Forage research indicates that, although alfalfa is considered to have good cold temperature tolerance, minor frost damage may occur when plants are exposed to air temperatures slightly below freezing for several hours, and more severe damage will be seen when temperatures drop below 25°F for four or more hours.
SDSU Extension Agronomy Field Specialist
Also by Sara Bauder
Due to a difficult, wet harvest last fall and a challenging marketing situation, many producers in the region chose to store grains wetter and longer than typical. As a result, special care needs to be taken when storing these grains as the air temperature rises into the summer months.
Winter kill and general stand loss of alfalfa has specifically been of concern in many parts of South Dakota the last two years. Most observed alfalfa winter kill is due to low, wet or flooded areas where plants were suffocated and died over the winter.