Susan, if you're still with us, I just found this article from Texas A & M about this year's sod webworm outbreak that Cheryl mentioned. When I look at your picture some grass blades do look partly chewed but you also seem to have intact dead grass blades. It's possible to have more than one problem going on at the same time. But you mentioned having treated for bugs. Did you use something that would control caterpillars like sod webworms?
http://agrilife.org/harrishort...
I do think it would be a good idea to check for sod webworms with soapy water because it's better to be sure what the problem is. I remember when my late parents had a lawn problem and because their neighbour's and others' lawns nearby had been diagnosed by a lawn care company as having chinch bugs, they were going to apply an insecticide to theirs because the brown areas looked the same. When I visited and checked it out there were no chinch bugs, it was a fungal disease.
