Discoloration - incense cedar

Asked January 6, 2019, 9:07 PM EST

I've noticed my incense cedar has started to turn brown in some areas this winter. Should I be concerned or is this a natural winter change? See photos. It is also this brown color on the top. I think it's been there for about a year and a half and has been happy, but it's the first winter. Thanks!

Multnomah County Oregon urban forestry cedar

1 Response

Thank you for your question!
It looks like the discoloration is occurring on the new growth, near the tips of the branches, which is not part of natural winter dieoff and tells us that there is something else going on.
There is a disease called incense cedar branch canker that has been popping up in our area over the past few years. Look for sunken, discolored areas along the affected branches. Here is a short article that describes the symptoms:
http://blogs.oregonstate.edu/treetopics/2014/06/27/whats-causing-die-back-incense-cedar/
and more here:
https://pnwhandbooks.org/plantdisease/host-disease/cedar-incense-branch-canker

Local Extension Forestry agent Amy Grotta (Columbia, Washington, Yamhill Counties) shares: "The only way that we could definitively diagnose this would be to have a sample tested by our Plant Clinic (for a fee).I have never seen this kill trees outright, it just makes them look bad. Pruning out the lower dead branches and disposing of them will help to reduce the spread. The drought we are experiencing may also be predisposing the trees to disease, so you can hope for more rain this winter and then water the trees deeply as needed next summer."
For more information or if you'd like to bring in a sample to diagnose, there are knowledgeable and helpful Master Gardener volunteers at our local Extension offices: https://extension.oregonstate.edu/program/all/mg/local-programs

Thanks,

Rose