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The Dawes Arboretum in Newark, Ohio is one of two sites in my study, Secrest Arboretum & Wooster, Ohio being the other, with over 25 trees. In fact both have exactly 51 trees on site, more than doubling the total of any other site! But that is not even the most noteworthy accomplishment of the Dawes Arboretum. Along with John Kuser of the Cook College of Rutgers University, the Dawes Arboretum remedied the problem of Metasequoia inbreeding depression. This was a problem caused by all original Arnold Arboretum trees being genetically derived from very few, maybe even 1 tree in China.
The Dawes Arboretum in Newark, Ohio is about 30 minutes east of the Ohio capitol of Columbus. It is within the Eastern broadleaf oceanic forest, and is located on a fringe area between Hardiness Zones 5 and 6, meaning it is fairly temperate. The winds are average, precipitation is average, and the dominant soil order is Alfisols. The Dawes is a very well known arboretum, and has contributed significantly to the development of Metasequoias in the United States. It was founded in 1929 and currently holds 1,650 acres of plant collections, with a five mile auto-tour and eight miles of hiking trails. Additionally, the Dawes has a particularly advanced GIS system used to keep very accurate track of all their holdings. How many other arboretums can say that they have exactly 22,447 recorded plants in their database? The garden boasts an impressive conifer, holly, crab apple, witch hazel, viburnum, and spirea collection. While the Dawes features likely hundreds of Metasequoia trees growing both for show and for research/cultivation purposes across the grounds, none of the trees have grown very well here compared to other areas of Ohio. It is strange that Metasequoias have not grown well here, especially considering they grow well at the Secrest Arboretum in Wooster. This is unusual because the Secrest is closer to the cold winds of Lake Erie. This may be caused by differences in grounds, maintenance, and specific garden-related issues. In any event, the Dawes nonetheless features an impressive group of trees if not only because 51 of them were planted before 1975. Hundreds more were propagated through the collective efforts of the Dawes and John Kuser with the goal of increasing the genetic diversity of Metasequoias in the United States. Of the 51 trees, three were received from the Arnold Arboretum in 1950, and one is particularly impressive and stands out from the rest, at 76 feet tall with a base diameter of 43 inches. The height is not spectacular but it is a tree with a large base, notably larger than any other specimen at the Dawes by far. The other two Arnold originals did not fare as well, one 50 feet tall with a base diameter of 10 inches and the other 80 feet tall with a base diameter of 20 inches. |
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Another 47 trees were planted here in 1959 and 1960, all created from the first tree the Dawes received from the Arnold in 1950. This mother tree did not produce progeny as impressive. None of these 47 have a height over 65 feet and none have a base diameter of over 25 inches. In fact the average height is about 60 feet and the average base diameter is about 15 inches. Additionally they display uncharacteristic similarity in size, with no strange outliers in height or base diameter. The last of the 51 was received from the National Arboretum in 1964 and has not fared well, reaching a height of 40 feet with a base diameter of 20 inches. So unlike many other gardens, the Dawes successfully propagated new Metasequoias from an existing one, already setting a precedent that many gardens were unable to accomplish. Again, this propagation was unusual because Metasequoias in the US were unable to propagate new seeds because they all genetically derived from three Chinese trees. John Kuser of Rutgers University discovered this and explained it in a paper. For a detailed explanation of what Kuser did after he wrote this paper and how the Dawes Arboretum helped him, go from here to my Rutgers Gardens page. Kuser fixed this problem when he asked for and received genetically unique seeds from China. He germinated them and then shipped them to the Dawes where they were planted. The arboretum planted all of these seeds on the same day, in April of 1993. Over 340 young Metasequoias were planted. These are the only genetically complete collection of Metasequoias in the world besides Rutgers and China. Other gardens that received the seeds include Callaway Gardens, Princeton University, the Holden Arboretum, and the Arnold Arboretum, among others. Within a year, the trees were as a whole growing very well, with only a few that did not survive the winter. By 1999 the young trees were doing wonderfully. It is an amazing success story that ultimately will entail sending new genetic types of Metasequoias throughout the United States and back again to China. It is really reminiscent of the original Metasequoia diaspora fostered by the Arnold Arboretum in 1948, only this time, with potentially incredible results. Already, new varieties like “Ogon” and “Sheridan Spire” exist, all young trees that will someday exhibit tendencies perhaps quite different from the current array of Metasequoias in the United States. Who knows what this next generation may bring? Dawes Arboretum 7770 Jacksonville Road Newark, OH 43056 |
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