Return of the American Elm

Smith, C. A.

The American Elm, which had long been missing from city streets, is starting to make a comeback. Dutch elm disease continues to kill thousands of trees annually, but researchers have spent decades studying why some elms remain healthy while neighboring trees die of the disease. The most important research has been that of Alden "Denny" Townsend, whose wide-ranging investigations identified pure American elms that have a high tolerance for Dutch elm disease, meaning that even infected trees can recover without lasting damage. Townsend's 1995 release of the Valley Forge and the New Harmony elms to the nursery industry sparked much of today's revived interest in American elms. A later large-scale assessment of disease resistance revealed that the older cultivar, the Princeton American elm has a higher level of disease tolerance, which is especially fortunate for a tree originally cultivated for its remarkable horticultural characteristics.