When sheep are out in a field, they eat grass or hay. They can also be fed grains, such as corn, oats and soybeans. Sheep can also eat invasive plants, including privet and honeysuckle.
Sheep are ruminants, which means that they re-digest their food. Sheep do not chew their food very well, but it passes through the esophagus and down into the rumen. This part of the stomach ferments the food after it has been reduced to a smaller size. This process generally takes eight hours or more for mature sheep. Once the food is broken down and fermented, it passes into the true stomach, where digestion occurs, and into the large intestine for further fermentation.
Because sheep are able to eat a wide variety of foods, they are used as targeted grazers for landowners and entities that need an economical and environmentally-friendly way of managing invasive plant species and overgrown properties. Sheep feed on ivy and kudzu, and can stand on their hind legs to feed on taller plants. Sheep are able to work in areas that feature poison ivy and briars because of their thick wool. They are also able to graze on rocky, forested or steep properties on which using heavy machinery may not be practical.