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Great forests of redwood once flourished in many parts of the world. Since the discovery of redwood leaf impressions in France and the later discovery of fossil redwood cones in Switzerland by the great paleobotanist, Oswald Heer, fossil leaves, cones and wood of the redwood type have been found throughout most of the Northern Hemisphere (see map page 57). Although some of them differ from those of the living sequoias, all of them were assigned to the genus Sequoia. Some of the fossil cones are attached to elongated stalks on which there are no needles. It was not until 1941 that the Japanese paleobotanist, Shigeru Miki, presented the evidence for referring cones of this type to a new genus, to which he gave the name Metasequoia, or “dawn redwood.”
Then in February, 1946, came the startling announcement that the dawn redwood was still living. Tsang Wang, a Chinese forester, found the first one, the Discovery Tree, which is 64 inches in diameter and 98 feet high, among the rice paddies in a completely deforested valley near the village of Mo-tao-chi, more than a hundred miles northeast of Chungking in Szechuan Province. A second expedition, later in 1946, located 25 more trees, some over 7 feet in diameter and 100 feet high.
Dr. E. D. Merrill, director of the Arnold Arboretum of Harvard University, arranged for an expedition to collect seed for planting in as many places as possible, to insure continued survival of the species. Another expedition in March, 1948, headed by Dr. Ralph W. Chaney of the University of California, under the auspices of the Save-the-Redwoods League, made a further study, collected more specimens, and discovered several more small groves of the dawn redwood. Seeds have now been planted in numerous parks, arboreta, national forests and at several universities in the United States. Many of the seedlings, after only one year’s growth, are almost one foot high. A further guarantee of their continued preservation is the formation of a national park in China for their protection.
There are several characters by which the Metasequoia may be distinguished from the coast redwood, which it most nearly resembles. The most surprising of these characters is the deciduous habit of the dawn redwood, in striking contrast to the evergreen habit of the coast redwood which holds its leaves for 3 or 4 years. The branches of the dawn redwood are ascending, while those of the coast redwood come out horizontally and are turned down at their tips. A third character has to do with the ovulate cones; they are attached on long, naked stems, like those of certain American fossils and the ones described from Japan by Miki. A fourth character is the occurrence of the male cones on long spikes. Wholly unlike the corresponding structures of Sequoia, these staminate
Copyright photo courtesy of San Francisco Chronicle.
A twig of the dawn redwood, a “living fossil,” recently discovered in China.
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By a restudy of all available fossil specimens, Dr. Chaney, of the University of California, has been able to refer the fossil collections of China, eastern Europe and Canada to Metasequoia, the fossils of British Columbia, western Europe and the United States being of the Sequoia type, except along the
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