@WendyEM Looking up Isodontia sp. (genus) seems likely some of the nests were 1M off the ground and i couldn't imagine how a caterpillar would be able to carry the grass up to the hole.
Could I clarify. Does the grass result from the logs sitting somewhere that the grass grew through it? Or does it appear like something carried it there? I am not convinced these are lepidopters. While not quite like this there is for example Isodontia sp. (genus)