Dawn redwood wasn't on the brink of extinction, it, along with the gingko, were thought to be extinct until pockets of them were discovered in remote Chinese forests at the turn of the last century. In Washington State at Vantage is a highway overlook and park called Ginkgo Petrified Forest State Park, and at one time it was thought that these were examples of an extinct tree. (This park has a lot of types of petrified wood and it also has great petroglyphs).

Metasequoia glyptostroboides is the scientific name of dawn redwood, and was one I loved for the way it rolled off my tongue when I learned about it in a college botany class. It was such a great story. I must have told my daughter about it, because as a fluke, when she was spending a semester abroad in Japan and had a ceramics class she made me a mug and spelled out the scientific name under the glaze around the base. (I tried planting one here at the house, but it got fried one summer, and I realized I'd set it too near to some overhead wires so would have had to trim it a lot if it had survived).

(Ginkgo were also brought to many places in the US after this discovery and it's a feature in many parks and arboretums.)