Although the calendar says spring has arrived, the hot topic of discussion by most farmers will probably get to the weather forecast faster than you can say, “A long, hard winter.” Many farmers may have already purchased their forage seed for spring planting based on rotations or the need for livestock feed. However, spending time to evaluate alfalfa varieties is a crucial decision that has a direct influence on the bottom line. In addition to yield, there are other valuable selection criteria that producers should consider when looking at their seed needs and planting intentions.
Forages are an integral part of agricultural systems and producer goals may include improving soil health and structure, providing wildlife and beneficial insect habitat, improving water retention and protecting water quality. The best seed varieties will differ across these different goals, so it’s a vital decision point in planning. Excluding fertility, it’s the decision where farmers can have the most influence, so they should carefully choose the best seed variety for optimum economic and environmental impact.
To select the right alfalfa variety to meet the goals of your system, the main areas to consider include:
- Length of time in the rotation
- Disease resistance
- Variety traits
Short-term or long-term stand life
Winterhardiness is the primary evaluation to determine whether a variety will survive in a long-term stand. A short-term stand in Michigan (three to four years) should have varieties that are at least moderately winter hardy. Winter hardiness is closely tied to the dormancy of the variety. Group 2 dormancy would be considered winter hardy and is more long-lived than a moderately winter hardy variety with a dormancy group rating of 3 or 4. Producers should realize that the number of cuttings is clearly related to the group dormancy rating. The higher the rating, the more cuttings will be possible along with reduced stand longevity.
Michigan State University Extension alfalfa variety trials show that the top producing varieties can yield as much as 142 percent of the check. The average of all varieties tested showed an increase of 111 percent of the check. As an example, in a high fertility environment, if the check variety yielded 5 tons per acre, the average of all other varieties would be over a half ton alfalfa more per year per acre. Given a current price range of $225-$250 per ton for high quality alfalfa, this would equal $130 per acre per year. This more than makes up for any price difference in seed between the highest and lowest yielding varieties.