If they are annual grasses, I'd just mow short, aggressively rake to stir up the soil and reseed. If they are broadleaf weeds, I'd do the same thing and also apply a broadleaf herbicide in mid-October, since you can apply most broadleaf herbicides to seedlings after they've been mowed four or more times. Be sure to keep the reseeded areas watered to stimulate germination and establishment. The information given herein is supplied with the understanding that no discrimination is intended and no endorsement by the Purdue University Cooperative Extension Service is implied. Any person using products listed assumes full responsibility for their use in accordance with current direction of the manufacturer.
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