University of Minnesota (U of M) Extension educators have pulled together information and resources to assess and deal with alfalfa winterkill.
As in Wisconsin, farmers in southern Minnesota are finding large areas of winterkill this spring.
"Reports of winter injury and winterkill of alfalfa continue to intensify across parts of southern Minnesota," says Jim Salfer, a U of M Extension dairy specialist. "As a result, livestock producers will need to carefully consider short and long-term inventory needs and then manage the damaged alfalfa to get as much productivity as possible."
You can find the additional information here.