Read an article in the Conway Daily paper that there is actually a fungus going through the pines that is making the needles brown and fall off. But it is not supposed to be detrimental to the trees. they should bounce back according to the article.
"Forest Insect and disease leaflet Number 44 from the Us department of Agriculture forest Service.
Brown spot needle blight caused by a fungus called scirrhia acicola, that delays growth and causes mortality in long needle pines."
http://www.na.fs.fed.us/spfo/pubs/fi...brown-spot.htm