Arborvitae - One section is turning brown

Asked July 29, 2020, 11:45 PM EDT

Hello, I planted 6 arborvitaes this spring. I have one that recently has started to turn brown in one section. I have been trying to make sure they get watered, but not too much. I have tried to self diagnose by reading online, but have found myself becoming more confused.

I read about the different diseases and root rot as well as fungicides(copper vs multi-purpose). I plan to take a look at roots tomorrow to try to determine if it is root rot, but as this is my first time planting arborvitaes, I am not sure how easily I will be able to tell. I am including two pictures taken a day or two apart, to show the progression and a 3rd that is a closeup.

The weather has been very hot and humid for a couple of weeks, does that help promote diseases?

Thanks for any assistance,

Portage County Ohio

1 Response

We have several arbor vitae planted on our property, and have had some invasions by bagworm that we learned how to take care of. We never have had the situation I see in your photographs. I have located some research-based articles, links to which are below. I am hoping you may see something here that gives you some ideas to pursue. You may learn a great deal more if you are able to consult with a certified arborist, and may be able to find one by talking to a local nursery or greenhouse staff.

You may learn more by calling your county's OSU Extension Service office, at:

Portage County Office

705 Oakwood St., Suite 103
Ravenna, OH 44266
These offices are closed presently, but staff are monitoring phone messages and responding to them.
Thank you for your question. We wish you success.