Answer: It may sound like an odd combination, but since bermuda is a warm season grass and fescue is a cool season grass, bermuda is often overseeded with fescue so the lawn stays green all year around. Getting one grass out of another is not easy. If the area is allowed to go through drought the bermuda will outlast the fescue.
A core aerator is superior to a spike aerator. A core aerator will remove one inch by three inch plugs from the lawn. Leave the plugs on the lawn and they will dissolve in rain or water from the sprinklers. After aerating spread a thin layer of sand or compost over the area and water it in well. The sand or compost plus the soil from the plugs will work their way down into the holes left by the plugs.
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