hay

Baled hay in a field in Oxfordshire, England. Farming removes many nutrients from ecosystems. In a natural ecosystem nutrients are recycled during leaf-fall. In farming systems, however, nutrients are removed during harvest. Some are consumed directly by people, whereas others - such as the hay here - are consumed by animals, which are then in turn consumed by people. The more intensive the farming system, the more nutrients are taken from the land.

Preserved grass used for winter livestock feed. The grass is cut and allowed to dry in the field before being removed for storage in a barn.

The optimum period for cutting is when the grass has just come into flower and contains most feed value. During the natural drying process, the moisture content is reduced from 70-80% down to a safe level of 20%. In normal weather conditions, this takes from two to five days, during which time the hay is turned by machine to ensure even drying. Hay is normally baled before removal from the field.

2.47 acres/1 hectare of grass can produce up to 7.3 tons/7.5 tonnes of hay.