I did notice that the bubbles have an oily irridescence and seemed to pool at points where bark funneled and suddenly stopped or, as on the red maple in the photo above, where a scar or branch dripped water to a lower spot on the tree. Seemed to also be at the base of larger trees with mature bark.
Ecological notes: First soaking rain in a long while. Felt really good to be out in the woods with the fresh smell of rain washing the trees clean. The warm weather combined with the rain and everything just exploded. Things had been becoming green and now the woods has this vibrant fullness to its green.
Where: Centennial Woods
Other notes: First kingfisher in Centennial Woods in 2 years. Beavers are going to town on the hemlocks - probably not much longer for CW.