The first step in diagnosis of any plant health problem is verification of the tree species. The photos don’t quite show enough detail for me to verify that these are Jack Pine. In fact, they look more like Scotch Pine from what I can see in the photos. How did you determine the tree species? If you can send better photos of the bark, needle clusters, and cones, I can help verify the species ID. 

The blue-green stuff on the branches is lichen. You can read more about these harmless organisms here: https://www.canr.msu.edu/news/what-s-that-growing-on-my-tree

I think these are Scotch Pines (Pinus sylvestris), not Jack Pine. You can compare the cones to the cones in these photos of Jack Pine (Pinus banksiana): https://michiganflora.net/species.aspx?id=1922

Of course, it very possible that you have both kinds of pine growing side-by-side. However, they will not be susceptible to the same disease and pest problems. 

Scotch Pine is highly susceptible to a number of fungal diseases of the needles and shoots. This article from MSU Extension might help: https://www.canr.msu.edu/news/why_are_my_pine_trees_turning_brown 

Scotch Pines are also highly susceptible to pine wilt disease, which is carried from tree to tree by beetles that bore into the trunk. Inspect the trunk for signs of attack by wood-boring longhorn beetles (Sawyer beetles). You can also have a sample analyzed by the MSU Plant and Pest Diagnostic Laboratory. Their website has contact info and instructions for how to submit a sample: https://www.canr.msu.edu/pestid/