clover

The best way I understand to eliminate clover is through an early-spring application of corn gluten. A natural and biodegradable byproduct of corn processing, corn gluten acts as a new-growth inhibitor that stops seeds from germinating. Over a period of about a month, it biodegrades into nitrates that will fertilize your lawn. It has absolutely no deleterious effects on the lawn, the worms or the other beneficials that live in the lawn, nor upon plants with established root systems. You apply it in early spring, when your first flowers start to bloom, about six weeks before last frost.

Six weeks after you apply the corn gluten, overseed your lawn. The new grass plants will gobble up the space left by the weeds and will make it difficult for new weeds to get established later in the year. In the space of a few growing seasons, the yard should be virtually completely free of not only clover but other weeds as well.

I'm generally content to let my clover be since it aids the biodiversity of the lawn and adds nitrates to the soil.