From the files of Donald R. Kirk:
Part 2. All the Same Tree?
Too lazy to count the trees in ‘our’ grove, I estimate there are at least a hundred aspen in this group. Like their close relative, the cottonwood, aspen produce both male and female trees. This results in entire forests of aspen composed of either female or male trees. In early spring aspen bear 1–3 inch long, drooping catkins containing male or female flowers.
An average size tree may yield 1.5 million or more seeds! Still, reproduction by seeds is very chancy, as the seeds are only viable for a very short time. More often the young trees sprout as suckers from a single root system. This gives rise to an astonishing number of trees that are basically all the same tree, clones of the founding aspen tree.
The 100 plus trees in this grove are almost certainly one tree genetically, connected to a single root system. Biologists call such a grove a clonal colony. While the group of aspen here may seem sizable to be all the same tree, it is tiny compared to an aspen clonal colony in the mountains of Utah that covers 107 acres with an estimated 47,000 trees. The 47,000 shoots are all genetically identical, and the Utah grove is sometimes viewed as the world’s largest known organism.
While it is possible to determine the age of the trees in this clone, figuring out the age of the clonal root system is another matter. The vast root system could be tens of thousands of years old.
We wander through this beautiful stand of aspen, trying to avoid treading on the buttercups. We find a single tree that is larger than the others. With no way to prove it, we nevertheless decide it must be the “mother” tree, a seedling that managed to survive and produce the entire grove. We find something else nearby: a tree marked with an ancient arborglyph, a tree carving, that was cut into the soft bark over a hundred years ago...to be continued.