Cones ripen in early December and release their seeds in the late December and early January, followed by seed germination in April (information from Shen-Hou Fan, the former director of Lichuan Native Metasequoia Management Office). We suggest, therefore, that in North America Taxodium preempted the sites that could have been occupied by Metasequoia, eventually leading to its extirpation. But at the lower latitudes of the US Southeast, the photosynthetic system of Taxodium has the competitive edge. We previously showed that Metasequoia has the superior photosynthetic system for adapting to the weak, continuous light of the high latitudes. However, Taxodium, a genus not found in Asia, has the same specialized seedling establishment requirements as Metasequoia. The river systems of the western United States could have provided migratory routes for Metasequoia to the Southeast as climate cooled and land masses rose. We present the case that the ecological requirement of moist bare soil for seedling establishment constrains Metasequoia to regularly disturbed riparian zones. Metasequoia has completely disappeared in North America. Fossils from the Holocene are missing on both continents, yet Metasequoia survived, presumably in wet-site refugia along the Yangtze River, and survives today as relic populations in central China. In North America this genus survived at least through the Pliocene, and in Asia through the early Pleistocene. *Information from Michael A.Fossils of Metasequoia, beginning in the Cretaceous Period, have been found throughout the Northern Hemisphere. Native Range: eastern Szechuan and western Hupeh China Lower slightly lighter in color, raised midribīark: reddish brown when young>darker, fissured, and exfoliating with ageĬulture: moist, deep, well-drained soil full sun little to no pruning appears to tolerate very wet sites Leaves: opposite, deciduous, flattened, straight or slightly curved, 1/2", upper bright green, Metasequoia glyptostroboides Bibliography and Other Resources-coming soonįlower: monoecious male flowers are racemes or panicles up to a foot long, female flowers are solitaryįruit: pendulous cones, globose or cylindrical, 3/4 to 1 1/4", 14-28 scales, mature in 5-7 monthsīuds: 1/4" ovoid or ellipsoid, bud scales light reddish or yellowish brown, opposite They are fast-growing, so even though our specimen is small, we might live to see it reach impressive height. It's exciting to have one planted in Maxwell and I hope it does well. Before dropping its leaves, it can have incredible fall color, especially when lit up on a sunny day. See more resources at the bottom of the page.ĭawn Redwood is a massive tree, but it has a soft delicate texture. And don't miss Doug Hank's wonderfully obsessive site about his planting project in North Carolina. Check out the web site for the latest info including annual conference information. A quick overview on Wikipedia can get you started and the compilation of historic and contemporary articles published as "Metasequoia After Fifty Years" by the Arnold Arboretum's Arnoldia in 1998-1999 will give you the best history available. The story of the discovery of a handful of remnant trees in Hubei Province and subsequent explorations is one of the most fascinating tales in modern botany. The literature concerning Metasequoia glyptostroboides is vast and well worth exploring. With the reopening of China to botanists in the late 1970s, new seed sources were available to bring in fresh genetic material. The oldest Metasequoia in the country were all propagated from these seeds. In 1946, the Arnold Arboretum obtained seeds from China and distributed them throughout the country. Its rediscovery in a remote mountainous region of China in the early 1940s rocked the botanical world. Larix decidua (European Larch) | Taxodium distichum (Baldcypress) | Metasequoia glyptostroboides (Dawn Redwood)īack to Deciduous Conifer main page Metasequoia glyptostroboides (Dawn Redwood)Īn ancient tree dating back over 65 million years that once covered much of North America, the Dawn Redwood was thought to be long extinct.
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