Darnel usually grows in the same production zones as wheat and was a serious weed of cultivation until modern sorting machinery enabled darnel seeds to be separated efficiently from seed wheat. The similarity between these two plants is so great that in some regions, darnel is referred to as "false wheat". It bears a close resemblance to wheat until the ear appears. The spikes of "L. temulentum" are more slender than those of wheat. The spikelets are oriented edgeways to the rachis and have only a single glume, while those of wheat are oriented with the flat side to the rachis and have two glumes. Wheat will appear brown when ripe, whereas darnel is black.