The interest in and usage of Whole Crop Silage (WCS) as feed for dairy cattle has been increasing, both in Norway and in other Northern European countries. Whole crops usually return high yields from one single cut and may contribute significant amounts of starch as well as fibre, and reduce the need of purchased feeds. However, many farmers have experienced not obtaining the targeted starch content in their WCS, and feeding experiments have so far demonstrated that increased DM intake when WCS is offered is not allways accompanied by increases in milk production. In this project, field experiments will be conducted in order to investigate whether low starch contents in WCS may be due to crop composition and structure and/or losses of kernels during harvest and baling. In cooperation with manufacturers and sellers of mowers and balers, low-cost modifications of the machinery that will prevent losses and ensure the necessary pre-ensiling processing, will be sought developed and compared with preservation of less processed WCS added an acid containing preservative. A digestibility trial with dairy cows will be conducted to investigate whether processing of late harvested WCS is crucial to avoid that the kernels passes undigested throughout the digestive tract. Finally, a small scale ensiling trial will be conducted to investigate whether pre-preservation kernel crushing have impact on starch contents in WCS. The final aim is to develop a knowledge platform for producing and processing high yields of WCS with appropriate nutritive value for dairy cows, and to deliver new data to NorFor for better prediction of the nutritive value and role of WCS in dairy (and beef) production. The project has its foundation in questions and ideas raised by farmers and the extension service, and the involvement of stakeholders at several stages will ensure an efficient and continuous flow of information into and out of the project.