Plantain (Plantago species)
Plantains are perennials that form rosettes of dark green leaves marked from end to end with distinctive parallel veining.
Leaves of P. lanceolata (buckhorn plantain) are long and narrow; those of P. major (broadleaf plantain) are broadly oval. They love damp, heavy soil.
To reduce infestations in lawns, keep the turf thick through consistent fertilizing; aerating will help, too. Dig out plantains before they set seed. Be sure to remove as much of the roots as possible (a dandelion weeder is helpful here), since these weeds can regrow from any pieces of the rootstalk that remain.
For chemical control, use a preemergence product or spot-treat plantains in the garden with glyphosate, taking care not to get the chemical on desirable plants.