Return to floridaturf.com   A key to solving the problem:  This is just a preliminary example of how to classify (and maybe solve) the problem.  You might try making up your own key or give suggestions.
Turf is brown or yellow
Turf is not brown or yellown
Turf is turned up or there appear to be physical holes
Turf is not turned up
 You apparently have some other problem for which this simple key is not ready to handle.  Are there weeds?   Does the turf fail to respond to fertilizer?  Do you have a thatch problem?  Does your lawn scalp or is it full of seedheads?  These kinds of problems are often influenced by the physical environment, for example, seedhead production is most abundant in newly established (first year) turf and during the dry season (March to May in south Florida).  If your lawn is thatchy, your best bet is to back off a bit on fertilization and watering and if need be, topdress or (carefully) verticut.