I've been using the silly string comp because that's the closest thing it resembles, but maybe now I do need to quiz a neighbor at the end of the road now you mention the possibility it's not naturally occurring. We had a big blow that day. Saturday before, they had a big birthday party for their grandkid. Some windblown party favor from their property???It could be that someone has pranked you or it could be the beginning of the zombie apocalypse.
I am 99.9% it has not been seen on this forum for the fifteen years we have been here