A lawn 70% filled with weeds.

[Chris]

IMO Chemical controls are the only way to reclaim a lawn gone to weed. It is very easy to keep a lawn weed free without any chemicals if you're starting from a weed free lawn. You just mechanically remove any that show up, and hope your neighbors do the same. In your situation though you need a weed killer made for lawns. It will likely take multiple applications but eventually you can get there.

[Perennialnorthernmichigan]

I agree with Chris. You are talking about your lawn, not garden. I believe. You can hire in a company to spray your lawn. I do it once a year. Or you could go to your local hardware and get a walk behind spreader, buy lawn feed/weed killer and do it yourself. If you do it yourself; Do it in spring or now for you and once in the fall. You'd be surprised!
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