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the initial phase of grain ripening. It begins after the flowering stage; for example, in cereal grains the milk stage occurs 12–16 days after flowering and continues for seven to 15 days; it precedes wax ripeness. During the milk stage the plants are still greenish in color; the bottoms of the stems turn yellow, and the lower leaves of grains yellow, dry out, and die. The grain remains green, and when it is crushed, a thick, milky white fluid containing about 50 percent water appears. During the milk stage the flow of plastic substances to the grain continues. Since the grain is undersized and the weight per 1,000 seeds is less than normal, the grain is not fully mature.