Metasequoia glyptostroboides | Family: Cupressaceae

Submission: Ethan Baker and Ian Van Loo

Identification:

Leaves – Singly attached flat needles; about ⅔” long; linear; 2-ranked; deciduous

Twigs and Buds – Reddish-brown twigs, opposite lateral branchlets

Cone – About 1”; subglobose; peltate; usually disintegrating at maturity

Bark – Reddish-brown when young; darkens when mature and forms vertical, shredding strips

Silvics: The dawn redwood is native to China’s Sichuan and Hubei provinces where it is found in low-lying areas near streams and rivers, hence the local nickname “water fir”. A versatile and fast-growing species, it may be found as a common ornamental across North America, Europe, and Asia. It grows best on moist, well-drained sites with slightly acidic soil. Ample growing space and sunlight exposure allow for the development of its natural cone-like shape.

Natural History:

Previously thought to be long extinct, our knowledge of the Metasequoia genus was derived from fossil records dating back to the late Mesozoic Era over 100 million years ago. In the winter of 1941, Chinese forester Kan Duo noticed a few trees growing outside the village of Modaoqi. The local villagers believed the trees to be divine, and had placed a shrine at the base of the largest. The dawn redwood identity remained unknown until collected specimens reached the Memorial Institute of Biology in Beijing in 1946. Here, Dr. Xian-su Hu was able to make the pivotal connection between the samples and an original paper written by Japanese paleobotanist Shigeru Miki describing the first knowledge and characteristics of the Metasequoia genus. It was a living fossil!

Roughly 60 million years ago, the dawn redwood was one of the most widespread tree species across the Northern Hemisphere, but by the 20th century had been reduced to an estimated 1,500 individuals spread across the Shuishaba Valley due to usage as firewood and building material.  Conservation efforts have ensured the survival of this fascinating, ancient species. 

Much of the dawn redwood’s success can be attributed to then Harvard University Arnold Arboretum’s director Dr. Elmer Drew Merrill. After samples of the tree from China arrived in Boston in 1946, Merrill arranged for a seed collecting expedition to retrieve seeds for distribution to botanical gardens and arboretums around the world. There were multiple efforts through the 1940s to collect necessary samples and seeds from remaining trees to investigate and better understand these prehistoric organisms. Access to the remote village of Modaoqi required a multi-day steamboat journey, followed by a seventy-two mile hike up mountainous terrain. Luckily, these expeditions were successful in providing the necessary seeds for conservation efforts. Through the rest of the 20th century, dawn redwoods were planted across North America, Europe, and Asia. It was originally thought that the tree would not survive many of the drier and colder climates of the Northern Hemisphere, contrary to the Eastern Sichuan province of Central China. But the species has proven to not only survive, but thrive in various climatic conditions, similar to Ginkgo biloba. Since the 1940s, this species has made a significant comeback, having been reintroduced in various habitats and locations. There are few insects and diseases that affect the species, aside from possible foliage damage by Japanese beetles. Overall, it is a very resilient tree. Today, Metasequoia glyptostroboides can be found at sites around the world, most of which have not seen these trees for millions of years. 

References:

Feather S. 2022. I’m Not Dead, Just Dormant!. Penn State Extension.  

Shane, J. 2004. Dendrology Handbook, University of Vermont, Unpublished.

Sand S. October 1992. The Dawn Redwood – East and west cooperated to save this living fossil from extinction. American Horticulturist: 40-44.