Restore bark on Chinese Pistache tree?

I live in Sacramento, CA. I planted a Chinese Pistache tree in my back yard about 6 years ago. There's always been areas of the trunk where the bark appeared very rough, some of which would fall away from the trunk, but it would grow back and the next year the condition would occur again a little higher up the trunk.

Last year it seemed to be a little worse and is now about 5 feet up the trunk and along some of the branches. I have more pictures but don't know if I can post them in this forum.

I decided that I'd planted the tree in a bad location (too small an area for what would eventually be a very large tree). Also, I installed 1-foot root barriers in a 4-foot diameter around the tree to control the roots when I planted it. If the bark condition was a result of any stress to the tree, it's probably due to the root barriers. With all this in mind, in mid-January I undertook a very arduos project to transplant the tree to my front yard, where it has plenty of room and no constraints on the roots. Aside from the continuing bark condition, the transplant appears to have been successful--the tree is leafing out fine and I've peeled small areas under the bark of a couple of limbs and all appears green.

My concern about the bark peeling away is compounded by the fact that the new location of the tree will get more afternoon sun, which in mid-summer gets pretty hot in Sacramento. Usually, a Chinese Pistache will handle full afternoon sun just fine. My concern now is that the areas where the bark is gone might get burned this summer and cause permanent damage to the tree.

I'd like any advice about how to protect the tree and possibly apply a product to help restore the bark loss. I'm considering spraying the exposed area with Cloud Cover or similar product to retain moisture in the tree. I've also read about a product called EnviroTree, but can't seem to find much information about it to determine if it would be helpful, or where to buy it. (Does anyone know where I can purchase EnviroTree in California? Prefer near Sacramento.)

I also purchased a white permeable wrap that's made to protect tree trunks from sunburn. I might wrap the exposed areas after applying one of these products, or maybe just use the wrap only. My other thought is to keep the exposed areas moist as much as possible by misting.


Thanks in advance for responding.

I do not recommend putting any sort of sealant on the trunk. That stuff will usually give you more problems. If the tree seems healthy and is leafing out normally, I wouldn't worry about this spot. As long as there is no sap being excreted and no deep cavity, this may just be a cell malformation and won't pose any problem to the rest of the tree. Any chance you can send me a photo? I'd like to take another look. You can email me at mkoch@vctree.com

Hope this helps,
Mitch

So myself and three certified arborists looked at the photos and our best guess is that there is nothing wrong with the tree. Pistache trees, as a defination (and you can look this up), do have exfoliating bark when they get more mature. The only thing I would suggest is not to rub any of it off. Doesn't look like you have any potential problem, just some discoloration from removing the bark by rubbing it. We'd say just leave it alone and the new bark will mature and be looking like it did last year.

Pistacia chinensis
Chinese PistacheForm: Oval to rounded. Unruly growth in youth.
Size: 30 to 35 feet tall and 20 to 35 feet wide.
Zone: 6 to 9.
Leaves: Deciduous. Dark green in the summer. Variable fall color from yellow to fire red.
Bark: Shallow furrows becoming scaly. Exfoliating bark that exposes a pink to orange bark.
Fruit: A cluster of showy red fruit.
Flowers: Non-descript.
Growth Rate: Medium to fast.
Description: Although somewhat awkward in its juvenile form, this tree develops into a handsome and tidy canopy with age. A highly adaptable tree that can withstand the harshest of
conditions. Fall color is variable but can be outstanding.