Unless you're really into alfalfa sprouts, you're not going to run into much genetically modified alfalfa during the course of your day. But it is used to feed livestock, like these cows chowing down on a mix of alfalfa and hay.
Alfalfa, like many other crops, was genetically engineered to resist glyphosate, which is a chemical used to kill weeds, and got FDA approval in 2011.
Shortly after its approval, officials predicted that about 50% of alfalfa made in the US will be genetically modified, according to The Wall Street Journal.