Wow, that was a quick reply! Looks like it may be Smilax ecirrhata, it is native to Michigan. Thanks jaynine for your help. This quote might explain why it disappeared: "Populations of this plant are threatened by the overpopulation of White-tailed Deer", from http://www.illinoiswildflowers.info/woodland/plants/up_carrionflw.html - there are lots of deer in this nature center. This post was edited by westmichiganflorafau on Wed, Jan 21, 15 at 7:40

Thank you both. It seems so late for Osmorhiza to be developing but that's probably what it is. I hadn't even thought of bellflower. I think you are both right.

Thanks for the feedback. After checking other photos and details for the plant I am sure you nailed it. In Michigan it is actually considered a Noxious weed and quite toxic to livestock, especially horses; in Europe it is considered an ornamental plant good for landscaping purposes so I guess I will still include it in my collection of wildflowers even though most people in Mich. might disagree.

Thank you both. I plan to start ripping them out tomorrow. Unfortunately, the prior owner of this home, and my neighbors to both sides, seemingly love invasive plants. I have more gout weed coming through my fence that my neighbor has said were placed purposefully. Both neighbors also have English ivy, honeysuckle vines and wild grape vines I’m constantly battling