Seed development in ryegrass, and in red and white clover

Summary Studies were made of the rate of development of the seeds of perennial and Italian ryegrass, and of red and white clover. Three developmental phases can be recognised; the first a period of rapid growth and constant high moisture percentage, lasting about 10 days from pollination, during which viability is nil; a second phase of 10–14 days, when growth is slower and percentage moisture falls steadily, with sudden acquisition of viability; and a final phase of 3–7 days in which dry weight is constant but moisture decreases markedly. The effect of harvesting during these three phases is discussed, and mention is made of features useful in identifying the developmental stages.