Answer: I can't really tell by your description whether the trees are diseased or have been attacked by insects. The white gook is sap, either from injury or from an internal disease. Wish I could give you a concrete answer, but without seeing the trees, I really can only venture a guess. You might take one of the affected branches to your local cooperative extension office for positive diagnosis. Once they physically see the problem they should be able to suggest control measures.
Best wishes with your pines!
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