Last year my Pistache had lost and yellowed leaves late in the summer after being in the location for probably 10 years. The trunk had the root flair covered. I had the flare exposed only to find significant defects at the base of the trunk. The arborist suggested that it be staked. It was my understanding that this was not a good idea. The tree did ok this year with no further loss, but no significant recovery. Following yesterday's Rita winds the tree now leans about 15-20 degrees. What next? Cut it down? stake it? Thanks

As long as the tree is still standing, this could be a good thing. I like the effect of trees growing at an angle. It adds interest. Staking is just not natural. I would not do it. One of the problems with staking trees is that they do not have strength in the root system to withstand high winds.

It is good that you uncovered the flare. If you had not, the tree might have come down. That is one of the problems with planting a tree too low, or letting dirt collect up on the trunk. Problems arising from the roots girdling around the trunk can eventually cause the tree to fall over when a strong enough wind comes along.

Where do you live? Having at least your general location in your profile enables people to better help you.