I have a Purple Robe Robinia that has a number of dead branches. I took a close look today and found that it has an area about a foot high by 6 inches wide on the trunk that has lost its bark and the underneath part is punky. Also, the branches above have longitudinal areas where the bark is gone. There are some new, small branches growing on these branches but there are a lot of bigger branches that are dead. The tree is about 9 years old.any thoughts about the problem?
I've been trying to post pictures but for some reason they are out of focus on this site, even though they are fine on my computer.