AbstractDuring the development of plants of the field bean (Vicia fabaL.) there was a rapid increase in protein, lignocellulosic material and total dry matter during a period extending from anthesis to a date 8 weeks later. Over the subsequent 10 weeks there was a much smaller increase in total protein and other components. The most important change during this period was a movement of nitrogen into the seeds. Throughout the experiment the major part of the total lignocellulosic material was associated with the stalks. The effect of the exclusion of this part of the plant on the chemical composition of a whole‐crop harvest is discusse