Is cedar toxic to cats?Updated 2 months ago

All of the cedar provided with our catios is "Western red cedar." It is left untreated and completely natural - the only things we do to it are plane it, sand it, and cut it to length. This type of lumber was originally selected due to its enduring outdoor properties. Left untreated and outdoors, it can last 10+ years before needing to be replaced.

Apparently, Western red cedar is actually not part of the cedar tree family (Cedrus). It is part of the cypress family (Cupressaceae). https://www.britannica.com/plant/Western-red-cedar

Western red cedar = Thuja plicata (scientific name)

The Western red cedar—Thuja plicata, can cause adverse effects in cats but is less dangerous than the Eastern red cedar and white cedar (most toxic - but also not a true cedar). These trees are toxic due to the presence of phenols and terpenes. https://www.catster.com/guides/is-cedar-poisonous-to-cats/

The "thuja" species also includes the common shrub arborvitae (so technically, it would also be toxic to cats) and those are in many yards, seemingly without issue.

However, it seems it is toxic only if ingested (and probably in large quantities), but we could not find a verified source that states this specifically.

In our 20+ year history, we have always used Western red cedar boards and it has never been reported to us that a cat became ill (or worse) due to the cedar. In some places (unverified) it is stated that many cats will not chew on cedar/cypress because of the aroma it puts off. But that's not to say that no cat has ever chewed on parts of these plants before.