Grass Carp is an Asian Carp. Possessing one, knowingly or un-knowingly in MI is a 5 year Felony, 1/4 Mil fine, plus reparations to the state to eradicate them.
Question 2cat about that one!
When I was listed as a grass carp supplier in Indiana a couple of years ago I had a lady from Michigan that wanted to buy them. I told her they were illegal in Michigan. She said she knew but didn't care.

I said no way no how! For all I know it may have been a set up anyway.
I do seriously question why Michigan won't allow triploid grass carp in private ponds. Apparently your DNR is concerned they would eliminate natural beneficial macorphytes if they got into natural waters right? But at the same time we had a retired DNR official at an aquaculture meeting tell us they are worthless at eliminating macrophytes from ponds. Unless I'm missing something it appears they are trying to have it both ways. I remember him also saying their digestive tract is so short they poop out whatever they east immediately. Funny the picture Catmandoo posted of the intestines of one seemed to be the longest digestive tract I've ever seen.