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Question from Alex -

There are root like structures coming out of the ground in my yard. Do you know if they are normal or if they need treatment? They are making the lawn look weird. There is a large aspen tree nearby. Thanks a lot!

Alex

Answer from Dr. Mike Kuhns, USU Extension Forester and Professor -

Alex,

As you know, aspens put out sprouts along their roots that have a stem above ground and roots below. The resulting plant is clonally produced, so it is genetically identical to the original plant. Regular mowing will keep these sprouts from growing and forming new trees. However, stems will try to form at certain spots along the roots, and will attempt to grow over and over, forming a zone of disorganized growth at the soil surface that becomes woody and that gets larger over time. You can get them out by pushing a sharp spade into the ground all the way around the growth and then cut any final roots that are going down by using the spade as a lever.

Aspen root sprout

Unfortunately, though this will remove the selected woody growths, the cutting of the roots will actually encourage additional sprouting along the roots that are cut. It actually causes the creation of separate trees, each of which will sprout. You can reduce the sprouting by using triclopyr herbicide (i.e. Ortho Brush-B-Gone or similar) or glyphosate (e.g. Roundup or similar). To avoid killing the grass near the growth, you should use a paint brush instead of spraying, applying the herbicide to all of the cut surfaces while they are still fresh (within hours is best for uptake). Doing this only makes sense though if you intend to remove the parent tree, since if you are careful to treat every cut surface there is a good chance that you will greatly weaken the parent tree. That is what I recommend doing, since the sprouts will keep on coming as long as that tree is alive. If you remove the tree you should also treat the stump with triclopyr right away. Also, though treating the stump and cut roots will weaken the remaining roots, you will need to go around your yard and your neighbors’ properties and cut any sprouts that have been left to grow and treat those stems. You need to do this quickly whenever a sprout forms. If you let one grow and get leaves on it, you will have the process starting all over again.

Good luck.