While dairies in the western U.S. are feeding less alfalfa hay to dairy cows than 10 to 15 years ago, California has probably seen more of a decline than other states. One factor is the significant drop in alfalfa hay acres in California compared to other Western states, but similar to other states is the current situation of lower milk prices and a desire by dairies to reduce feed costs.
Historically, when dairy profitability returns there would be an increase in alfalfa hay usage, but that has not been the trend in California. According to the California Department of Food and Agriculture, alfalfa hay fed to milk cows in 2009 was 11.73 pounds per head per day and there has been a steady decline since the first quarter of 2018 at 7.14 pounds.
Indications are that alfalfa usage will continue to decline in California as by-product feeds such as almond hulls are displacing some alfalfa hay in milk cow rations. However, many dairies still feel there are benefits to having some alfalfa hay in milk cow rations.