Photo 2. Plants from left to right: 1) dead plant with soft root 2) asymmetrical growth, likely will not survive 3) new spring buds growing after winter injury. Plant will likely survive but be slightly delayed 4) Healthy plant with firm root and vigorous growth. Photo courtesy of Dan Martens.
- Alfalfa stand assessment: Is this stand good enough to keep? - University of Minnesota
- Assessing Alfalfa Stand Condition in the Spring - University of Wisconsin
- Alfalfa stand assessment (video) - University of Wisconsin
If the alfalfa field has a substantial area affected, there are a number of considerations to be made. Before making the decision to keep, terminate, or supplement the stand, it is important to evaluate forage and animal inventory as well as the various cropping and replant options. Whether a field should be rotated out of alfalfa or affected areas seeded to a supplemental forage crop will vary by operation. Resources to assist in crop management decisions can be found here:
- Alfalfa assessment: Factors leading to winter injury - University of Minnesota
- Winter injury of alfalfa: Putting the pieces together for livestock producers - University of Minnesota
- Assessing alfalfa stands - University of Wisconsin
If alfalfa stands are thin or patchy and termination of the stand is not an option for your operation, there are a number of forage options to seed into winterkilled areas. Information on seeding into standing alfalfa can be found here:
- Seeding into an existing alfalfa stand - University of Wisconsin
Deciding how to manage a winterkilled or injured alfalfa field can be difficult and will add unexpected costs. However, walking fields, evaluating forage needs, considering options and making a plan now is critical to make a good decision for your farm. The resources provided will help you make the decision to keep or terminate the stand, seed supplemental forage, purchase additional forage, and/or plant new stands of alfalfa. The right answer for you will depend on your specific field and operation.
Resources related to alfalfa winter kill and winter injury, as well as other forage information can be found at the University of Minnesota Extension Forage website: