"if" you really want to do it right and have the time.
Spray round up on everything. Wait...
rototill it all up really well.
Water it well, Wait....
If weeds, grass etc grows, Repeat process above until everything is all dead. (if ants are still there, spray stuff on them as well)
This could take a few months...
Then till it up again add some good organic material, manure, compost etc.
and seed away!

Hi WW,

I'm sorry to respond to your questions with more questions, but it would help to know:

How many hours of sun do you think the lawn gets?

How much traffic will there be from children or pets, or otherwise?

How large is the lawn? Do you think you could supply one inch of water over the whole area once a week if necessary?

All of these things need to be considered before deciding on a plan.

That said (or rather asked...) the first thing you want to do is to have a soil test done. Based on your location, unless your lawn was very well cared for before, I would suspect that your soil is acidic and that you will need to start liming. But don't start on that before getting the test results back. And those results will tell you much more that you will want to know about nutrient deficiencies, etc.

Soil tests are offered relatively cheaply by the cooperative extension offices of the US department of agriculture. In your area, UMass would be the place to go, see the link below.

Yes, it's a minor hassle, but once done you will know where your soil is and what it needs. If you don't do it you will always be guessing.

Certainly keep posting questions in the meantime, but really, get that test done. You will be glad you did.

Paul

Here is a link that might be useful: UMass soil tests

I don't think you should spray any roundup, and I don't think you should do any rototilling.

Yes, you've got to get some stuff, and kill the ants.
In addition, you've got to put some fertilizer down, and you should only put down Bay State Organic Fertilizer, or Milorganite, those fertilizers won't burn the lawn in the summer heat.

Then plan on spraying some Weed B Gone before summer heat gets here. Get the hose-end sprayer and some weed b gone concentrate, and spray the entire lawn.

Now that you've got some fertilization, no ants, and the weeds killed, you'll be in a position to evaluate where you're at and what to do next.

Keep us advised.

Thanks for all of your responses. It's a big yard (one acre+). The back yard gets a lot of traffic with my kids and dog. Also gets a lot of sun through out the day. Unfortunately, I don't think I have the time, energy, and patience to kill the whole lawn, rototill and reseed.

I do think getting the soil tested is a good idea. That being said, I also think I'll try your approach Philes. What do you recommend for me to put down to kill the ants? Just a surface insect chemical, or should I put something down that gets surface insects as well as grubs, since I have to put it down over the whole lawn?

Also, regarding the Weed B Gone, do they make a large enough quantity of concentrate to spray a one acre lawn?

And is this the correct order to treat the lawn:

1. Apply insect killer
2. Apply Weed B Gone
3. Apply Milorganite

Finally, after all of the above, should I reseed?

Thanks again,

William

As Tim the Tool Man Taylor would say, what you need is more power.

Seriously, with that much lawn you are never going to have the time and energy to do much of what it would take to treat it as a lawn as opposed to whatever nature would do with it without some decent sized equipment.

Aerating, seeding, mowing, not to mention leveling, and tilling, etc., all will need a lawn tractor or rented equipment.