by Bob Kitchell,
originally published in the February 20,1999, issue of the Weld County Past Times
In its prime, the American elm was the most widely planted shade tree in the United States. This vase-shaped tree with widely arcing trunk-like branches was ideal for a large shade tree.
Before the Europeans settled this country, various Indian tribes used to conduct business and draw up treaties under these trees. This practice continued after America was established. George Washington, William Penn and Abraham Lincoln, to name a few, made important decisions or signed bills under elms.
The early colonists, when clearing trees for their homestead, would many times spare an old majestic American elm to locate their house under. As the country grew, elms were planted along the street of most towns, especially in New England. When America moved westward, so did the custom of planting these trees.
Although the American elm’s native growing region was almost everywhere east of the Rocky Mountain states, it was planted throughout the country with the exception of the southwest desert regions and subtropical areas.
This tree had numerous pest and disease problems but nothing major. Americans were willing to overlook this because there was nothing like a street planted with American elms. The streets would become columned and arched like the aisles of a Gothic cathedral.
By the 1930s, this American classic was well established in Greeley. It, along with silver maples and green ash, made up nearly 75 percent of the cities tree population. American elm was a good tree for our region. Besides the shape, it was noted for being a tough tree that grew quickly, survived in extreme weather and tolerated road salt.
Then disaster struck. The American elm encountered a fungus (Graphium Ulmi) that it had no defense against. It became known as the Dutch elm disease and was spread by elm bark beetles. The fungus basically plunged up the tree’s circulation system and death was usually within a few years.
It was first detected in Europe and was accidentally spread by an imported log shipment to Ohio in 1931. The disease spread quickly and each passing decade saw millions of American elms die. There was no cure and trying to control the elm bark beetles who carried it was cost prohibitive for most cities.
Thousands of communities were horrified as they lost the majority of their trees. Many New England towns had more than 70 percent of their trees planted in elms. In the early 1960s, Syracuse, N.Y., lost 90 percent of its elm in three years.
The most recent figures report more than 77 million American elms have been lost to Dutch elm disease. Within a few decades almost all of the trees planted before the 1960s will be gone.
In Greeley there are still some elms around in the older parts of town like Glenmere Park and the University of Northern Colorado campus. They make up less than 5 percent of the city’s tree count today compared to nearly 30 percent in the 1930s.
One tree at 911 6th St. is actually the fifth-largest surviving American elm in the country. Its measurements are about half the size of what this tree was capable of back east. Most of Greeley’s elms are in declining stages also.
There may be hope for the future. The U.S. National Arboretum, after extensive research, has come up with two cultivars that are tolerant of Dutch elm disease. Valley Forge and New Harmony will be available for sale by next year.
There is still a lot of reluctance and skepticism as to whether these new cultivars will succeed in the long run. Only time will tell. One thing is for certain, the American elm will never reach the popularity it once had.
Arborists have learned not to plant any more than 10 percent of any tree species in their city plantings. This prevents a city from losing a high percentage of its shade trees to a pest or disease problem. This lesson was learned the hard way by many towns across the country with the American elm.