When a fire burns through an area, one of the first plants to reestablish is the aspen tree. This is because aspens reproduce clonally, meaning new saplings sprout from the underground root system of adult trees.
Even if the trees are damaged aboveground, the root system is likely to survive well enough to produce new saplings. This got researchers wondering if trees that sprouted after a fire were any different from the ones before it. So they looked at a stand of aspens that was part of a controlled burn.