Valley Forge (elm cultivar)

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The American Elm (U. americana) cultivar Valley Forge is the most Dutch elm disease resistant of the American elms. Raised by the Maryland Agricultural Research Service, it was released to wholesale nurseries by the U. S. National Arboretum in 1995. Although also resistant to elm leaf beetle, like all other American Elm cultivars Valley Forge is susceptible to elm yellows. All examples included in 10-year trials at Atherton, California, to evaluate replacements for Californian elms lost to disease, were withdrawn after a combination of rapid growth and poor structure condemned the trees as likely to require more maintenance than most municipalities would find acceptable (Costello, 2004). However, the performance of the trees in that study may reflect in large measure the fact that they were grown in a southern climate with minimal weed competition. The Valley Forge elm seems to develop far fewer structural problems in temperate climates further north, where the rate of growth in any given season is much more moderate, as well as in meadows, where competing vegetation tends to keep excessively vigorous growth in check [1]. Although this cultivar requires regular attention to training and pruning in its early years, such training by some accounts is easy enough to accomplish by those who are committed.

1 Arboreta etc. accessions
- 1.1 North America
- 1.2 Europe
2 Nurseries
- 2.1 North America
- 2.2 Europe
3 Etymology
4 Synonymy
5 References
6 External links

[edit] Arboreta etc. accessions

[edit] North America

Arnold Arboretum, acc. no. 180-2003.
Bartlett Tree Experts [2] acc. nos. 2001-258, 2001-259, 2001-486, 2001-491, 2003-1010.
Brenton Arboretum, Dallas Center, Iowa. No details available.
Holden Arboretum, acc. nos. 2002-76, 2004-38, 2004-47.
Scott Arboretum, acc. no. 98-110
Smith College, acc. no. 36205.

[edit] Europe

None known.

[edit] Nurseries

[edit] North America

(Widely available)

[edit] Europe

None known.

[edit] Etymology

The Valley Forge elm was named for the site near Philadelphia where American soldiers spent the winter of 1777 during the War of Independence.

[edit] Synonymy

None.

[edit] 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. [3]
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.