Perennial ryegrass is a high yielding, high quality grass. Under grazing management, the best varieties are very persistent provided they are well fertilized and well managed. In cold areas, perennial ryegrass plays an important role in short term-production with high yields and quality. Perennial ryegrass is compatible in mixtures with white clover. It is suitable for cultivation in most types of soils except very wet land. Perennial ryegrass is available in early, intermediate and late heading types and as diploid and tetraploid.