Despite there being one or two bags hanging on one twig, it was never established that bagworrms were the cause of most of his problem. For instance, from what I could see these were old carcasses tied on from last year. True, they may have been a source of newly hatched worms but the OP didn't say he saw any. For all the damage, there would have had to be many, highly visible active bagworms at this time in NW Ohio. For that matter, most of the bagworms around here were killed during the winter. In my city, I have only found a few survivors in very shelthered spots. Also, many leaves showed holes in the middle. In my experience, bagworm larvae only eat from the outside in. The unfortunate part of this thread is that the OP was PO and won't share with us what he found from his "local source." (If he found out anything.) And, as you say, that might have been helpful to others reading the thread.