A reader contacted me recently about her very old (and very beautiful) American elm tree. The tree, she noted, had a circumference of 17 feet and was believed by some in the neighborhood to be about 240 years old. Would I like to take pictures of it? You bet!
The homeowner told me she was having the tree evaluated by an arborist because the house was being sold and the new owners thought they might need to remove the tree because of its age. I met certified arborist Keith Curtis of Shadywood Tree Experts and Landscaping at the property, just after he had analyzed the tree.
The good news: The tree seems to be in good health, though it has the marks and scars of any living thing that has been on the Earth a long time. It’s age, however, is a bit of a mystery, and it provides an interesting insight into trees and how they grow and age.
Keith measured the tree’s diameter 4 1/2 feet from the ground, the so called diameter at breast height (DBH), which is the international standard for measuring a tree’s diameter and estimating age. At that height, the elm had a diameter of 66 inches. If you figure a growth rate of one-half inch per year, the tree would then be in the 130-year-old range, so it could have been planted in the 1880s. The location of the tree just in the backyard gave Keith the impression that it also could have been planted when the house was built, which thanks to this terrific data base of building permits at the Hennepin County Library, I discovered was in 1923 or 1924. So, that would make it less than 100 years old.
But, as Keith told me, this is one BIG tree. He said he often gets told by homeowners that they have a big tree, but it’s really not that big. (He’s been looking at trees more than 20 years, so he knows.) This one is BIG. (The photo at the bottom of the post shows it best.) So, could it be 240 years old? It could be. It could also be much more than that, he said—like twice that much. But other than cutting it down and counting the growth rings there is no way to know for sure.
Surviving Dutch Elm
The other thing that is interesting about the tree is that it is there at all. In the 1960s, most of the elm trees in the Twin Cities were destroyed by Dutch elm disease. A few survived, perhaps due to good genetics and maybe the right location. In the past 20 years, many surviving elms have been treated to prevent the disease, Keith noted. The house next door to the big elm also has a large, old elm — about half or less the size of this one — but still very big. So maybe they were just in the right spot.
That’s all beyond my pay grade, but whatever its age, you can’t help but wonder what changes in weather and environment and surroundings this tree has endured. It’s a monument to the resilience of plants.