Honeylocust is appearing sick

(Question)

Hello, We really need your help. We have a beautiful honeylocust Tree which appears to be sick this year. I have taken pictures and wonder if is developing some sort of canker. The ends of the branches are dying, and it appears to have been infected with Gypsy moth caterpillars. The tree is quite large to spray for moths, however when I took The picture I didn’t see caterpillars on the tree. Lastly we had some Renovations done on our house and there was heavy equipment that travelled In close proximity to the tree, (outside the drip line). I hope the root system has not become damaged. Please help me save this tree. Thank you for your help.

(Answer)

Hello – Thanks for sending along the photo of your beautiful Honeylocust.  While it’s impossible to see the actual damage from your photo, the overall appearance and your description sounds like a problem that has been reported in the London and Hamilton areas.  The problem reported was branch dieback with yellowing and browning foliage at various locations in the tree. Samples of the affected sections were tested and some evidence of a canker was detected.  However, the conclusion was that the primary cause was winter damage which then provided opportunity for the canker to take hold.  The advice is to prune out the affected branches and destroy them.  As you have quite a lot of yellowing in your tree, you may want the advice of an arborist before undertaking any serious pruning.  Landscape Ontario is the trade association for landscape professionals in Ontario. You can locate arborists in your area on their web site at the link below.  I hope your Honeylocust is soon back to good health.

https://landscapeontario.com