Several reports have come in indicating varying levels of winterkill in alfalfa. For dairy producers, this is an unwelcome start to the late spring. University of Minnesota Extension provides recommendations on alternative forages to replace damaged alfalfa and feed livestock affordably.
Alfalfa winterkill may be caused by a combination of factors, including harsh and long winter conditions, plant stress due to drought and, possibly, over-harvesting during the previous summer. Reports have indicated that late cuttings in 2012, even before Sept. 1, resulted in very little regrowth; observations of late summer cuttings have been reminiscent of alfalfa cut in mid-October.
In March, alfalfa fields looked to be in decent shape. The damage appears to have occurred after the slight temperature warming in March followed by the slushy snow in April. Southern Minnesota locations have reported a considerable amount of winterkill.
Forage selection and seeding strategies
Producers already face high feed prices. The last two years of dry weather resulted in a shortage of feed, especially forage.
Key attributes of successful forage options are that they establish quickly, grow rapidly, and provide good yield and quality per acre. Experts have made many suggestions, including ryegrass, sorghum-sudan grass, BMR sudan grass, clover, wheat, barley, oats, peas and oats silage. Some producers decide to replace alfalfa acres with corn or soybeans.
Availability of seed may be a concern that dictates which forage option works best for each producer. Dan Undersander, University of Wisconsin, recommends simply drilling Italian ryegrass into the dead areas with no tillage. Tillage would disturb the field and delay seeding. Undersander recommends seeding 10 lbs. /acre (55 seeds/sq. ft.).
If producers decide to plow their alfalfa fields, they should consider long-term needs for cow diets and decide if they will select alternative forage or use those acres to plant other crops.
This is a great time to evaluate your options for storing forages to prevent shrink and increase efficiency of forage feeding. Lactating cow diets in 2013 may reflect alfalfa shortage because producers will likely be feeding greater than 50 percent of the dry matter diet as corn silage.
Consider forage conservation options such as restricted feeding of growing heifers and exploring alternative non-forage fiber sources, such as whole fuzzy cottonseed, soyhulls, corn gluten feed, beet pulp, and sweet corn silage. Try to maximize forage quality for high-producing cows, and avoid making decisions that save money in the short-term but cost money in the long term.
Finally, evaluate potential cull cows, including excessive numbers of replacement heifers, to reduce forage needs. As always, consistency within the nutrition program is always a positive. Make necessary changes gradually and work to minimize variation in nutrient supply to dairy cattle.