Tetraploid cultivars have a slightly higher digestibility than diploid cultivars .
Because of its high quality, the primary use of perennial forage-type ryegrass in the U.S. is for lactating dairy cows on pasture. It is suitable for all classes of livestock, especially those with high nutrient requirements such as young growing animals. Silage Perennial ryegrass often is harvested for silage . It makes up a considerable portion of dairy quality grass silage in many parts of the world. As with all forage species, silage quality of perennial ryegrass is influenced greatly by maturity stage .