American Sycamore: A Crown Fit for a King

Just north of the charming downtown district of Lebanon, OH, an area with well-known buildings and historical markers spanning over two centuries, a different kind of historical marker recently caught my eye. In the expansive front lawn of an elementary school building, I beheld two massive American sycamores towering over the manicured lawn.
As any good tree measurer would do, I pulled out my laser rangefinder and headed in the direction of the trees. While slowly approaching and becoming enveloped by the intermingled crowns of the wide-spreading trees, it became apparent that the crown spread on one of them was truly superlative. The tree closest to the school boasts a maximum crown spread of 145 feet, with an average crown spread of 134 feet – the largest crown spread of any species that I have personally measured.

What exactly is crown spread and how is it measured? From the American Forests Measuring Guidelines Handbook: “Crown spread is the horizontal separation of two points on opposite sides of the crown.” Imagine an outline of a tree’s crown projected downwards onto a horizontal plane. A line connecting the two points farthest away from each other represents the maximum spread. The simple 2-axis method can be used to find average spread by taking an additional spread measurement that is perpendicular to the maximum spread, and averaging the two measurements. The above-referenced American Forests handbook has excellent explanations of the 2-axis method and the more precise spoke method.

I’ve seen photographs and heard of other wide-spreading American sycamores scattered across the Eastern United States, but I didn’t have a full grasp of just how big the spreads can be. To find out, I reached out to fellow members of the Native Tree Society, the nation’s foremost collection of tree measuring experts. After seeing the measurements for some of the most famous American sycamores across the East, I’m beginning to think that the tree in Lebanon may even still yet have some room to grow! Here is a sampling of American sycamore spread measurements from the Native Tree Society. Some of these trees have experienced crown loss since the time of the measurement.

[table id=3 /]

It’s clear that the American sycamore, when given the chance, can attain great dimensions and truly has a crown fit for a king. Have you seen a wide-spreading American sycamore near you? If so, we’d love to hear about it!

American sycamore
American sycamore, Platanus occidentalis, in Lebanon, OH. Photo by Matt Markworth
American sycamore leaves
American sycamore leaves. Photo by Matt Markworth