Question
I live in Michigan, and i have three pine trees in my front yard. There is one tree, that has lost the pines at the top. The other two pine trees are fine, so i was inquiring could this be disease, or the result of insects? I looked to see if i could contact my department of forestry, but i found no information that would suggest that  michigan has a forestry dept. Any information you provide will be greatly appreciated.
Thank you

Answer
Sounds like one of the bark beetles possibly Ips Engraver since they attack the upper part of pines. I would call the Michigan Forestry they are in the Department of Natural Resources. here is the Forestry contact web page link. You can call the office closest to you and have them come out and take a look--an on the ground look is a lot better then me trying to determine the problem over the Internet.
http://www.michigan.gov/dnr/0,1607,7-153-30301-34287--,00.html