Question
Dear Mr. Jim Hyland,
I live on 1-1/2 of woods in southern/central Tennessee.  My largest and most beautiful tree (and I am embarrassed at not knowing what kind of tree it is) has an extremely large wound on its back side.  The wound is nearly a foot wide, and nearly 4 feet long.  Due to the number of old stumps on my acreage, I suspect the damage was caused long ago by loggers (grrrr-r-r-r-r) cutting down a tree that raked across this one as it fell.  All the bark is gone, exposing a very large section of the interior wood of the tree, which over the 10 years I've been here, is evidencing increasingly drier wood and much deeper cracks in the exposed wood.  Also, there are a few 6"-8" deep  triangular shaped areas at its base with no bark, and I find quite worrisome, may have been caused by insects.  (I have and continue to treat for those.)  I have applied tree wound dressing numerous times, but it always wears off.  The Ag Extention here says it's better not to treat it at all, and you apparently also feel that way.  It is an amazing tree, the prettiest and tallest on my land, and it has "built" itself much wider around the affected area.  Maybe it's okay, even better off, left alone, but I worry so much that it's going to dry out and die.  Is there ANYTHING (latex paint?) I can coat that very large section with, that is safe for the healthy part of my tree?  Thank you!

Answer
The wound will heal by itself. Large wounds may never completely heal over. Any type of wound dressing (paint. tar etc.) will slow the healing down. If insect called a borer attacks the wound they will leave saw dust and then the area can be sprayed with an insecticide called Merit. This will kill any insect in the wound.  Decay fungi may get into the wound but this is normal and the worst they decay fungi could do is cause the tree to be hollow but this will not effect the overall health of the tree. I would do nothing but watch for signs of insect attack. Do not worry about the tree it will be fine.