Regarding tent caterpillars, if you know what the egg mass looks like, they are easily seen and peeled off the bark of the tree - assuming it is of a size that this can be easily accomplished (a shiny dark gray mass about the size of a quarter - round or elongated). I removed about 20 eggs masses from a neighbor's ornamental weeping cherry years ago when I happened to notice one while standing next to the tree. I don't believe the caterpillars do lasting harm to trees but young fruit trees could easily be checked in years when the caterpillars are in their peak cycles. Patti Gotz Roosevelt Neighborhood Seattle
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