I called a friend who I knew had a super-duper camera and she obliged by taking dozens of photos over the next two days to try to capture those "bubbles" as we were seeing them. We determined that they were a kind of sap and 3-4 days later they had dried up!
My guess is that the plant is either a gold dust croton or a close relative. Here's a google images photo of a group of them, though ours is singular. And here is the perfect photo of the spring "sap." Enjoy!
|The little sap bubbles. Photo by Jo Clarke.|