Winter Injury in Alfalfa: Assessment and Management

Snow cover Adequate winter snow cover protects alfalfa plants from prevailing air temperatures and is particularly important during late winter and early spring, when plants may be exposed to wide temperature fluctuations above and below freezing. Sub-freezing temperatures during late spring may cause injury if plants have developed some vegetative growth. Plants will have less cold resistance because of exposure to warmer temperatures. Their carbohydrate reserves may be so low that they are unable to reharden if exposed to a drop in temperature. By this time, hardiness may be greatly reduced or lacking.