I assume you mean you have pasture type or K-31 tall fescue intermixed into your lawn that is primarily bluegrass, perennial rye, fine fescues, or a combination of those grasses. It is wrong to say all tall fescue is undesirable to have in a lawn. Turf type tall fescue produces a very nice turf with the newer cultivars being fine bladed and dark green, and will blend with many cultivars of KBG. If you remove the tall fescue patches, and you have KBG, the KBG should fill in bare areas, but only if your soil is good, and it is well fed. Perennial rye won't spread, and creeping red fescue will take a long time to fill in areas, a lot longer than the weeds will. If the tall fescue is just left by itself, the other grasses won't "squeeze it out". Instead of pulling the TF, you can spot spray any areas with Round-Up. That will kill it and the other grass wherever you spray, leaving a brown spot in 2 weeks. There is a specialty chemical that will selectively remove TF called Certainty. It is pricey, and not the easiest stuff to use as it can harm other grasses if overapplied. It will also kill any turf type tall fescue you might have in your lawn.

With regards to your soil. You say you have clay, and a lot of people think this is the case. Mass isn't particularly well known for clay, but I'm sure their are pockets in the state. You should spend the time from now, till you seed to get your soil in better shape. This means having a soil test done (I recommend Logan Labs, $20 basic soil test or you can send it to Umass, which is $5 bucks cheaper). You can also do a jar test to see if you soil is mostly clay. When you get your soil test back, you can then add amendments to correct any imbalances or deficiencies. If you are saying to yourself "I don't need no stinking soil test, my grass grows fine", then you are only fooling yourself. I was the same way, until I did one, and saw how bad my soil really was (back yard pH was below 5). It will save you money in the long run too by not overapplying fertilizers, and amendments.

Thank You "tiemco" for all of your suggestions. Do you have an address for Logan Labs?

www.loganlabs.com

Their site will tell you how to take samples. You can use ziploc bags, and you don't need an account, just send a check with the form, that will set up an account for you.