Cedars of the Thuja kind

"the branches appear flattened as if they had been ironed" (Rocky Mt Tree Finder)

During our recent tour of Pleistocene flood landscapes we were driving through the Clark Fork River canyon which 15,000 years ago contained on the order of a thousand feet of water before it drained in a flood of of immense proportions, when we were side-tracked by something very different -- trees.  In small print on the Montana highway map was the promise of “giant cedars”.  We couldn't resist and headed off to the Ross Creek Giant Cedar Grove, where we took a wonderful one-mile walk through shade and light.

These are western red cedars, Thuja plicata.  Scientific (Latin) names may seem pretentious but in this case they clearly are useful, for there are many kinds of “cedars” in the world.  They aren’t just different species either, but completely different genera (plural for genus).  In other words they aren’t even closely related.  Here are some examples:

True cedars belong to the genus Cedrus.  They’re native to the western Himalayas and the Mediterranean region.  Examples include Deodar cedar and the Cedars of Lebanon.

The red cedar we talk about in South Dakota actually is a juniper, Juniperus virginiana.  The wood made great fenceposts before steel ones arrived.

The white cedar of Australia, Melia azedarach, isn’t even a conifer.  It’s a member of the mahogany family.

Range of western red cedar, Thuja plicata.  Source.

Western red cedar is native to the Pacific Northwest, reaching its easternmost limit in northwest Montana.  It has always been important to humans because it’s so resistant to decay.  It was and still is used by indigenous peoples and is of major economic importance for the rest of us, but that’s beside the point.  These are impressive and charismatic trees in and of themselves, as we discovered.

Western red cedars are big.  The largest are second only to giant sequoias in volume.  The mature cedars of the Ross grove are "only" about 400 years old (vs. 800-1000 years for the most ancient) so they aren't all that large, but they sure seemed big to us.  Our Wyoming trees are pretty puny in comparison.

It took us forever to tour the Enchanted Red Cedar Forest as there was much to see and ponder.

Bases of mature trees often are gracefully buttressed.

Branch ends are distinctly flattened and fern-like, making western red cedars easy to recognize.

Closeup showing scale-like leaves.

A Tree-Hugger.

Ross Grove is accessible via a four-mile winding road.  It's well worth a visit.

For more about western red cedars, see the USDA Fire Effects Information System.