Answer: There are several things that can cause brown spots in lawns: dog urine, fungal diseases, cool season grasses dying out in hot weather, or chemical burn (too much fertilizer). I'd rake out the damaged turf, scratch the soil lightly and then reseed. Cover the seeds with some peat moss to help hold in moisture and keep birds from feasting on the seeds. Keep the reseeded area moist and the grass should pop up within a week.
Best wishes with your lawn!
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