A preliminary investigation by Marsh and Gibson (2004) indicated that cracked head-cut urea treated whole crop wheat could offer beef producers the opportunity to achieve high levels of animal performance and reduce feed costs per kg gain when compared to diets based on rolled barley for intensively fed beef cattle. The objective of this experiment was therefore to evaluate crop yield and beef cattle performance from winter wheat and winter barley crops harvested both conventionally and at the end of physiological grain fill (approx 70% dry matter), the latter being made into cracked head-cut urea treated whole crop.