If you live here in the the Northeast United States, you may have noticed that pine trees have been dropping their needles this summer, when they should be doing that in the fall. This issue was discussed recently in a UNH Cooperative Extension Education Center Newsletter article, where the needle drop was referred to as "epic".
Curious as to exactly what is causing this disease, I took it upon myself to gather more factual information regarding this apparent tree disease. Specifically, I examined a red pine and three white pines, recording damage to the outside bark, inside bark, needle surface, and needle interior. What I found does not appear to match the symptoms of known pine diseases, specifically needlecast. Vermont officials seem to agree that we may be seeing something new, saying that this disease is still "under investigation".
All the disease data I've gathered on this pine disease is detailed in a set of over 40 photos contained within this website PDF file:
www.whitecanker.net/Pine needle drop analysis.pdf. Most of the photos were taken with a digital microscope so you can see exactly what sort of damage this disease is doing within the tree, as external views don't tell you much.
Remember, PDF viewers have the ability to zoom in to content, so you may want to use this feature to more closely examine some of the photos.
If you have additional information regarding this pine tree disease, I'd love to hear from you! In fact, we can all discuss it. Just reply to this note.
Don Peters
Nashua, NH
