After overseeding, you want to wait as long as possible to mow. If you must, you must. Berfore overseeding, try to cut the lawn down to an inch and a half and bag the clipping--or get it down to what you can in what time you have to mow. The more you lay off your lawn after overseeding, the better it is for your seedlings. After a few weeks, they may be strong enough to take the trampling.

I'll offer that for overseeding you can mulch mow right after they have seeded, you can mulch mow after they have aerated and overseeded, you can mulch mow before they aerate and overseed. Your concern is once the seed germinates, which is about 7-15 days after the seed makes soil contact and stays moist. Once germinated it is best to give it about 2 weeks before cutting again.

re Over Seeding - How will you irrigate to maintain constant moisture on the new seed, over 1.5 acres?

With core aeration and at this time of the year, you can be very successful letting mother nature take care of things.

What is involved with overseeding? I live in Syracuse NY, and grant you it may be too late for overseeding, I wondered hwo it is done?

Do people just spread it over the lawn or do you have it power-raked first then lay it down?

or does a compnay normally come sin and use a machine that slits the lawn and puts the seed down? (I think thats for new lawns)

Many people have use the slit seeder that you mentioned or core aerate and broadcast seed afterward. You can also power rake and broacast seed. In any case, you are best to maximize soil-seed contact the way you think best. Broadcasting seed without some kind of soil prep may not be the most efficient or productive.