David Monniaux, Wikimedia.org
English lawn daisy weeds grow and spread quickly, making them an aggressive species to deal with. They have flower heads with white petals surrounding a yellow center. The basal leaves are smooth and broad toward the top and narrow at the base. Some leaves may also have hairs, though most are smooth and slightly toothed.
Seedlings usually germinate from April to September in warmer climates such as the South or California. Once they're established, these weeds take hold quickly. Apply postemergent herbicides with penoxsulam in late summer and early fall to keep this perennial from spreading.