Most of what I know about Quaking Aspens came from parenting a teenager. That's when I mastered the art of choosing my battles and searching for common ground.
Aspens are rebellious, too. They sucker and rapidly reproduce. And, if you didn't want that to happen, you shouldn't have planted an Aspen in the first place.
Teenagers are happiest hanging out in a big group and the same goes for Aspens. You can fight it, to no avail. Or, work this to your advantage. Plant Aspens where they can create a small, shady grove. Eliminate all but a few choice saplings, each year. Aspens are fast-growing but short-lived. By staggering the age of the new, young saplings you're assured of healthy shade trees for as long as you own your property.
Avoid watering and fertilization in early fall. This stimulates plant activity at a time when trees should be slowing down and toughening up their wood for the coming winter.
Give trees a good soaking in late October,after leaves have fallen, before ground freezes.
Should you grow Aspens in your yard? Only if you have room to let them spread. I love the fact that one little Aspen tree can create a whole forest.* In my yard, I've lured the Aspens to send out long suckers to another area, where they are establishing a new grove of shade trees, naturally.
Autumn is a second spring when every leaf is a flower.
— Albert Camus
* Family Affair: Pando is a clonal colony of Quaking Aspen in Utah - a single living organism, with one underground root system that is considered to be the oldest known living being in existence, 80,000 years. Pando covers 107 acres, with 47,000 trunks, which continually die and renew with young Aspens, via the suckering root.
** Populus tremuloides - Quaking (or Trembling) Aspen is a popular tree in high altitudes. Golden yellow leaves in Autumn rattle on the branches, hence the nickname 'Trembling.'
*** These photos are not of Pando.