Land that is torn up by human action becomes alfreka (a Norse term) and whatever land spirits might be there would be disturbed. That would be linked to odd events and a sense of unease. These are not spirits of the human dead, but spirits of the land itself, which the old-time Ioways called wakanda (mysterious powers).
Wakanda which was were especially noted in the water, in the bluffs, and in odd places. Most of these were only "bad" if disturbed. But some were just dangerous all the time. Water spirits which sometimes drowned people were called in Ioway, ischexi (water panther), one of the wakanda piskunyi (bad spirit).
There are still some stories I've heard from people who were warned to keep away from the river, and even particular places in the river, because those places had a bad reputation, and a person may have drowned there, and it could happen again.
But this isn't just in the water, some places on the land could be disturbed and then become hostile. The old-time people usually made offerings at such places to keep things from happening, like tobacco or food. In the old days, they offered dogs, as substitutes for human lives. Some people have had better luck if damaged land is repaired, like through planting native plants and fruit trees.
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