Knowledgebase
Help in identifying this plant and getting rid of it. #765238
Asked August 02, 2021, 1:30 PM EDT
Dakota County Minnesota
Expert Response
Thanks for the question.
You are correct! It is a willow. Drilling down to the exact species is more difficult. I have narrowed it down to two possibilities: Black Willow (Salix nigra) or a type or Weeping Willow. Here is some information about each:
https://www.minnesotawildflowers.info/tree/black-willow
https://www.dnr.state.mn.us/trees/black-willow.html
https://trees.umn.edu/black-willow-salix-nigra
https://www.gardenguides.com/124856-identify-willow-trees-minnesota.html
https://www.arboretum.umn.edu/willowcollection.aspx
Completely removing this tree will present you with a challenge. As long as its roots remain in the ground, it will continue to send up suckers. As you have discovered the root system is expansive. You will need to use a herbicide containing either glyphosate or Triclopyr. These are systemic herbicides that enter the plant’s duct system and are carried throughout the plant. This will ultimately kill the root system though it may take some time. Cut down all the willows to about 6 inches above ground. Then using a small brush or a paint dauber, apply the herbicide to the cut ends of the willow stems. Be extremely careful about spilling the herbicide on other plants. Within two to tree weeks, the willow root system will be greatly compromised. To ensure this, repeat the herbicide treatment after about two weeks of the first application.
Good Luck!!
Thanks for your response.
My suggestions would apply to any type of willow. Using herbicide on the willows by the storm drain should not lead to any issues, especially if you use a small brush or dauber as I suggested. While you could contact the city, I suspect that they will not be interested. However, do not use any herbicides in swamp areas as there are very strict regulations against doing that. Vinegar based herbicides are typically less effective than herbicides containing glyphosate. In your particular situation I don’t know which one would best meet your needs. Perhaps you should experiment with both and base your final decision on what you observe? Here is an article that compares and contrasts both types of herbicides:
https://fairfield.osu.edu/news/vinegar-it-“safer”-herbicide
Good Luck.