Answer: If the lawn is spongy, it may be a result of thatch build up. Check by digging out a sample of lawn. Expect to see some thatch (dead stolons/roots) but if the straw-brown thatch build up is in excess of a half an inch, dethatching will fix the problem. Power dethatchers rake out the excess thatch along with some of the live grass but you can either overseed (if you have bermuda) or wait for St. Augustine to fill in the bare spots. This should take care of the problem with ruts and spongyness. Best wishes with your lawn.
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