I have a lawn disease ,either dollar spot or brown patch. It is at tall...
Brown patch has been very prevalent this year in Maryland lawns. Your best strategy is simply to continue providing regular maintenance and wait till early September. Tall Fescue turf grass will typically grow out of 'brown patch'. This disease is a foliar disease and does not always kill the crown or roots. You should discover that most of the brown areas will green up as the weather conditions moderate. You may have lost some turf grass, and if so, early September is a good time to top seed and nurture your lawn into a healthy turf. Do all of your fertilization between Labor Day and mid November and avoid fertilizing in the spring and summer.
Raking the brown areas could damage the crowns and prevent further growth.