Have you talked with the people at your local office of the Texas A & M Cooperative Extension Service? If not they are in the best position to answer your questions.

Reply on another site diagnosis is "Slime Flux". More of a symptom than outright cause. Consan, available to the public, is recommended to treat these symptoms. And of course, maintaining very good growing conditions reduce the causes of several injuries to the bark that set up conditions favorable to slime flux. In my case, "sun scald" may have been the original injury.