Burr clover is a plant that grows small yellow flowers and little burrs, which stick to your feet as you walk through the lawn. The leaves shade the grass and cause it to die back or not grow, creating bare patches in your lawn in the late fall, after the clover dies out. If you have burr clover growing on your lawn, remove it as quickly as possible to maintain a lush lawn.
Pull small clumps of burr clover with your hands before it goes to seed. The yellow flowers are an indication that it is ready to distribute seeds. If it hasn't gotten to this point yet, then pulling it up is quick and easy. It generally goes to seed in the fall. Get the roots of the burr clover as well as the tops.
Mow your lawn at your normal mowing height, walking back and forth across the lawn in a particular angle.
Lower the blade about 1/2 inch and mow the lawn again at an angle perpendicular to the first mowing. Repeat, lowering the blade again, if the clover leaves are still present. You want to mow until the leaves of the burr clover are removed. This allows sunlight to get to the grass blades.
Spray the clover with an herbicide specific to killing clover. Wait and spray when and if the leaves grow back. A selective herbicide is best, since it is formulated to kill certain weeds and not your grass.