Answer: Aspens like to propagate by sending out shoots in nearby soil where nutrients, good aeration and water are available. Unfortunately a nearby lawn is ideal. There's not a lot to be done except to continue to mow or hand clip the suckers as they appear. Because the suckers are attached to the main root system, any applied herbicide can damage the parent tree. As a last resort, you can remove the original aspens. The suckers will still emerge from the remaining roots but you can treat these with herbicide. Make sure to carefully paint it on the sucker leaves so as to not damage your grass. If you are consistent, eventually the roots will starve and die.
Q&A Library Searching Tips