Gardeners know that the secret to healthy grass is fertilizer. But too much fertilizer is too much of a good thing. Lawns that are over fertilized will exhibit yellowing from nitrogen burn. That's because the excessive amounts of nitrogen in the fertilizer will pull moisture out of the roots of grass plants. As the plants desiccate, they will turn yellow, wilt and collapse. Once lawn grass turns yellow, it is probably already dead. Your next step is to remove the dead patches of grass and extra nitrogen in the lawn, and replace it.
Water your lawn deeply with one inch of water every 10 days. Use a rain gauge to measure the amount of water you are using. Nitrogen is easily leached out of the soil and carried away by water. Watering your lawn will remove extra nitrogen.
Cut your grass to one and a half inches tall with a lawn to make it easier to remove. Grass normally should be cut to two inches tall.
Rake away dead grass from the yellow patches in your lawn.
Remove the roots of dead grass with a spade. A spade is a flat, shovel-like implement with a sharpened end suitable for cutting sod.
Rake furrows into the patches of bare soil.
Cut sod squares to match the patches of bare soil, and put them in place.
Roll over the sod with a sod roller to force the roots in contact with the damp, bare soil.
Water your sod up to four times daily with a quarter inch of water until the roots become established. Gradually taper back watering to one inch every 10 days.