Quaking aspens naturally have the ability to sprout profusely from their root systems to produce a new forest, especially when the main tree is weakened, dies or is removed. This is good for aspen, giving it the ability to reproduce and populate an area quickly after a disturbance such as a fire or avalanche. It is not so convenient for homeowners growing aspens in a cultivated landscape, since the trees shoot out multiple sprouts when cut down or even when left undisturbed.

            

When cutting down a quaking aspen tree, it is necessary to kill the entire root system connected with the original tree. As long as the root system is alive, it will continue sending up sprouts. After cutting down a large aspen in the yard, it may take up to two years of cutting and treating sprouts to completely remove them. Consider these tips:
            

* The herbicide Brush-B-Gone (not Weed-B-Gone) or an equivalent with the chemical triclopyr is well suited for this task and is available at most garden centers. This works best on a freshly-cut stump. If the stump has not been recently cut, it will be necessary to re-cut it, or at least the portion near the bark, to reopen the vascular tissue. Then spray the herbicide on the cut tissue. Glyphosate (Roundup or an equivalent) will also work for treating cut surfaces.

            

* Cut down each sprout you find and spray herbicide on the freshly cut surface. Be careful to limit overspray since this herbicide will kill or injure other things it contacts. Try to remove all sprouts, even in neighboring yards, since the sprouts are no respecters of property lines. Get your neighbors’ permission of course, and make sure you aren’t treating something unconnected.

            

* You will likely continue to have sprouts for sometime, and you should treat them as soon as you see them. It is best to cut and treat them before they have much time to grow.

This herbicide treatment also works for other species that send up sprouts from their root systems, including white poplar.

            

* If you are trying to remove sprouts but not the parent tree, using herbicides is risky. Though it is unlikely that you could kill a large tree by treating several of the sprouts connected to its root system, you will likely weaken it. Instead, consider digging up sprouts and the nearby attached roots if you are trying to save the parent tree.