| ||Dutch elm disease (DED) is a deadly disease that can affect any elm tree. Since its introduction from Europe in 1930, it has destroyed millions of American elm trees across North America. DED is prevalent in Manitoba, Saskatchewan and Montana. At present, Alberta has the largest DED-free American elm stands in the world. A total of 219,334 elms, worth $634 million dollars, grow in Alberta's urban areas. Alberta has been fortunate to remain DED free for many years however, in 1998 one elm tree in Wainwright was confirmed to have disease. The tree was immediately removed and burned. It is believed that firewood brought into the province was the source of infection. Alberta is still DED-free.
Healthy American elm
Dutch elm disease