Mature Pine Trees Have Huge Masses Of Twigs Covering The Trunks

Question From: Tomah, Wisconsin, United States
Q: The insides of several of my mature pine trees have huge masses of tiny twigs that are covering the trunk. They make the trunk look about 3-4 times the diameter it really is. It does not pull off, and it has no actual needles, but looks like masses of tiny branch like vines? It's hard to describe. I am afraid it will kill my trees. We have 12 trees planted as a wind block, and this is on 4-5 trees. The trees were purchased and planted by a Christmas tree farm about 10 years ago. This is the first year we have actually noticed this ?growth? or whatever it is. What is it? What should I do about it? Will it kill my trees? Thanks for helping!
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A: Linda, I would schedule and on-site inspection by a certified arborist in your area. He/she will be able to tell you what's up with your trees. Could be several things and a bad guess could cost you your trees. To find one in your area go to Best And Happy Yardening, Nancy.