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The American Elm cultivar American Liberty is in fact a group of six genetically distinct cultivars under a single name, although they are superficially similar. Promoted exclusively by the Elm Research Institute (ERI) [1] since 1983, these trees have been planted across the United States in numbers which that organization claims to be in excess of 250,000. The six clones which comprise this series vary considerably in their level of resistance to Dutch elm disease, and none is immune, but some evidence suggests that at least one of the six clones may have a fairly high degree of DED-resistance [2]. It is claimed, controversially, by ERI that fewer than 180 American Liberty elm trees have been known to succumb to DED since the planting began in the early 1980's. Binomial name Ulmus americana L. The American Elm Ulmus americana is a species of elm native to eastern North America, occurring from Nova Scotia west to southeast Saskatchewan, and south to Florida and central Texas. ...
This Osteospermum Pink Whirls is a successful cultivar. ...
Binomial name Ulmus americana L. The American Elm Ulmus americana is a species of elm native to eastern North America, occurring from Nova Scotia west to southeast Saskatchewan, and south to Florida and central Texas. ...
Branch death, or Flagging, at multiple locations in the crown of a diseased elm. ...
The Liberty elm is reportedly suitable for street planting, being tolerant of de-icing salts and air pollution. However, examples included in 10-year trials at Atherton, California to evaluate replacements for Californian elms lost to disease did not perform well. With careful pruning they assumed the typical American Elm form and grew very rapidly; however, they proved vulnerable to disease, wind damage in winter, and high levels of injury from elm leaf beetles. Accordingly, the cultivar was deemed "highly questionable as a replacement" (Costello, 2004). Moreover, the American Liberty elms were noted as being highly susceptible to elm yellows (phloem necrosis) in New York (Sinclair et al., 1994). Examples tested by research scientists at the United States National Arboretum in the 1992-1993 also failed to perform well [3]; but unfortunately, it has never been clear which of the six clones were represented in the tests, so the results remain largely inconclusive. The American Liberty elm is reputedly "extremely expensive" to buy, particularly in the larger sizes (Giblin & Gillman, 2006). Atherton is a town in San Mateo County, California, United States. ...
Official language(s) English Capital Sacramento Largest city Los Angeles Area Ranked 3rd - Total 158,302 sq mi (410,000 km²) - Width 250 miles (400 km) - Length 770 miles (1,240 km) - % water 4. ...
NY redirects here. ...
The United States National Arboretum is an arboretum in Washington D.C., operated by the United States Department of Agriculture. ...
Arboreta etc. accessions
North America The Dominion Arboretum is an arboretum located in the Central Experimental Farm in Ottawa, Ontario, Canada. ...
The Holden Arboretum, in Kirtland, Ohio, USA, is one of largest arboretums and botanical gardens in the United States, with over 3,400 acres (14 km²), 600 acres (2. ...
Scott Arboretum (357 acres) is an arboretum located across the campus of Swarthmore College, 500 College Avenue, Swarthmore, Pennsylvania. ...
Europe None known.
Nurseries
North America (Widely available)
Europe None known.
References - Costello, L. R. (2004). A 10 -year evaluation of the performance of four elm cultivars in California, U. S. Journal of Arboriculture, March 2004. [5]
- Giblin, C. P. & Gillman, J. H. (2006). Elms for the Twin Cities: A Guide for Selection and Maintenance. University of Minnesota.
- Sinclair, W. A., Griffiths, H. G., & Lee, I-M., Journal of Arboriculture. 20: 176-189, 1994.
- Townsend, A. M., Bentz, S. E., and Douglass L. W. (2005). Evaluation of 19 American Elm Clones for Tolerance to Dutch Elm Disease. Journal of Environmental Horticulture, March 2005, Horticultural Research Institute, Washington, D.C.
- Footnote About the Liberty Elms
1994 (MCMXCIV) was a common year starting on Saturday of the Gregorian calendar, and was designated as the International Year of the Family and the International Year of the Sport and the Olympic Ideal by United Nations. ...
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