Sweet Gum Balls

Although I spend a lot of time in the woodlands, I am pretty inept when it comes to identifying trees. Sure, I know an oak from a maple from a pine, but ask me what type of oak it is and I’m clueless. Even more so when the deciduous tree isn’t an oak or a maple. One of my 2019 New Year’s resolutions is to correct this shortcoming and start learning how to identify the trees native to the mid-Atlantic region.

It is with this goal in mind that during a recent hike I spied these curious hard, spherical fruits lying on the ground. I had seen them in past, didn’t know what tree bore them, and decided to find out. Plus, they have such cool structures that I was certain would make an interesting photograph.

What are these oddities? They’re the seed pods of the Sweet Gum tree (Liquidambar styraciflua), a native to the mid-Atlantic, and found as far north as New York city. This is a large, tall tree - 75 ft tall in some cases - that produces triangular leaves that turn spectacular shades of red and orange in the autumn.

The Sweet Gum’s spiky “gum balls” hang conspicuously from the tree’s smaller branches, sometimes all winter. These woody balls are in fact compound seed capsules. Several internet sites report that the seeds contain a high concentration of shikimic acid, one of the main ingredients in the manufacture of Tamiflu, while others report of the sap of the Sweet Gum has antiseptic properties. Yes, the dried sap - the ‘gum’ - can be chewed, but it isn’t a bit sweet.

And a microbiological side note: Sweet Gums fix nitrogen, which I assume means they have nitrogen-fixing bacterial species in association with their roots, either as nodules or more loosely associated with the root rhizosphere, making the Sweet Gum my new favorite tree.

Oh, yes, the photograph is the result of a couple of dozen stacked macro photographs. LIghting was from a cheap, small LED flashlight. The reflection is due to black plexiglass. I hope you like it. I think it really shows how bizarre these seed pods are.

Best wishes,

Bob