Answer: Browning can have many causes ranging from poorly rooted sod to pest or disease to uneven watering to accidental overfertilizing or chemical exposure to dog urine and so on. It is very difficult to diagnose long distance. I would suggest raking out the brown spots and seeding over them. The new grass should blend in with your current grass. For a thick, lush lawn, be sure to water and mow on a regular basis and feed 4 times a year (April, June, September and late November). With regular maintenance, your lawn should be lush and green.
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