a1 Forest Geneticist, Cory Arboretum of New York Botanical Garden, Millbrook, New York 12545, U.S.A.
Elms have long been important components of the forests and cities around the world. In the little-more-than-sixty years since it was first found in Europe in 1918, Dutch Elm Disease (DED) has killed millions of elms in Europe, Western Asia, and North America (Figs 6 & 7). The Far East is the only major area in the temperate zone of the northern hemisphere that has not had a DED problem. For this reason, and because many species that are native to the Far East are resistant to the Disease, it is thought that DED may have originated in the Orient.