The choice of harvest date for leys is one of the most important factors affecting the size and quality of the harvest. An early harvest gives a high nutritive value while a late harvest gives larger quantity. Today?s aim to produce high nutritive leys gives early harvest dates both in primary growth and regrowth in northern part of Sweden. The consequence is a growth in the autumn, a "third harvest".The aim of this master thesis was to study the effects of different harvesting systems and their effect on size, feed quality, wintering and economy for conditions in the northern part of Sweden.