Question
We have three of these plants in our garden one at 10feet one at 13 feet one at 15 feet tall . the tallest has started to look wilted at the top and the bark is cracking and breaking away on the trunk . is this a desease or just old age  . My wife loves these plants so I do not want to lose them all , hope you can help graham

Answer
Graham,

I would suspect it is old age or maybe even some frost.I do not believe that it is a disease. These plants anr not subject to any diseases other than overwatering. If it has been too wet you may need to pot them up in very sandy soil to keep them dryer for the next year.  Cut the top off below the damage. That will cause the trunk to branch out in 2 or 3 places lower on the trunk and send out new growth.

On the 13 foot tall one I would suggest that if it does not branch out at all in the spring you should cut the top off of it and dip that in rooting hormone then plant it in another spot in the garden. It will then grow a whole new plant and the plant you cut it off of will send out new side shoots and grow new branches to make it a much prettier plant.

You can do the same thinng to the 10 foot tall one if you would like to and you will have an entire forest. Good luck.

Darlene