Key factors for selecting alfalfa

Today’s alfalfa varieties boast greater yield potential, better disease resistance and improved forage quality. So how do you decide which variety to plant? Here are some key factors to keep in mind when comparing alfalfa variety to your alfalfa stand expectation.

Intended use

Most alfalfa is planted for harvest as hay/silage or grazing with plans to keep stands if they are productive. Special situations may require different variety selection criteria. When selecting or comparing alfalfa varieties, base your decisions on how you expect the alfalfa to perform.

Winterhardiness

This is a measure of the alfalfa plant’s ability to survive the winter without injury. It is measured on a scale of 1 to 6 with 1 being the hardiest and 6 being the least hardy. Winter-injured plants may survive the winter, but the buds formed in the fall for spring regrowth may be killed. These plants have fewer shoots for first cutting and produce a lower yield.

Fall dormancy

This is measured by determining how tall alfalfa grows in the month following a September 1 cutting. More dormant types will remain short and low yielding through the fall period no matter how good the growing conditions are. Less dormant varieties typically yield more in the fall, green up earlier in the spring and recover more quickly between cuttings. Plant breeders have finally broken the relationship between winterhardiness and fall dormancy. Until recently, obtaining higher yields meant selecting a variety with less dormancy and lower winterhardiness. Now the strategy should be to choose less dormant varieties that meet your winter survival requirement. These plants will green up earlier in the spring and recover more quickly between cuttings to give higher total season yields.

Forage quality

Many new varieties on the market have improved forage quality. Evaluate alfalfa varieties based on estimated digestibility, intake and relative forage quality compared to standard varieties.