Rather limited amounts of information are available, but it is recognized that cereals and their by-products, sugar beet pulp, straw and root crops are poor sources of vitamin E, with only about 2^20 mg vitamin E/kg DM. Storage, heat processing, grinding and the addition of acids or alkalis depress the content. Scottish Agricultural Colleges/Scottish Agricultural Research Institutes (SAC/SARI, 1982) quote contents (mg vitamin E/kg DM) of 12^300 for fresh grass (with only the one exceptionally low value of 12), 100^300 for grass silage, 100^250 for good-quality dried grass, 150^450 for kale, but only 4^20 for hay.Weiss (1998) found similar contents in America: 80^200 in fresh, green grass, but 20^80% lower amounts in silage and in hay. Harrison and colleagues (1984) considered that dry cows obtained 100^1500 mg vitamin E/day from pasture, this being 5^6 times more than from silage stored for 6 months.