Question
Jim!  Thanks so much for volunteering your time! I'm so glad to have found you.  My wife and I are buying a new house in Northern Virginia.  There are 3 very large (~200') Willow Oak trees in the back yard.  I noticed while we were looking around the yard that a couple of them (maybe all) had a section or two of bark hanging loose (2-4 sqft) or completely gone.  I'm wondering what may have caused this and how concerned I should be?  Will the trees need to be cut down?  Any info you can give would be appreciated!  Thanks!

Answer
Generally if the foliage of a tree is thick and green (healthy looking) the tree is ok. Any damge that effects the trunk and/or root system will show up as the foliage thinning and looking off-color. Sounds like there may have been some type of mechanical damage that knocked the bark loose. Usually willow oak has a tight bark even though as it ages the bark gets rougher. I would suggest you contact the Virginia Department of Forestry (state agency) their State Pest Specialist is Tim Tigner, [email protected]  or 434-977-1375 ext. 3360 and ask his advice and maybe he can get up there or have one of the Va County Foresters or an Urban Forester come out and take a look on the ground. Tim is in Charlottesville. Tim is my counterpart in Va. and a friend and you can tell him I recommended him.