ABSTRACT
Introduction Plants continue to grow during their whole life, and this spectacular growth is largely due to their continuously active stem cells and meristems. In extreme cases, this yields giant redwood trees that are hundreds of years old with active meristems or the trembling giant, a clonal colony of a single male quaking aspen. The necessary primary root and shoot meristems are established early in development – during embryogenesis – and remain active throughout the plant’s life. In addition, some meristems are established de novo and post-embryonically, such as during lateral root initiation, and these also contribute to the final plant size and shape.
