It hangs from what is believed to be its original yoke, made from American elm. Frederick Childe Hassam is notable among painters who have depicted American Elm. Thousands of attempts to cross the American elm with the Siberian elm "U. pumila" failed. Tree species include willow, American elm, and sycamore. Other artificial hybridizations with American elm are rare, and now regarded with suspicion. The tree is allogamous and is most closely related to the American elm "U. americana". The narrow streets of Ladd's Addition are lined with American Elm trees. There is a notable grove of old-growth American elm trees in Manhattan's Central Park. There are several large American Elm trees in western Massachusetts. The American elm is highly susceptible to DED and elm yellows. There is a heritage-listed avenue of American Elm in Grant Crescent, Griffith, Australian Capital Territory. Slow-germinating American Elm will remain dormant until the second season. Sugar maple (Acer Saccharum); and Alsace Street&colon; American Elm (Ulmus Americana). The current United States national champion American elm tree is located in Iberville Parish, Louisiana.