The last photo–these are First Nations (I’d guess Stony Nakota) ceremonial “robes” or “flags” (the ‘ball’ part is what is full of tobacco). These may have been tied in that spot because folks did Hanblecya (“vision quest”) there, or perhaps some other Ceremony was completed and the flags were taken there for another significant reason. Whatever the case, that is a TON of robes and likely indicates that each year more have been added to the same spot therefore representing several years of prayers/ceremony; this would also be indicated by the differences in the amount of fading of the different colours of fabric. It’s a real good idea to give wide berth to these sacred sites when you come across them. I would have loved to have been with you.