Stemflow on trees

I have twice seen a foamy “blob” at the base of willow trees which I had thought were caused by Spittlebugs. However, I have since learned that this is a phenomena called Stemflow. It occurs on trees after a good rain following a dry period. Water runs down the trunk of the tree and collects various substances as it flows. When it pools near the bottom it forms a foamy substance which has the appearance of light soap. I have gone back and reclassified my two observations from Spittlebugs and Froghoppers to the tree genus Willows, and also set a Tag to Stemflow. If one goes to Explore and then, under Filters, enters Stemflow, six observations currently are listed worldwide. Always learning. Here is a link to my latest observation of stemflow, which contains a link to my earlier observation:

Here is a link to an article I found helpful - there are more on the web if one searches for Stemflow on trees.


Surprisingly, no such observation field seems to exist. Neither does one for copal.

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