James: I work in an Extension office in Central Illinois, so I have been researching your problem on the Internet. I am at a loss for what is causing your problem. HOWEVER, you have a very knowledgable Texas Extension Horticulture person in your area. His name is Dale Groom and he is located at the Dallas regional Center. His phone number is: 214-904-3053 and his e-mail is: dalegroom@tamu.edu If you e-mail Dale, it would help if you could send a picture of the problem. I am sorry that I could not be more help, but your lawn grasses do not grow this far north.