The following is a release from the University of Minnesota Extension --
ST. PAUL, Minn. (5/6/2013) -- An unusual amount of winter injury and winterkill of alfalfa stands occurred in south central and southern Minnesota. While reports do not represent a detailed analysis of where injury to alfalfa occurred across Minnesota, they suggest a need for producers to check on stands and evaluate them for potential winter injury. Several environmental factors likely interacted to stress alfalfa and cause winter damage, including:
- a very dry fall and early winter that may have prevented alfalfa from accumulating adequate root reserves to survive the unusually long dormant period
- periods during the winter without snow cover which typically provides insulation against low air temperatures
- ice sheeting due to snow melting and rainfall in January/February; and the long periods of snow cover and low temperature that prevented spring alfalfa regrowth when reserves were low
Further recommendations for producers are available by going to University of Minnesota Extension's Minnesota Crop News.
Source: David Nicolai, Extension educator in crops, U of M Extension Regional Center, Farmington, 651-480-7732, firstname.lastname@example.org
Article contributions: Dr. Dan Undersander, Department of Agronomy, University of Wisconsin