|Based on the information in your question, I am not certain which specific problem is affecting your pine. It might be pitch canker which is a fungal infection (Fusarium) that causes resin to leak out of lesions on the bark and stunts the plant. It is generally fatal, unless you are able to remove the lesions by pruning. Prevention is somewhat limited to replacing infected plants with something else that is not prone to infection. Since it is difficult to diagnose this type of problem long distance, I would suggest you work with your extension service. In Maryland, they have an extensive web site and also a toll free service for Maryland residents (listed on the web site). They should be able to help you diagnose the problem with more certainty and if chemical controls or preventives are recommended in your state, they will have the most up to date information on what to use and how/when is best to use it.
I hope this helps.