Prologue

What was the unique environmental envelope that allowed this ancient tree to survive only in South East China?

The Amazing Dawn Redwood (Metasequoia glyptostroboides) 

Dawn Redwood Trees
 Mount Street Gardens
Mayfair, London

In my opinion, the discovery that the Dawn Redwood had not gone extinct was the horticultural wonder of the 20th century.  A small stand of the genus Metasequoia was found in an isolated Chinese village of Mo-tao-chi in the Szechuan province E. D. Merrill (1948).  Previously only known from fossil evidence dating back 100 million years, Metasequoia glyptostroboides had been believed to have been extinct for 5 million years.  Fossils of Metasequoia glyptostroboides have been found as far north as (Svalbard) Spitzbergen, Norway on the Arctic Circle, evidence of a much warmer world during the Mesozoic Ben Le Page, et al. (2006).  There was once widespread northern hemisphere distribution of this beautiful tree but not surprisingly young saplings are very sensitive to frost so the Pleistocene would not have been kind to the Metasequoia. 

The discovery was made in 1946 by Professor Cheng of the Chinese National Central University. In 1947 seeds were collected by the Arnold Arboretum of Harvard University and dstributed among botanical gardens in America and Europe.  The seeds were fast-growing enough that a young Dawn Redwood stood 1.5 m tall at the time of  Queen Elizabeth II's coronation in 1952.

Although this tree has been cultivated successfully throughout Europe and the United States, it requires summer irrigation and a moist climate.  For this reason primarily, in nature the Dawn Redwood has just a few scattered stands in China and is classified by the World Conservation Union as 'critically endangered' due to intensive rice cultivation and the poor chances of regeneration in the wild. 

Cambridge University Botanic Garden



Dawn Redwood's ferny foliage of bright, light green in Spring,that turn russet-brown with tints of coppery pink in Autumn