Uniformitarian scientists have long been puzzled by an apparent dearth of trees, even in unglaciated areas, during the supposed 2.6 million years of the Pleistocene Epoch. Thick forests can take centuries to grow, and creation scientists estimate that the most likely duration of the post-Flood Ice Age was 700 years. Since the Genesis Flood killed every living tree in the pre-Flood world, and since thick forests normally take centuries to grow, this general absence of Ice Age trees could be evidence for the Creation Ice Age model. On the other hand, it may also present a challenge to the Creation model, as abundant precipitation early in the Ice Age would seem to favor rapid tree growth. Evidence for an absence of mature Ice Age forests seems especially strong in Europe and North America.