While Eric and other colleagues were enjoying tropical sun, I went in the opposite direction for the holidays, where it was only as cold as -20C (-4F). My father took me to see this tree because of its unusual shape for an elm (seen best in the second photograph). It reminded him of some of the work of the Group of Seven, perhaps (and I’m guessing) Lismer’s A September Gale or Varley’s Stormy Weather.
Ulmus americana, or the American elm was often used as a street tree in the early to mid-20th century of North America. In addition to being very tolerant of air pollution and extremely hardy, its classic vase-shape is pleasing. “Was often used” because this species had little resistance to the introduction of the fungal Dutch elm disease (DED); an estimate by Alden M. Townsend, a USDA-ARS plant geneticist suggests only 1 in a hundred thousand trees before the introduction of the fungus were DED-tolerant. Upon infection, trees react by attempting to stop the spread of the fungus through blocking its xylem tissue (water-carrying cells) — effectively, self-starvation. Needless to say, the American elm declined in numbers precipitously, with an estimate of 77 million trees dead by 1980 from the introduction of DED in 1931.
Unlike the American chestnut, though, small- to mid-sized trees of Ulmus americana can still be easily found, in part due to its prolific seed production and ability to tolerate poor soils. Young trees often reach reproductive maturity before succumbing to DED, so the species survives. However, the tall, ancient trees (to 300 years old) of previous centuries are unlikely to be seen again until resistance to DED is established, either naturally or through selective plant-breeding.
A few civic governments have put in place programs to manage (stall?) the spread of Dutch elm disease, mainly by controlling the primary vector of the disease, the elm bark beetle. Two places in North America where elms still form a significant part of the urban landscape are Washington, D.C. and Winnipeg, Manitoba.
Mary Eleanor Wilkins Freeman in Six Trees:
here was not in the whole countryside another tree which could compare with him. He was matchless. Never a stranger passed the elm but stopped, and stared, and said or thought something about it. Even dull rustics looked, and had a momentary lapse from vacuity. The tree was compelling. He insisted upon recognition of his beauty and grace. Let one try to pass him unheeding and sunken in contemplation of his own little affairs, and lo! He would force himself out of the landscape, not only upon the eyes, but the very soul…