... lettuce plant the flowers do not mature all at once, instead they mature sequentially. The expansion of the pappus from the beak of the seed, called feathering, signals seed cluster maturation. ... with leaves away from the ground, or if the leaves are lying prostrate on the ground. Head type. The degree of heading and tightness of the head can be evaluated at the time of vegetable harvest. ... approximately 50% of the flowers have feathered, the crop is swathed. After 3 or 4 days, the seed is harvested and threshed with a combine. Harvest should happen in the late morning, so that residual...