I apologize for this delayed reply to your gardening question and hope it is still helpful to you.
Since your question is really several in one let me refer you to the following web site which has a lot of great info on having a lawn in Florida.
I suspect that grubs did get your grass based on your description. Contact your county extension office for free advice and publications on lawn care. They are a very helpful resource. Their contact info is:
Polk County Cooperative Extension Service
1702 Highway 17-98 South
Bartow, FL 33830
Phone: (863) 519-8677
Thanks for the question. Best wishes for a wonderful gardening year in 2007. Please stop in again soon!
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