A resident in Derby, Kansas, noticed the strange phenomenon known as tree suds in her yard on Tuesday. She shared the below photos with Nexstar’s KSNW.
Misti Hobbs took these two photos Tuesday as rain moved across the area. As you can see, it seems like sudsy soap is seeping out of the tree.
Erik Draper writes for Ohio State University that tree suds are actually a fairly common phenomenon that generally happens after long periods without rain.
During those dry periods, particulates from the air, salts, and plant chemicals tend to accumulate on the surface of tree bark. Rainwater washes and mixes with the different salts, chemicals, and particulates which can contain acid. When the salts, acids, and rainwater combine, a chemical reaction occurs that forms a sort of rudimentary soap.
As the mixture flows down the surface of the bark, it encounters bumps, ridges, and other obstacles that slowly introduce pockets of air, creating bubbles that eventually pool at the base of the tree.
Draper says tree suds can form on any type of tree, anywhere in the world where conditions are right. The best trees, according to Pennsylvania’s Brandywine Conservancy, will have a large diameter and “plenty of deep bark ridges” — that means trees like oak, hickory, or poplar trees are more likely to have tree suds than beech or sycamore trees.
If you spot it on your tree, there’s no cause for concern. Tree suds pose no risk to you, your tree, or your pets.
It isn’t just trees that get soapy, either. You may see it on paved roads, Rebecca Roy, the manager of educational programming for Vermont State Parks, told New Hampshire Public Radio. The oils on the roadway can combine with dust in the area, and with the help of wheels stirring up the mixture, you could spot some bubbles.