COUNTY AG NEWS
One of the challenges for dairy producers is deciding when to harvest their first crop of alfalfa. This date will vary from year to year depending on the amount of warm weather received each spring.
Relative Feed Value (RFV) is an index used to compare the quality of forages relative to the feed value of full bloom alfalfa. RFV is used to compare similar forages for two important qualities how well it will be consumed and how well it will be digested.
Optimum alfalfa quality for dairy cows should be around 150 RFV. For animals such as steers, heifers or dry cows the quality may be lower. Producers need to look at RFV as a tool that can be used to determine when to harvest first crop alfalfa. Producers also need to realize that a tradeoff of quality versus yield occurs by harvesting earlier.
The yield for alfalfa will increase around 150 pounds each day at the time of bud or blossom development. Forage quality is significantly impacted by the amount of leaves in the forage. Alfalfa leaves by themselves have a RFV of around 400 compared to alfalfa stems, which have a RFV of 80-100.