Question
Hello.  I have a line of white pines in backyard.  Quite a few of them seem to be thinning out.  Needles falling off and some parts turning yellowish.  Took a look at the bows and needles and don't see any pests.  Could it be soil?  The area / soil is very damp through out spring..?

Can you recommend a good book, on trouble shooting these guys?
Any help would be great.
Thanks

Answer
This could be anything from just normal needle drop to a disease or insect problem. If the ends of the branches are still green it sounds like needle drop--pines have two sets of needles and when the new flush of needles bud out in the spring they will drop the older needles. When this happens there will be new green needles on the outer parts of the branches but the inner parts may be bare or turning yellow. Or Iron chlorosis may be a problem in high pH soils and causes needles to become yellowish.
I would suggest you contact the Ohio DNR division of Forestry, Forest health Program and ask them for assistance. the contact their is Dan Balser Administrator, Forest Health Program 614-265-7053, [email protected].

 
I really think it is not anything but they should be able to help you--they have Foresters throughout Ohio and can even come out to your place and take a look at the situation. Just ask.