It's a hay crop similar to clover. It's high in protein and fiber and it's fairly easy to grow. Since it restores nitrogen to the soil, many farmers plant it in rotation with their other crops.

Farmers cut the alfalfa then gather it together into bales, usually either gigantic round bales about 5 feet across and weighing over 1000 pounds (used for feeding cattle) or into "square" bales about a foot high, 1-1/2 feet wide and 3 feet long and weighing about 50 pounds. It can also be compacted into cubes about an inch square, or made into small pellets (most often fed to rabbits and other small animals).

During the spring, summer and fall, our sheep and goats mostly graze on the lawn, which is grass, clover, speedwell, dandelion, and various other plants. During the winter, the lawn turns brown so we feed them alfalfa, sugar beet pulp, corn, oats, sorghum and a wee bit of molasses.

Humans can eat alfalfa too in the form of alfalfa sprouts.

Mature alfalfa is very high in fiber and would probably be unpleasant to eat. It would be, quite literally, like eating hay.