leaves are slightly hairy on the underside and smooth on top. Tiny pinkish white flowers bloom in midsummer. The numerous pale green stems fan out on the soil surface and over the top of the grass, forming mats up to 2 feet in diameter.