Much research has been conducted on the effects of whole-crop wheat (WCW) on dairy cow intake, performance and apparent digestibility. Recently attention has focussed on more accurately predicting the nutritive value of WCW. By contrast, relatively little research has been conducted to examine the variation in the chemical composition of WCW within a clamp, and there is little information on the most suitable sampling protocol. The objective of the current experiment was to determine the variation in chemical composition within clamps of fermented WCW and high DM, urea-treated WCW to assist in producing guidelines for representative sampling.