Arborvitae trees

Asked July 30, 2019, 2:44 PM EDT

My arborvitae have suddenly started having ‘burn’ appearances on branches. My neighbor called it something (not sure what) but says it will kill the tree(s) (grouping of them) quickly...which I have noticed... he cut down one of the trees the other day due to how much it had been affected. Please help with a suggestion .

Oakland County Michigan

1 Response

Hello,

Take a close look at the areas turning brown. This could be spider mites, scale, or a fungal issue. If the soil is very dry, this could be drought dieback, or a drowning issue if soil is soggy and never dries out.a recent spray of herbicide on another plant or to lawns may have drifted and caught some of the foliage- icheck for a pattern such as is the browning only on one side?

Here is a link with good close up pictures of some issues. Take a magnifying hand lens and compare your leaves-

https://apps.extension.umn.edu/garden/diagnose/plant/evergreen/arborvitae/patchyyellowtobrowndiscoloration.html

If nothing is apparent, send branch samples consisting of a woody branch section, green, yellowing, and brown leaves to https://pestid.msu.edu

The website has instructions and fee schedule. The lab can diagnose the branches and give you treatment options.

Another option is to hire a certified arborist, a professional who has taken training in care, diseases, pests and passed certification tests. He/she will come on site and give a complete diagnosis and a plant care plan. Find certified arborists by zip code here:

www.treesaregood.org

Thanks for using our service.