Question
I have a black pine that is being killed by what appears to be little 1/2 inch long worms, or larvae, I'm not sure.  it has an almost cream colored segmented body with a black head and maybe six legs on the first two segments.  it has what appears to be two more legs on the last segment also.

Answer
There are many insects the can be found under the bark of dead or dying trees most of them are not the cause of the death but they are feeding on the fungi growing under the bark. Insect larvae are hard to id but if you want to find out what it is I would suggest you call the Maine Forest Service (state agency) and ask them for assistance. Their contact information is
Insect and Disease Lab
50 Hospital Street
Augusta Maine 04330

Telephone: 207-287-2431

OR their contact web page link for their 1-800 number is http://www.maine.gov/doc/mfs/mfs/contact.html

Ask for Dave Struble, he is a friend of mine and should be able to put you in contact with the right person.