There is little doubt that the lowest costs of beef or milk production are achieved when the animals are grazed on pastures from which they obtain most or all of their sustenance. On the other hand the most expensive phase of cattle production is the winter period when stock are usually housed and must be hand-fed. The results from numerous investigations firmly support these assertions. In the large mixed farming area of the North-East of Scotland virtually no grazing is normally available from the middle or end of October until the beginning of May when normal grass growth has resumed.