Use Cambistat for a Pin Oak
Three years ago during construction of my friend's house, the excavator dug within two feet of the pin oak. An arborist recommended a treatment of cambistat, to generate root growth after disturbance. Also recommended a reapplication in three years, now. The question is: Since the three years are up, does the tree need another cambistat treatment? I'm not sure if cambistat is a one time proposition or it actually needs to be reapplied. Note: The tree is doing well. They are very fond of this large tree and want to do everything we can to make sure it continues to live. Any advice you can provide would be greatly appreciated.
If your tree is putting out new shoot growth and is healthy another treatment is not recommended or necessary.