Is my grass dormant or dead? I’ve had this questions posed to me many times over the last couple of weeks. The heat wave seems to be over, but it left a huge wake of destruction in its path. Many yards with full exposure to the sun have spots that have completely been burned up and will not return. Other areas have spots that simply are taking a nap, or have gone dormant. A good way to tell is to envision bristles on a brush, if your brown grass is still standing upright like bristles on a brush, no need to worry. If the grass is laying/matted down, then most likely it is dead. These thin/dead areas will not fill back in on their own, seeding must be done this fall to recover those areas lost.