Here is the deal-customer has sod that is mostly kentuncy bluegrass. The have couple of dogs. Throughout the years they have patched the brown spots created by the dogs. They used a variety of different patch seeds throughout the year therefore they have clumps of grass that are different then the sod. They now have the dogs confined to just a small area of the yard and would like to get the lawn looking nice again. I am faced with a couple of problems. First, the areas where there is still the original sod, the grass doesn't' look real good. It is thin and has a lot of brown in it. There is clumps of grass, I think tall fescue, mixed throughout a lot of the lawn. There is just one area that looks good. It is not the original sod, but I think it is Kentucky bluegrass. It is a small area. I don't know if I should kill off all the grass and start new. Or I should kill, or rip out the fescue, seed with k. bluegrass and then overseed the existing k. bluegrass with more seed. The soil in the area is sandy. The yard is fertilized regularly. It has not been aerated in a while but it was dethatched in the spring. Any suggestions? Pic 1 -the original sod Pic 2 - fescue clump Pic 3 - overview of lawn. lower right is the good k. bluegrass. above is the thin sod with the clumps of fescue Pic 4 - up close of the k. bluegrass that I think looks good. It hasn't't't been mowed yet, so a but long. But this is what I would like the whole yard to look like. It is not the sod, but patch that was just to fix an area the dogs destroyed.