American elm

A tall majestic tree, the American elm was often used in large, open spaces and to line streets, until Dutch elm disease began to take its toll. Since that time, this tree has become an economic burden, with a few thousand trees having to be cut down in Montreal every year. As this disease is incurable at the moment, use of this species is inadvisable, especially since there is no truly effective preventive treatment. Some cultivars, certain of them more resistant to the ailment, are derived from this species.