Young aspens often don't survive because of factors such as grazing elk, according to a study by Northern Arizona University ...

In the two years that have followed the fire, the aspen stands have regenerated new sprouts that have grown without competition from other tree species and are now too tall to be grazed by elk.

However, aspen also has the ability to send up new young shoots, or suckers, off the root system of an established tree, sometimes up to 30 metres away, if the tree is large.