Grecian anemone, Anemone blanda

Has this garden species spread to the wild? USDA, which seems to be generous with its answers, includes Grecian anemone as an introduced species. Flora of North America, which tends in the other direction, says this sometimes spreads from gardens, but is not well and persistently established. There's a patch of this in woods southwest of here. The elderly lady that owned the farm said she was sure she had not planted them, and thought they had been there a long time. But a couple years later her son told me she had dementia, and probably just didn't remember if she planted them. So, wild or not? In any case it's clear that they are not well established, and that may be just as well. These plants can cause a contact rash like poison ivy! USDA says these have been introduced to KY, MI, OH, VA, and ON. Lenawee Co MI, 3/22/12. Buttercup family, Raninculaceae.