glyptostroboides, is known as the dawn redwood and is now restricted to a small population in south-central China, around forty-two hundred miles (sixty-eight hundred kilometers) south of this historic distribution. The single remaining species of this genus, M. Fossil records reveal that an extensive forest flourished throughout the early Cenozoic, when the canopy was predominated by Metasequoia and other deciduous conifers. When planted on a good site, the young trees may exceed 130 feet in height, by the time they are 100 years of age.Around forty-five million years ago, the Arctic was ice free, scarcely the expanse of lichen-encrusted rock and glaciers that we see there today. The trees exhibit remarkably different growth habits when used as an ornamental, which probably relate to differences in growing conditions, rather than genetic diversity.ĭwarf redwoods are incredibly fast-growing trees. They grow readily from cuttings, which has helped increase their appeal and hasten their spread throughout the world’s gardens and parks. Nevertheless, the trees have been cultivated and planted in several locations around the globe.
Accordingly, they are not used as a commercial timber species. A product of their long history of isolation, this low genetic diversity may lead to the proliferation of undesirable traits.ĭesignated as “Endangered” by the IUCN Redlist of Threatened Species, all wild-growing dwarf redwoods are protected in China. Another challenge facing conservationists is the relatively low genetic diversity found within living specimens. Trees that grow in places where the local citizens rely on coal for heat often shed their leaves earlier and produce less fruit than those trees that grow in undisturbed areas. While conservation programs are in place, the excessive pollution associated with the use of coal is threatening many naturally growing populations.
Many of the remaining trees likely grew alongside ancient floodplains.īecause these trees only grow in a small geographic area, they are considered an endangered species. Although the exact cause of their decline is unknown, habitat alteration – such as the conversion of large tracts of land from forest to agricultural fields – was likely an important factor.
Scientists believe that these trees were once quite widespread throughout the Northern Hemisphere. This has led many to call the tree a “living fossil.” Interestingly, the fossilized trees were almost identical to the modern species, meaning that these trees have changed very little over the last 65 million years. However, a few years later, conservationists working in southwestern China found several living specimens. In 1941, paleobotanists identified dwarf redwoods fossils, but they were thought to be extinct. However, you can distinguish between the two by noting the leaf arrangement: Dwarf redwood leaves are arranged oppositely, while those of bald cypresses are arranged in alternate fashion. Both species are most common in riparian or flood plain habitats. The shape of their leaves and tendency to form wide, buttressed trunks (the trunks of some specimens exceed 15 feet in diameter), causes some to mistake these trees for bald cypresses (Taxodium distichum). The leaves of dwarf redwoods are bright green in the spring and summer, but they turn yellow, red or orange in the autumn in the winter, the trees appear as majestic skeletons, devoid of leaves. Unlike their taller cousins, who keep their leaves all year long, dwarf redwoods are deciduous trees, which shed their leaves in the winter.
Some botanists even contend that the dwarf redwood is the direct ancestor of the coastal redwood.Īlthough smaller than the other two types of redwood, the term “dwarf” is somewhat misleading, as these trees may reach 200 feet in height. The sole living species of its genus, dwarf redwoods are very attractive conifers, who are quite similar to coastal redwoods (Sequoia sempervirens). The dwarf or dawn redwood (Metasequoia glyptostroboides) is one of three species that bears the redwood moniker.
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