I have white pine trees which were planted in 2003 - over 3,000. I noticed a...
It looks like pine bark adelgid. This aphid like insects attaches to the trunk of eastern white pine trees with its needle-like mouth parts and feeds on the sap. They usually occur in plantations when the trees become crowded. At this time the trees are stressed and often become more susceptible to the pine bark adelgid. Usually the most stress trees are the first to become infested are the most severely impacted.
A proper thinning may be the best way to deal with the problem. Feel free to contact me f you would like to discuss thinning options.