What is killing my pine trees under the bark i see trails maybe from bugs?

Answer 1

maybe the pine bark beetle....

http://www.google.com/search?hl=en&rls=com.microsoft%3Aen-us&q=pine+bark+beetle

if it's been at your tree for a while, you may well lose the tree....I was out west in May and was appalled at the number of pine trees there that were dead and dying from this pest....

if you don't see anything like what's in the Google lists, have an arborist look at the tree and soon....