A healthy, green stand of alfalfa begins with choosing an alfalfa variety. Here are four keys for finding top-shelf alfalfa genetics from Dan Wiersma, DuPont Pioneer livestock information manager.identify overall risk for the most common alfalfa diseases. The maximum score is 35 (5 points per disease). While no alfalfa variety offers 100 percent resistance to a disease, top-shelf alfalfa varieties provide resistance above 50 percent for most diseases tested.
1. Work with the best.
Deal with a reputable seed company that provides the best genetics and cares enough to help make those genetics succeed on your farm. Look for a company that does more than deliver seed: Find one that offers trustworthy information and helps evaluate new products to fit your farm. A trusted advisor can help find ways to cut costs and identify value-adding opportunities.
2. Build a complete package.
Select a disease-and-winter-hardiness package to reduce worries about weather and soil risks. Today's varieties feature improved alfalfa establishment and stand longevity. Breeding has focused on disease-resistant varieties, providing resistance to bacterial wilt, verticillium wilt, fusarium wilt, anthracnose, phytophothora and aphanomyces (race 1 and 2) root rots. Each variety is evaluated and characterized as either susceptible, low resistance, moderate resistance, resistant and highly resistant.
A Disease Resistance Index (DRI) helps identify overall risk for the most common alfalfa diseases. The maximum score is 35 (5 points per disease). While no alfalfa variety offers 100 percent resistance to a disease, top-shelf alfalfa varieties provide resistance above 50 percent for most diseases tested.
Also consider winter-hardiness. In northern climates, this trait is best defined as protection of the alfalfa crown against extreme cold exposure.
Other factors for an alfalfa package may include lodging issue (look for good standability), extended harvest window (look for a high-quality variety), potato leafhopper resistance and weed issues (consider a glyphosate-resistant variety).
3. Demand proven performance.
University yield trials and data from seed companies can help prove yield potential. Small differences in yield can drive big differences in the bottom line. A half-ton alfalfa yield difference is equivalent to a 20-bushel difference in corn.
Many universities conduct alfalfa-variety evaluation trials that provide insights into top-performing genetics. Look for varieties that consistently rise to the top of the tests across multiple years and locations. In addition, company data - which drives breeding programs - can help confirm performance and reliability.
4. Understand the bag tag.
Learn to read alfalfa seed tags. Seed-coating amounts can range as high as 35 percent to as low as 8 percent. Seed-germination rates may vary significantly. The cost of seeding an acre of alfalfa can differ dramatically based on seed-coating and germination rates alone.
Most university research verifies that optimum alfalfa stands can be established with or without heavy clay seed coatings. Clay or limestone-based seed coatings do not provide enhanced germination rates. For good stand establishment, use high-germination seed that features a seed-applied fungicide and nitrogen-fixing rhizobium bacteria.
Seed selection is just the first step toward a healthy, bountiful alfalfa crop a reality. Start with top-shelf genetics and strive for maximum seedling establishment, good weed and pest control, and management of soil pH and fertility needs.
This article was originally published in the February 2015 issue of Progressive Forage Grower, and is reproduced with their permission.