A prairie is a plain of grassy land without many trees. If you're raising cattle, find some prairie land to let them roam around on.
Prairie means grassland, and comes from the French word for "meadow." While we might describe a single meadow, we usually use prairie to describe a type of countryside. In the United States, the natural state of the land between the Mississippi River and the Rocky Mountains is prairie, which is why there's so much farming there.