How to care for large cedars

Asked September 18, 2019, 1:57 PM EDT

I bought my home in Columbia County a year ago and one of the attractions was a line of very tall evergreen trees along the property line (next to a neighbor's house). They are stunning and home to seemingly thousands of birds. In a matter of a few weeks this Summer, three or four of the trees (cedars, I think) turned brown from top to bottom, completely dead. I asked a tree care company to come out and they recommend removing the dead but said it was beetles and wood peckers and the others may also die shortly. He also recommended topping the other trees because they are “too tall for the environment they are in” My husband also thinks they should be topped but I hate that idea. Is tree topping recommended for cedars over 50 ft tall in a suburban-ish neighborhood? The lots nearby range from 1/2 acre to 3 acres. Are the remaining live cedars doomed anyway from the beetles? Should we plan to remove and replace them?

Columbia County Oregon

1 Response

I'm glad you contacted us because you are getting a lot of misinformation.

We have observed a lot of large western redcedars dying suddenly like this over the summer. We believe the cause to be prolonged stress from several successive years of hot and dry summers. Although that was not the case this summer, it often takes a year or more for trees to show signs of stress. Your trees fit the description of what we are seeing all around the area.

Woodpeckers do not kill trees. And if there were beetles present in these dead trees, they would not be the reason they died. Instead, they come in only when a tree is already dying from some other cause like drought stress. So as long as the other trees are healthy, they would not spread to the other trees. It is possible that you might see some other trees die next year, but it would not be because of something that moved from one tree to the next.

Finally, tree topping is NEVER recommended. It causes a lot of harm to the tree, including creating an opening where decay fungus and rots can be introduced. A 50' tree is perfectly fine growing in a large-lot suburban setting as you describe.

I recommend removing the dead trees if you wish to improve the aesthetics and/or if they would hit something should they fall. If you do not wish to pay for the removal, they can be left standing and you can be assured nothing will spread from them to other trees. In a couple of years, the dead foliage will fall off. Dead trees (called snags) make excellent wildlife habitat and since you enjoy the birds, you might want to keep them standing for this reason. Pileated woodpeckers love to create nesting cavities in old cedar trees.

Here are some references for you:
Why is my western redcedar dying?:

Many insects are mistaken for tree killers:

Why topping hurts trees: