The use of a forage processor, which is fixed within the forage harvester and cracks the grains of whole-crop wheat (WCW) at harvest, has been shown to increase the digestibility of the starch component and improve the efficiency of forage utilisation in dairy cows (Jackson et al., 2002). This allows the wheat to be harvested over a much wider harvest window, although the optimum stage of maturity at which processed WCW should be cut is unclear. In addition, at the very high dry matter (DM) values that the forage processor allows WCW to now be harvested, the use of urea as a preservative may not be required. The objective of the current experiment was, therefore, to compare WCW harvested at different stages of maturity and investigate the effect of using a urea-based preservative on high DM processed WCW, on the performance of dairy cows.