American Elm

Ulmus Americana

by John Brouwer

The classic picture of a southern Ontario town up until the 1960’s had elm trees on both sides of the street providing cathedral-like shade. The mature elm trees’ vase-like shape provided large open areas at street and house level with the upper branches meeting over the middle of the street. Every town has an Elm Street reminiscent of that era.

The picture changed in the late 1960”s when Dutch Elm disease arrived in North America, spread throughout, and killed most of our elm trees by the mid 1980s. Like most street names, Elm Street now refers to what was destroyed.

Except for Winnipeg. In Winnipeg in the late 1950’s city officials wanted to remove a majestic elm to make way for a new street. Outraged women locked arms around the tree in protest. The city backed down and the tree was saved. That spirit lead to the Coalition to Save the Elms which has been successful in saving most of the city’s 1,700 elms by working with the city and province in leading edge, Dutch elm disease control.

Dutch elm disease is a fungus which plugs up the tree’s vascular system killing mature trees within a few years of infection. The fungus is carried from tree to tree by the elm bark beetle. Control involves controlling the spread of the beetle and treating the fungus annually as a tree’s vascular system is renewed every year.

One of southern Ontario’s largest elms was known as the Sauble elm growing beside the Sauble River between Hepworth and Sauble Beach. This tree had a circumference of 25 feet and a height of 140 feet. The local tradition suggested that this tree survived the logging crews as it was too big to be cut with hand cross cut saws and was too big to dragged to a lumber yard. The tree was infected by Dutch elm disease in 1967 and succumbed a few years later. When it was cut down, a ring count proved that the tree germinated in 1701.

Elm developed 40 million years ago. It is intertwined with human history. Romans used elm to hold up their grape vines.

If that fair elm alone should stand, 
No grapes would glow with gold and tempt the hand, 
Or if that vine without her elm should grow, 
T'would creep, a poor neglected shrub below.” Ovid (43BC-17AD)

The Iroquois used elm bark to make canoes, rope, utensils, and roofing materials.

In times of scarcity elm bark and leaves became famine food.

Elm wood is cross-grained, making it tough and very hard to split. As a result it was used in wheel hubs and industrial machinery where toughness was needed. Today elm continues to be used for flooring, furniture, hockey sticks, musical instruments, boat frames and in other ways where toughness and durability is required.

Because elm was very difficult to cut down, farmers tended to leave elm trees so one can occasionally see solitary elms in open fields. Their isolation has protected them from disease.

Mushroom hunters have an affinity for Dutch elm disease. Dying elms foster morels so mushroom hunters look for groves of dead elms to find this spring delicacy.

Much research has been and continues to be done to return elms to Elm Street. Over the last decades selective breeding has found cultivars which exhibit resistance to Dutch elm disease. An elm has been planted alongside the exit path at the west end of the co-op. Only time will tell if this tree will be resistant and develop the vase-like spreading crown which used to be characteristic of small town Ontario.

October 2009