In working with various landscaping I am hoping some of you here have some tree experience. Below are some pictures of a "Valley Oak". These are a protected tree in my local area (central valley of CA) and are typically very hardy. This one was very healthy and actively growing when suddenly about 3 months ago we started noticing some bark issues around the base of the tree. As you can see from the below pictures the bark issues have progressed to the tree itself and the roots. We never see any bugs on this tree. I took these pictures today after having an arborist from the area come look at it. His comments were 1) the tree has a problem and 2) don't know what it is and 3) should probably take it out. I was thinking more along the lines of trying to fix the problem before it got any more serious, not remove the tree. Any suggestions? Or perhaps somewhere else on the web you could suggest I find tree help? More information - the tree does not get any supplemental watering. The bush to the right of it does get some water throughout our hot summer but nothing that really saturates the ground. The pictures show some moisture because I took them today after a full day of rain. Normally the soil is fairly dry. Thanks for any help.