![]() In the late 1990s, however, Ben LePage and Chris Williams, then working at the University of Pennsylvania, showed us three-dimensionally preserved Metasequoia fossils that they had collected from the Canadian islands of Ellesmere and Axel Heiberg, on the northwestern side of Greenland. Imprints are analogous to animal tracks, occurring when plant tissue remains pressed into sediments and subsequently decomposes, while compressions occur when the tissue becomes sandwiched between flattened layers of sedimentary rocks. Scientists (and museumgoers) usually encounter two types of plant fossils: either imprints or compressions. With Metasequoia, which boasts a long fossil record, the implications of this research are especially pronounced given that we can test hypotheses at the molecular level across an enormous timescale. Recent innovations with laboratory instruments, however, have made it possible for researchers, including ourselves, to extract valuable molecular information from so-called rocks. Traditional paleobotanical studies are comparative-drawing links between the anatomy of fossils and their living relatives-while molecular analyses of isotopes and biomolecules (such as lipids, carbohydrates, and lignin) are usually reserved for modern samples of freshly harvested material. Yet the rare discovery of fossils containing exquisitely preserved organic tissues and biomolecules, coupled with new molecular research techniques, has revealed just that. When botanists first learned about the living population more than seventy years ago, no one could have imagined that those plants would provide crucial clues for understanding more than one hundred million years of historic climate change-not to mention changes to come. 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. After the tree drops its foliage in fall, plant it in the garden.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. Water the plant with 2 inches of water each week for the rest of the season.When roots have developed, transplant the cutting into a 1-gallon nursery container filled with a mixture of equal parts loam, sand, and compost.It may take two or even three months for anchoring roots to develop. Test for roots after one month by tugging on the branch to see if roots are holding it in place.Placing the pot on a heated mat may speed up the rooting process. Place the pot in a sheltered outdoor area and keep the sand constantly moist.Insert the branch, cut side down, into the pot of sand, burying it to about 1/2 its length.Coat the cut end and the scraped area with acid rooting powder. ![]() Scrape off a segment of bark about 1/2-inch long and 1/4-inch wide near the cut end of the branch but take care not to damage the leaf node. Angle the cut end at 45-degrees, just below a leaf node. ![]() An ideal cutting will have a stem about 1/4-inch thick. Cut a 6-inch-long shoot from a side branch on the tree with a pruning saw.Run water through the container for five minutes to rinse it thoroughly.Fill a 1-gallon nursery container with sand up to within 2 inches of the top.The Spruce Home Improvement Review Board.
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