The United States are a nation of immigrants. There have been several instances where German Wischhoffs and Wischoffs have emigrated to the United States, mostly in the second half of the 19th century. 

One destination was Dane county in Wisconsin, where descendants can still be found and which was a popular destination for German immigrants, the same as Michigan was for Dutch immigrants. This line was started by Herman Peter Christoph Wischhoff (13 December 1850 - 9 February 1904), who emigrated from probably Hannover in Germany to New York City in 1867. From there he continued to Chicago, where he stayed for a few years as shoemaker before he moved on to Reedsburg, Wisconsin. Nice detail is that among my own ancestors there are also some shoemakers in that period. In Reedsburg Herman married Elisabeth Halbersleben, herself the daughter of German immigrants, in 1874. During the marriage twelve children were born, among them six boys. Two of them followed in their father's footsteps and became shoemakers. Descendants from this line are only partially known to me at this time.

I have been able to find many Wischhoffs, Wischoffs, Wischhofs, and Wischofs on public databases on the Internet (e.g. Social Security Death Index, Cemetery Records). Unfortunately, the information is incomplete and there are often no family connections. I therefore have to rely on family members in the U.S. to help me put the data into perspective.