Answer: I had a little trouble tracking down the exact recipe for dethatching a lawn. Here is a formula for fertilizing; perhaps this is also reputed to break down thatch. Mix a can of beer, a can of Coke, 1 cup of ammonia, 1 cup Joy dish soap, and add water to fill a 20 gal container, and spray on the lawn. He adds antiseptic mouthwash for funguses, etc.
I don't have any experience with this method, so I can't vouch for it. If you search the internet (I used Infoseek) using the words "Jerry Baker", then a sub-search with "lawn", you'll get some interesting web sites. His books are also available from internet bookstores.
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