Mitotic reactivation of the terminal bud and cambium of white ash.

The first appearance of mitotic figures in reactivatinig buds of 1-year-old ash seedlings is in leaf primordia. The occurrence of mitotic figures then progresses sequentially to the procambial cells and finally to the cambium at the base of the bud. Milotic reactivation of the cambium in progressively more proximal regions of the stem is slow, proceeding at a maximal rate of 6 centimeters per day.